Ask Slashdot: Surge Protection For International Travel?

New submitter gaiageek writes: As someone who has lost a laptop power supply (and thus use of the laptop) due to a late-night power surge while traveling in a developing country, I'm acutely aware of the need for surge protection when traveling abroad. While practically all laptop and phone power adapters these days are voltage auto-sensing 100V-240V compatible, most so-called "travel" surge protectors are restricted to either 110V or 220V. Given the space and weight constraints of carry-on only travel, I'd like to avoid having to carry two separate surge protectors knowing I may go from Central America (110V) to Southeast Asia (220V). Strangely, laptop specific surge protectors typically are 100V-240V compatible, but this doesn't provide protection for a phone or tablet that requires the original power supply (can't be charged from a notebook USB port).

Is there really no solution out there short using a 110V-240V notebook surge protector with an adapter to go from a "cloverleaf" notebook plug to a 5-15R (standard US) plug receptacle?

Comments

Surge protectors *must* be voltage specific

[markus_baertschi]

The problem is, 200 Volts on a 110V circuit is a surge and will fry a 110V power supply. So surge protectors need to be voltage specific or they become ineffective at lower voltages.

I would go another route: Make sure that your have spare/alternative ways to power or charge your equipment. For example carry a 12V charger for your laptop (also works on some airplanes). Only buy equipment (phones/tablets) you can charge from an USB outlet. Carry a spare USB charger.

This will get easier over time with the USB type C connector and USB power delivery, as modern devices get equipped with it.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

Technically the surge protector could adapt to the normal voltage. Also, technically you should be fine if you use a 240V surge protector on a 110V circuit, as long as the device can handle 240V, so pack a 240V surge adapter and a wide range power supply.

Re:Surge protectors *must* be voltage specific

[BenFranske]

Yes, it's true that 200 volts on a 110/120v circuit might damage a 110/120v power supply. However, the OP mentions that their power supplies are universal 110~240v. That means the supplies can actually handle up to 240v so they only need surge protection above 240v regardless.

Re:Surge protectors *must* be voltage specific

[gaiageek]

OP here. If surge protectors must be voltage specific, that doesn't explain how the laptop-specific surge protectors can be 100V-240V compatible.

As for carrying a spare laptop power supply, that would be just as much weight/bulk as a 2nd surge protector, so kind of defeats the point.

Re:Surge protectors *must* be voltage specific

[Z00L00K]

A surge protector for 230-240 volts is what's needed.

So get a power strip with surge protection for Schuko (Common style in most of Europe) connectors, replace the plug with a male connector same as power supplies as stationary computers have and then get a country specific power cable in the country visited.

The reason to use the Shuko connector is that most devices are available in European format alternative, fewer in the UK format and the Schuko plug is smaller than the UK plugs as well. Any talk about need to identify live and neutral is just bollocks on anything manufactured after 1980.

If all the power supplies connected are auto-ranging up to 240 volts there's no need to have a voltage specific surge protector, the power supplies can cope with it.

Re:Surge protectors *must* be voltage specific

[Z00L00K]

Most power supplies are auto-range or wide range 100-250V or so, so only a surge protector for the upper voltage is needed.

Re:Surge protectors *must* be voltage specific

[David_Hart]

The problem is, 200 Volts on a 110V circuit is a surge and will fry a 110V power supply. So surge protectors need to be voltage specific or they become ineffective at lower voltages.

I would go another route: Make sure that your have spare/alternative ways to power or charge your equipment. For example carry a 12V charger for your laptop (also works on some airplanes). Only buy equipment (phones/tablets) you can charge from an USB outlet. Carry a spare USB charger.

This will get easier over time with the USB type C connector and USB power delivery, as modern devices get equipped with it.

This...

Buy one or several power banks for your phone/tablet. Charge the power bank, not the device, and use the power bank to charge your portable devices.

I use a Kensington K33117 International All-in-One Travel Plug Adapter plus a Monster MP OTG400 BK Outlets To Go Power Strip when traveling. The Kensington travel adapter has a built-in ceramic slow transition fuse rated at 250v 2.5A plus a spare in the removable end. While it will take a grounded plug (i.e. the power strip, it's a tight fit but it does fit) it's not connected to anything, It's not a problem because none of my travel device plugs have grounded plugs, they are all two-prong.

I've never had the fuse blow nor experienced any problem with my devices during travel, so take the above with a grain of salt. Basically, I can't say how good the fuse is because I've never needed it.

This got me curious about how much power I am using for my devices as they have been upgraded since I got the travel plug adapter. Looking at my devices, the Surface Pro 4 tablet takes 1A input (~1.35A for a laptop), dual port 5V 2.1A USB adapter takes 0.5A input, and universal camera battery charger takes 0.2A input. So, a total of 1.7A when I travel for vacation and 2.05A when I travel for business @ 110v. If you are on 220V, the auto-switching power supply will use approximately half of the rated Amps. So, for me, a rating of 2.5A is fine.

Re:Surge protectors *must* be voltage specific

[gweihir]

Indeed. Even when you have a 100-240V device connected to 110V, you must use an 110V surge protector. The problem is that while a 220V surge protector would clamp at a voltage the device can survive, it can only survive reliably if it has been running at 220V because of the way these devices are designed. They have a rectifier and filter capacitor. If the filter capacitor gets charged up from 110V by a surge clamped for 220V (which clamps at around 400...500V), the inrush-current will likely blow the last-ditch fuse in the device and may well damage other components.

So, sorry, what you want is not possible. You must get both.

Re:Surge protectors *must* be voltage specific

[gweihir]

No. Because of the way surges, surge-protectors work and wide-range PSUs work, this is not true at all.

Re:Surge protectors *must* be voltage specific

[Teun]

It looks like you haven't seen a notebook in many years :)

Because it must have been in the days of the 286/386 that the build-in mains power supply was replaced by an external one, also referred to as a 'brick'.

All those I have ever seen are auto negotiating between ~100 - 250 Volts 50 - 60 Hz.

This means they will handle Voltage variations within that range which is not quite the same as handling frequency spikes and surges.

Re:Surge protectors *must* be voltage specific

[gweihir]

If you have a 100-240V "compatible" surge protector, then you have been cheated, as that is not possible to do reliably without significantly more effort than goes into these devices. These will always only offer limited protection at 110V.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

OP here. If surge protectors must be voltage specific, that doesn't explain how the laptop-specific surge protectors can be 100V-240V compatible.

Surge protectors have a clamping circuit, like a MOV, thermal fuses and what not

      https://en.wikipedia.org/wiki/...

These are ALL VOLTAGE SPECIFIC.

Your "laptop specific" surge suppressor is nothing more than a 240V surge suppressor. Modern power supplies (the ones that "auto switch between voltages") have a high-voltage switch to regular voltage on the low side. This high voltage switch is limited to some voltage (most likely around 500V). The purpose of the surge suppressor is to prevent spikes above this voltage.

They call it "device specific" because if you plug in some device that will die at 200V, it will not be protected by that surge suppressor.

Hope that clear up the issue. Just get a 240V surge suppressor and be happy. You can plug it into a 120V circuit without issues.

Re: Surge protectors *must* be voltage specific

[Anonymous Coward]

The inrush current doesn't blow the fuse when you go directly from 0V to 230V by plugging it in. The slew rate is limited by an inductor, and the sharper the spike the harsher the limiting.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

Multi-range PSUs, as in ones without a physical switch, simply have a combination of inductors and capacitors with a bridge diode to create a filtered DC source that can be regulated to the voltage actually needed. The filter and bridge diode need to be rated for the maximum voltage, so a surge from 120 to 240 will still be within the rating of the front end and be on par with plugging the thing in the first place.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

You seem to be quite wrong, making it less obvious by just being vague about "the way these devices are design." In rush current on something the size of a phone charger or laptop power supply is quite small in the worst case scenario, and limiting that rush has less to do with protecting the PSU and more to do with not tripping crappy breakers if you plug them in coincident with the peak of the mains sine wave. You might get a surge of a lot of current, but the total energy actually moved around is not enough to do thermal damage. I've had to deal with enough power supplies for esoteric equipment that had no inrush limits, and the problems amounted to annoyances for smaller ones. Now kilowatt+ plus supplies on the other hand with heavy filtering, or old school power supplies that used transformers instead of switching power supplies (which would be much, much less likely to be setup for multiple voltages without some sort of switch), those can pull enough in rush current to cause more serious problems on both ends.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

What kills PSUs by far is overvoltage, not overcurrent. Even cheap switching mode power supply controllers have over current detection that will shut off the switching element when current limit is exceeded.

Re:Surge protectors *must* be voltage specific

[feenberg]

Aren't nearly all surge protectors made with 330 volt MOVs? Wikipedia has an article on surge protecters which includes this "A lower clamping voltage indicates better protection, but can sometimes result in a shorter life expectancy for the overall protective system. The lowest three levels of protection defined in the UL rating are 330 V, 400 V and 500 V. The standard let-through voltage for 120 V AC devices is 330 volts."

Re: Surge protectors *must* be voltage specific

[adolf]

To a modern, global, switch-mode PSU (laptop power brick), everything (including the nasty non-at-all sinewave that serves as "AC power" in many locations) looks like noise/transient voltage.

They don't care. It's all the same.

Re:Surge protectors *must* be voltage specific

[gweihir]

We are talking surges here, not regular switch on. A typical surge-test uses 500...15000V. A "surge" from 110V to 240V does not even register even in most 110V equipment.

Re:Surge protectors *must* be voltage specific

[mjwx]

A surge protector for 230-240 volts is what's needed.

Actually what is needed is a voltage converter/step down transformer, surge protectors don't downvolt 220-240v to 110v.

Or the US could just admit that 110v is a bad idea and follow the world onto 220-240v.

However for laptops, it usually doesn't matter as most manufacturers make one auto-switching power supply for the entire world. Check your power brick to see if it supports up to 240v, it should say something like "AC 100-240v". As for the rest of your stuff, just make sure whatever you get a step down converter/transformer, then just bring a powerboard/powerstrip from home.

As an Australian (240v), I only have to worry about getting a plug adapter. Most Europeans are in the same boat.

Re:Surge protectors *must* be voltage specific

[geoskd]

limiting that rush has less to do with protecting the PSU and more to do with not tripping crappy breakers if you plug them in coincident with the peak of the mains sine wave.

This has not been true since breakers were introduced. One of the principle advantages to the breakers was a magnetic *and* thermal capability. This allows breakers ( even crappy ones ) to handle inrush of massive machinery.

If you are feeling brave, you can try the following experiment ( I already have with several different types of breakers ): Take a dead short (Large gauge wire like 8 AWG or 6 AWG. Hook it up to a power transistor controlled by a microprocessor. International Rectifier makes some 100A jobbers that can handle spikes of up to thousands of Amps for less than 10ms bursts. Set up a zero cross detect on your microprocessor and turn the juice on through the dead short for 1 full wave of 120VAC. Hook up an o-scope to your mains and check the line voltage as you turn this critter on.

What you will get is one full cycle of severely browned out mains (might drop as far as 10Vp-p. across a 1mOhm load ). For those astute at math, that would be 10,000Amps at 10Vp-p, or about 60 kWatts RMS. As long as you only do this for one full cycle and no more, you will neither blow the breaker, nor significantly heat any of you components. The reason for this is because breakers are mechanical devices and have a specified amount of time before they can "react" to overload. Even their thermal shutdown takes time. Long story short, a standard 15A wall breaker can dispense about 15kAmps for 10ms without tripping. That is far more than the transformer at the pole can handle, and its own internal resistance becomes the current limiting factor. A good line supply will provide you with about 10kAmps before the current limiting drops the line voltage significantly. A typical residential supply will only dump about 1000 Amps before significant drops in voltage. Either way, the breakers will not trip no matter what you do, as long as the entire incident is shorter than 10ms.

This design is very much on purpose. As I have seen, and what these experiments demonstrates is that in-wall wiring, breakers, and utility company equipment are not seriously threatened by short power spikes, so they have no reason to try to protect against them. The breakers in your house are there to prevent enough power from flowing through the wires in the walls to cause them to start fires.

The inrush can however severely damage switching power supplies. Many of them are built to just barely handle the voltages they are designed for. This is done to save money and weight in the extremely competitive mobile power supply market. This market is so competitive, and the margins are so thin, that they will do almost anything sketchy they can to shave pennies off the design. I have personally seen transformerless designs that were built assuming one of the two main lugs was neutral. If they are plugged into a reverse polarity outlet, they short the hot line to the ground directly... This is a common design used on many different power supplies, and is one of the primary reasons you should never open one of those supplies while it is powered. Even in the lab the damn things are dangerous.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

Which is completely irrelevant to your previous statement that a 240 V protection would not work for a 120/240 V device. A surge of 500-15000 V would still be clamped to range of a couple hundred volts, and anything that is slightly over 240 V would have to dump enough energy to lift the caps above their rated volt. That would actually be harder for a device running at 110 which is rated up to 240 V.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

This has not been true since breakers were introduced. One of the principle advantages to the breakers was a magnetic *and* thermal capability. This allows breakers ( even crappy ones ) to handle inrush of massive machinery.

There is a reason it was qualified with "crappy", as what you say is true of many breakers, but not all. I've seen installed household breakers that struggle with start current from vacuum cleaners and large power supplies. And those are not the only kind of breaker that one has to expect when making a consumer product, as there are also breakers in many power strips and other places which are far more cheap in their construction. I've even seen ground fault systems that trip from inrush current, which should be something simple to implement but somehow ones exist that can't handle noise and surges on the lines they monitor (resulting in a lot of wasted time debugging of a device once trying to track down a transient ground fault that wasn't there).

The inrush can however severely damage switching power supplies. Many of them are built to just barely handle the voltages they are designed for.

Yes, they are very sensitive to voltages, especially the cheaper ones. But it is very difficult to get inrush current to cause voltage problems in most topologies, especially when it is inrush to fill a capacitor in some power supply.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

Ding Ding Ding Correct!

But when MOV's get hit with surges they break down. The temptation is to use 'light' movs with lower lifetime joule protect.
So the modern specs look impressive, unless you know they only work a few times

If you can lay your hands on old 1980 ceramic body gas discharge arresters where high voltage makes the normally inert gas conduct. Many old servers and or mainframes or telephone exchanges including DEC were well made. Old TV's used to have inrush transformers, by all means used one of these. In short small and light = limited. Old analogue telephones had these gas arresters - they were dropped as too expensive.

Newer, more modern is not necessarily better.

Re:Surge protectors *must* be voltage specific

[gweihir]

Obviously you do not have the EE understanding required. A 220V surge protector is typically designed to clamp at around 500V. From rectified 110V AC that gives you a 350V relative spike into the capacitors. From rectified 220V it is only 190V. A 110V surge protector is typically designed to clamp at around 330V. That is an 180V spike. If you cannot see that a 350V spike may be a bit more destructive than an 190V/180V one, and that in particular, the components in the device may only be dimensioned for a 200V spike or so as that is what to expect with surge protection done correctly, then you have no business being in this discussion. If you have to ask where these numbers come from, the same applies.

Incidentally, this is only one of the problems with a wrongly dimensioned surge protector. And yes, the surge voltage is relevant, as it influences dU/dt and the surge current. In actual fact, there is a surge model behind this and the surge voltage is only one factor. Also, surge protection devices do not do a perfect clamping, and have maximum ratings. If they are exceeded, the surge protector may short out, fail or even start to burn if not fitted with a thermal fuse. Incidentally, there is a maximum of surges a surge protector can clamp, depending on the surges and its ratings. After that, it needs replacement.

Why do incompetent morons always feel they are qualified to comment on advanced engineering they really do not understand? The Dunning-Kruger effect is strong on Slashdot.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

I mostly ignore AC's. There are too many self-important cretins hiding behind it. Slashdot offers pseudonymity. Use it.

Slashdot offers anonymity. I'll use that. Being ignored by you really doesn't affect my decision.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

And why is 115 a "bad idea"?

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

A 220V surge protector is typically designed to clamp at around 500V. From rectified 110V AC that gives you a 350V relative spike into the capacitors. From rectified 220V it is only 190V. A 110V surge protector is typically designed to clamp at around 330V. That is an 180V spike.

You can't generalize to specific numbers like that, as the protections offered by surge suppression is not a simple clamp voltage. It depends on the voltage, current, and timing characteristics of the surge. The UL1449 for example uses a very specific waveform (which is why they don't like the wording 'clamp voltage'), and that waveform current characteristics from the 2nd edition to 3rd edition. This resulted in a change in maximum voltage measured under their test, so they chose a different wording for the voltage protection in the 3rd edition to make sure which of the two ratings results is referred to. There is no requirement that a particular service voltage be at a particular protection voltage, and you can find both 110 and 220 at the 400 V rating, which is more than good enough for most consumer products. Most commercial environment type 3 suppressors have 500-700 V VPR in my experience, where you don't see any difference between 240 and 120 V devices (other than some 240 V ones will have a 100V difference L-L vs. L-N rating). These numbers still end up being a guideline, as the actual voltage during the test is rounded up in categories, and for a type 3 test like most power strips with protection, it assumes you are 10 m from the distribution box.

the components in the device may only be dimensioned for a 200V spike or so as that is what to expect with surge protection done correctly,

If any provisions were made for surges, it would have been done at maximum running voltage, and the components will have a maximum voltage rating. If the device can handle the a surge operating at 240, then it can handle the same surge operating at 110. Look at the front end of any common power supply, and you will find a combination of capacitors, inductors, a bridge rectifier, and maybe a transformer for dealing with common mode noise. None of these care if you have a voltage jump from 110 to 500 vs 240 to 500, only what the final peak voltage is. With the amount of stuff passive there, even just wiring for a type 3 situation, the dV/dt is not even close to an issue by the time you get to any of the actual switching equipment, and the total energy is not enough to cause thermal problems in the wiring (heck, the 50 mC charge in the UL waveform has trouble overvoltaging a filtered supply without a suppressor once you get above a couple hundred watts). The very front end of the filtering is usually 630 V components for 120/240 power supplies (and those components can handle higher voltages for short periods yet, with caps varying from 10-60% surge voltage ratings), which is why you find so much commercial suppressors with ~600 V VPR.

If they are exceeded, the surge protector may short out, fail or even start to burn if not fitted with a thermal fuse.

This is true of any suppressor regardless of what voltage your device is running at. Cheap suppressors won't help if you are in a country where the voltage may drift 30 or more volts out of spec.

Why do incompetent morons always feel they are qualified to comment on advanced engineering they really do not understand? The Dunning-Kruger effect is strong on Slashdot.

I ask the same thing, especially for those that seem to post stupid mistakes over and over again, or try to assume that advanced engineering amounts to just a couple numbers worked out on a napkin. After all, maybe no one will noticed because there couldn't possibly be someone who's had to build and test power supplies for use in extreme environments, and spend a lot of time tracking down what actually fails and what doesn't, what off-the-shelf parts are capable of vs. what the specs claim, etc...

Re:Surge protectors *must* be voltage specific

[xtronics]

Not really - anyway - most of these 'surge protectors' are simple MOV blocks that get blown open after a few years of use. (They silently die in the line of duty).

Amazing how many people here don't know anything about transients. - Common mode vs differential mode etc.

Most power supplies have one built in - and work well above both voltages.

The key bit is most transients are at RF frequencies - you don't have to know down all of what gets on the first cap past the rectification - and with PFC the inductor will just reflect most of it.

Much more important is what happens when your computer is hooked up to two different grounds (Ethernet vs power mains ) and it becomes a shunt between the two.

Re:Surge protectors *must* be voltage specific

[RockDoctor]

The problem is, 200 Volts on a 110V circuit is a surge and will fry a 110V power supply.

The OP specifically stated that the power supplies under discussion are rated to take 110 or 240 V. This is not an issue.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

Not really - anyway - most of these 'surge protectors' are simple MOV blocks that get blown open after a few years of use.

Not sure if you replied to the right comment or not, as the one you replied to was describing the components in the front end of a SMPS, not a surge suppressor.

The key bit is most transients are at RF frequencies...

Depends on the situation and who you are asking. If travelling overseas, you'll deal with a lot more issues from voltages drifting way out of spec, and there is not much a regular, cheap power strip surge suppressor is going to do about that. That is on a time scale on the far opposite end than RF problems. Places with thunderstorms have to deal with a lot of spikes from lightning strikes some distance away, and that has a characteristic pulse that some testing standards are built around. In household situations, you would need something else going on that is pretty wrong to have RF issues that would kill a power brick, whereas in an industrial setting, you might have high power equipment near by dumping noise that can't be mitigated at the source.

Much more important is what happens when your computer is hooked up to two different grounds (Ethernet vs power mains ) and it becomes a shunt between the two.

Most consumers aren't dealing with shielded ethernet, and that are should be grounding only one end of the shielding. The data lines themselves are isolated.

Re:Surge protectors *must* be voltage specific

[Anonymous Coward]

You missed the point. If the power brick can handle 110-240V then simply let it: there is no need whatsoever to transform 240 to 120. If you have a power brick that will only do 120V, replace it with one that CAN.

Also, nobody uses 110, except for places that are too far from a substation to actually have 120V. If I measured 110V in my house, I'd demand the power company come and fix it, because it's out of spec.

Re:Surge protectors *must* be voltage specific

[arglebargle_xiv]

If you're serious, I would use a rotary converter. Failing that, at least a ferroresonant power conditioner. That should allow you to plug into just about any dodgy power source without worrying about frying things.

Re: Surge protectors *must* be voltage specific

[Teun]

Indeed and it's a good thing, one reason why I have trouble understanding the reason why OP's power supply failed.

Re:Surge protectors *must* be voltage specific

[stoatwblr]

Yes, 200V on a 110V circuit is a surge, but most "typical" surges are 2kV or higher common mode (both lines going high relative to earth) due to lightning strikes.

Sustained higher voltage surges on low voltage lines are normally a result of 11kV distribution lines falling on local feeders. The best you can hope for in such cases is that the fuses do their job before your wiring catches fire.

My experience is that power lines don't get much in the way of surges - there are so many transformers along the way that ground point are plentiful.

Comms lines are another matter entirely. In another lifetime (as a telco tech) I used to routinely see smoking wires hanging in mid air where a line card used to be and it's not at all uncommon to find black arc tracks inside modems or phones after a strike.

Most surge arrestors work fine for the first hit, but self destruct whilst doing so and don't block the second and third ones a few hundred milliseconds later. In addition they tend to interfere with line characteristics and cheap ones often badly screw up DSL circuits.

For "wrong voltage" on a power circuit (200V on 110V, etc) that's what fuses exist for. Surge arrestors are supposed to clamp short period , high impulse transients.

Re:Surge protectors *must* be voltage specific

[stoatwblr]

> And why is 115 a "bad idea"?

Stupidly high circuit currents for starters, resulting in having to use heavier switchgear and much heavier wiring to avoid excessive circuit losses and heating issues. losing 10V in a 220V circuit isn't an issue, but in a 110V circuit it can take you out of supply tolerance.

The actual domestic feed into a USA house is 220V, not 110V. It's centretapped to provide 2 "pseudo phases". This has resulted in some parts of the world that started on a US system having 220V 60Hz supplies on NEMA sockets (be warned if you're in the Philippines or Thailand)

110/115V was originally used on Edison's DC supplies, because higher than that started having major problems controlling arcing when things were switched off

DC arcs are self sustaining. AC arcs self-quench every half cycle. This is why the same switch will have wildly differing AC/DC current ratings on the rating plate - the AC rating is what can pass through the contacts, whilst the DC one is about how fast and how far apart they open, in order to be able to safely switch whatever's being controlled OFF.

Trivia: Whilst Edison was running around telling people Tesla's AC was dangerous and electrocuting dogs to prove it, 2-3 electricians per month were being killed by the "safe" DC supply system.

Re:Surge protectors *must* be voltage specific

[stoatwblr]

"Also, nobody uses 110"

I point you to parts of South America and certain areas in Japan.

Re:Surge protectors *must* be voltage specific

[stoatwblr]

"I've never had the fuse blow..."

Fuses and circuit breakers are there to protect the wiring and prevent a fire.

They're not there to protect devices.

Re:Surge protectors *must* be voltage specific

[stoatwblr]

MOVs have to be rated higher than the expected sinusoudal _peak_ voltage.

For most mains circuits the allowable RMS deviation is "nominal" RMS -10%+15%, which means that peaks need to be sized appropriately. If the supply isn't clean then the peak might be slightly higher still.

This brings up an important point for a lot of cheap chinese electronics rated for "220V" or "220-240V" - Whilst the supply in the UK is a nominal 220V, my house's _normal_ line voltage is 245VAC and it can go as high as 265VAC whilst still being within allowable power system tolerances (this is applicable across europe, but most of the EU centres on 220V whilst the UK centres on 230V, as do a lot of ex-british colonies)

I've told chinese suppliers that the line voltage here is 245V and the standard response is that "this is out of spec" - when you point out the legally allowable variations in supply voltages(*) you can almost hear their heads exploding. Far too much single-voltage kit is made on the basis of "nominal +-5%" and that's simply not safe.

(*) Most "developed country" mains noise and voltage excursion standards were written in the 1930s, when "electronics" simply wasn't sensitive to any of these kinds of things.

Re:Surge protectors *must* be voltage specific

[gweihir]

I can try to simplify things down so that the morons claiming that a 220V protector is perfectly adequate for a wide-input PSU running at 110V may get some glimmer of understanding that things are more complicated. I am well aware they are _much_ more complicated.

Re:Surge protectors *must* be voltage specific

[geoskd]

I've even seen ground fault systems that trip from inrush current, which should be something simple to implement but somehow ones exist that can't handle noise and surges on the lines they monitor (resulting in a lot of wasted time debugging of a device once trying to track down a transient ground fault that wasn't there).

Ground fault devices that experience even a transient current *must* trip. Any ground fault excursion is dangerous, and the result of a faulty piece of equipment. If you were seeing a transient ground fault, in a device, that device is *dangerous*, and the design fault with that device should be corrected. Most likely, you have some relatively high power signal that is coupling to the case. The easiest way to fix that problem is to ensure a strong enough coupling of all of your power supplies (bigger bypass caps), and better grounding (Most likely culprit is unexpected ground loops, or parts too close to the chassis ground). You might also have been victim of counterfeit breakers, which did not actually meet the CE/UL markings on the devices.

Lindy surge protector with usb

[mriya3]

I have a Lindy Surge Protector (model number 73311) which has a cloverleaf input, a cloverleaf output, a "universal" (Multi region power socket) output plug, and 2 usb outputs (1A maximum). It's rated for 660W max at 110V and 1380W Max at 230V.

Re:Lindy surge protector with usb

[gaiageek]

OP here: thanks for this, as it's at least an interesting variation on my current solution. I was hoping to find something in a more simple cube/outlet format that plugs right into the wall (ideally with retractable plug) but this may be the next best thing.

Re:Lindy surge protector with usb

[thegarbz]

I'm skeptical. Devices like that may work to protect 220V devices from surge but I highly doubt that a 110V device will be covered. Proper surge protection is not something that can handle wide input voltages without subjecting the low voltage to at least the high voltage.

Re:Lindy surge protector with usb

[gweihir]

A fast surge will create a huge inrush current into a device running at 110V when the surge protector is dimensioned for 220V. That has a good change to damage or kill the device. On a slow/weak surge, it will offer reasonable protection.

Original power supply

[ArchieBunker]

What the hell are you talking about? Buy several dollar store USB chargers. If one burns up throw it away and use one of the spares. Maybe you want to lug around a Tripp Lite power conditioner with you?

Re:Original power supply

[Anonymous Coward]

It's well documented that many of the cheap USB chargers don't put out the same waveform quality as the more expensive ones. They're manufactured cheaply and, in many cases, you get what you pay for. At best, the if the waveform quality being output is poor, you'll end up with a device that charges slowly. But some of the cheap chargers can actually damage the devices or possibly be fire hazards. You get what you pay for when you go cheap. I'd strongly recommend against this advice.

Re:Original power supply

[Anonymous Coward]

I hope you realize that the optimal "waveform" from a USB charger is a flat line. There isn't such a thing as "waveform quality" with DC power, which is what USB uses. Ripple, maybe, from insufficient filtering, but not "waveform". That is only an issue with inverters that output AC mains voltage power.

Re:Original power supply

[Anonymous Coward]

Same AC here. On that, you're right, my mistake. I posted in good faith and screwed that up, I apologize. That would be the correct terminology for a power inverter, and I was thinking of that when I posted my comment, which of course takes DC and outputs AC. However, I stand by the basic claim that cheap USB chargers may result in slow charging, could damage hardware, and even be dangerous. You're right that they are supposed to maintain a constant voltage. Apple's charging brick has been tore down and the basic conclusion was that they went above and beyond what was necessary for safe and fast charging. Other name brand chargers aren't quite that expensive but are probably good enough. Some of the cheap ones, though, are a problem. I don't expect to find a quality charger at a dollar store. And yes, it should maintain a flat line, and cheap USB chargers are much more likely to produce voltage fluctuations.

Here's a link showing the components in Apple's charger: http://gizmodo.com/5911904/why-apples-iphone-charger-is-so-expensive. And they note that it's well filtered to maintain a constant voltage and not produce spikes and dips.

Re:Original power supply

[Anonymous Coward]

what waveform 5 volts dc you fucktard

Re:Original power supply

[gweihir]

Most clueless posting so far, USB power is DC, no "waveform" present. The actual problem is that they are often too weak and can heat up dangerously.

Re:Original power supply

[Anonymous Coward]

I always bring my own massive hand-wound 50/60Hz transformer with me as carry-on baggage.

That thing works like a CHARM.

Re:Original power supply

[Rising Ape]

Not sure about you, but I'm not entirely comfortable plugging something that cost $1 into the mains.

Re:Original power supply

[Chrontius]

http://www.righto.com/2012/10/...

Except some of them do produce a waveform where a line should be, and it's good to know which ones - you don't want to run that into a cell phone you like.

Re:Original power supply

[Anonymous Coward]

If it's not my mains and I can get my stuff out quickly and safely then I'm not worried.

Re:Original power supply

[Anonymous Coward]

Nice to see you bothered to read posts that were posted 2 hours before yours.

by Anonymous Coward on Sunday February 07, 2016 @10:39AM (#51457111)

Same AC here. On that, you're right, my mistake. I posted in good faith and screwed that up, I apologize. That would be the correct terminology for a power inverter, and I was thinking of that when I posted my comment, which of course takes DC and outputs AC. However, I stand by the basic claim that cheap USB chargers may result in slow charging, could damage hardware, and even be dangerous. You're right that they are supposed to maintain a constant voltage. Apple's charging brick has been tore down and the basic conclusion was that they went above and beyond what was necessary for safe and fast charging. Other name brand chargers aren't quite that expensive but are probably good enough. Some of the cheap ones, though, are a problem. I don't expect to find a quality charger at a dollar store. And yes, it should maintain a flat line, and cheap USB chargers are much more likely to produce voltage fluctuations.

Here's a link showing the components in Apple's charger: http://gizmodo.com/5911904/why-apples-iphone-charger-is-so-expensive. And they note that it's well filtered to maintain a constant voltage and not produce spikes and dips.

and

by Anonymous Coward on Sunday February 07, 2016 @11:18AM (#51457315)

Yes, how dare I make a mistake thinking of power inverters (DC->AC) instead of power supplies (AC->DC) while the basic premise is correct about cheap power supplies, and then apologize profusely for the error. I'm glad to know you've never made a mistake before. A proud day for you and your family, AC.

Oh, wait, you didn't. What was that about clueless posting?

220V should be sufficient

[bosef1]

So I'm clear: you have a collection of devices with switch-mode power supplies that can handle the global 100-240V power, and you want a surge suppressor that will protect you on any voltage.

Since your power supplies can handle up to 240V, you just need a surge suppressor that handles spikes above 240V. So buy a 240V-rated surge suppressor, and use a 120V plug adapter for countries with lower voltage. Since your devices already handle up to 240V, then they can handle minor over-voltages on 120V systems just fine. Bigger spikes, like lightning, are going to be high over-voltages regardless of the base voltage.

I'm not sure of your solution if you have devices that have only-120V or only-240V power supplies, and you need a surge suppressor that can protect both. Buy new wide-band power supplies or build your own (it's not that hard).

Re:220V should be sufficient

[Anonymous Coward]

Yes, but no...

The kind of spikes that you get in developed countries will be absorbed by a cheap 220V surge protector (typically a dime size 240V zinc-oxide MOV), but the kind of prolonged over voltages that you can get from a bushwack diesel generator will still fry your kit.

So, pretty much the only real solution is to take a spare PSU or two with you and make sure that the generator is running and has a steady load (for example a bunch of lights) on it before you plug your kit in and take your laptop PSU out before you turn the lights or the generator off.

Re:220V should be sufficient

[Anonymous Coward]

All the OP needs to do us buy a basic local surge protector for < $10. There is no need for a "global" option. If you can afford to bounce around all over the world, you can buy a cheap protector from any local consumer electronic shop, or just ask the hotel to provide one.

The OP is really an advert in disguise. There will be a highly promoted product with the hour.

Re:220V should be sufficient

[MightyMartian]

This is the new more moral Slashdot. They'll wait at least three hours!

Re:220V should be sufficient

[gaiageek]

OP here. I appreciate your theory, but sorry, this isn't an advertisement in disguise - and if you believe one can arrive in a developing country and just buy a surge protector within the hour, I would guess you haven't been to the kind of countries I'm talking about (or arrived at 3am when local shops are all closed). When my Thinkpad power supply got fried in India (as mentioned in the OP) I literally spent weeks trying to find a replacement: I'd call a local shop, they'd say they ordered it and it would arrive in 2 days and they'd call me. 4 days later I'd call and they'd say it would be there in 2 days and they'd call me. (They never called). I'd change towns and go through a repeat of the same situation. I finally gave up trying.

Keep in mind as well: not wanting to waste time searching for a new surge protector every time I switch to a different region; wanting to use a quality surge protector from a brand I know is reliable, and not a cheap one as you suggest.

Re:220V should be sufficient

[Z00L00K]

Power strips with surge protectors worth their price aren't $10, they are closer to $100 in Europe.

For $10 you may get the cheapest possible ordinary unprotected power strip.

Re:220V should be sufficient

[gaiageek]

OP here. Your assumptions are correct: both power supplies (laptop & USB power adapter) are 100V-240V compatible. Your suggestion to simply use a 240V-rated surge suppressor even when on 110V is one I hadn't considered, and your reasoning seems sound. If anyone has actually tried this with without problem, please post about it.

Re:220V should be sufficient

[jandjmh]

If I had mod points I would mod this up - most sensible post in this thread so far. So called surge suppressors are only useful to minimize the amplitude of very short, very high voltage but low total energy transients of the kind created by lightning (nearby, not a direct his) and other arc like events, such as sparks created by connecting and disconnecting loads.

If you are somewhere third world, and the nominal 220V line goes to 260V and stays there for a while (fractions of a second to many seconds) the kind of surge suppressor found in power strips is useless. Your adapter will probably fry - and with luck fail in a way that blows a fuse inside without sending any damaging over voltage to the device it is powering. Better quality power adapters have added parts on the output that clamp the DC to safe limits even if the upstream parts in the adapter are being overvoltaged to failure.

So use good quality (expensive brand name) adapters and take extras. They may die, but should sacrifice themselves to save the attached gear.

PS - I spent years in industry designing power distribution, regulation and filtering gear for pro audio - including equipment designed for touring sound that had to run from generators that would sometimes put out excess voltage for a relatively long time if too much load was shed suddenly.

Re: 220V should be sufficient

[gaiageek]

OP here. Thanks. Your comments are in line with my experience having the laptop power adapter get fried. As I asked elsewhere, what about using an outlet adapter with a replaceable fuse? Maybe even using lower rated fuses? A stock of 10 extra fuses would be a negligible size/weight addition.

Re:220V should be sufficient

[mjwx]

If you are somewhere third world, and the nominal 220V line goes to 260V and stays there for a while (fractions of a second to many seconds) the kind of surge suppressor found in power strips is useless. Your adapter will probably fry - and with luck fail in a way that blows a fuse inside without sending any damaging over voltage to the device it is powering. Better quality power adapters have added parts on the output that clamp the DC to safe limits even if the upstream parts in the adapter are being overvoltaged to failure.

That being said, I've travelled all over the third world from Colombia to Thailand and I've never had to use a surge protector. Most devices are solid enough to handle dirty power and most hotels, coffee shops and what not will have surge protection installed at the mains if power is that dirty (They dont like replacing all their electronics when the power company screws up).

Surge protectors are just another thing taking up space in my bag... so I dont bother carrying them.

Re: 220V should be sufficient

[gl4ss]

if you manage to find some voltage blown fuses sure but I guess those would be surge protectors.

a regular fuse would I guess work with brown outs to some extent.. (current gets higher as voltage goes down).

voltage dropping to half or about is a more common occurance in these parts of the somewhat developed but really not developed asia anyways...

Three headed outlets and two surge protectors.

[maeka]

It sounds like you are traveling with only passive adapters, and so you would need to protect each and every device separately.

So own two single-outlet surge protectors, for they are quite small and as mentioned elsewhere they must be voltage-specific and make your chain thus:

PassivePlugAdapter:SingleOutletSurge:ThreeHeadedOutlet(s):Appliances

This will pack quite compactly, as the N Passive Plug Adapters get replaced with N/3 Three Headed Outlets

Isolation Transformer

[Anonymous Coward]

What you ideally want is some old school iron 1:1 isolation transformer or a variac that will attenuate the transients. Unfortunately these are so heavy and shipping and cartiing them around in your baggage will probably make it more economic just to buy a spare solid state power supply. Welcome to the future.

-K

Re:Isolation Transformer

[Z00L00K]

You don't lug around a 1:1 transformer if you are traveling around the world. You want to travel relatively light.

I'm confused

[OzPeter]

If you are traveling with a laptop whose power supply is capable of handling either 110v or 240v, why do you care about a surge protector for 110v? Surely all you need is a single surge protector that is rated for the highest voltage that your laptop can handle.

Also I wouldn't be too concerned about the 220v/240v differential. The components used in surge protectors don't suddenly cut off all spikes that just creep over their limit. In fact MOVs limit voltage to 3 to 4 times their rated value. So a 10% difference in line voltage is nothing to them.

Buy on site

[Crowd Computing]

Rather than carry why not buy on the spot in the country you're travelling to? Every airport should have a duty-free shop of some sort. What you'll probably find are power strips with surge protection rather than something specifically marketed as a surge protector. Look for one with a fuse or a mini circuit breaker. If you're worried about the quality, then you can try daisy-chaining two of them.

Re:Buy on site

[gaiageek]

Buying on site isn't an option when you arrive at 3am on an overseas flight.

Re:Buy on site

[ediron2]

Because the Lindy that another poster mentioned is 10 euros. In an airport shop, it'll cost 30-60 euros, and/or be a chinese knockoff with a higher margin. Travel light, not foolishly.

Re:Buy on site

[Anonymous Coward]

Aren't most duty free stores 24 hours?

Given the cost of operating a store in an airport, I would expect most stuff there is 24 hours.

Re:Buy on site

[mjwx]

Rather than carry why not buy on the spot in the country you're travelling to? Every airport should have a duty-free shop of some sort. What you'll probably find are power strips with surge protection rather than something specifically marketed as a surge protector. Look for one with a fuse or a mini circuit breaker. If you're worried about the quality, then you can try daisy-chaining two of them.

Personally I carry one socket adapter and a powerboard.

That way, I can charge all of my devices from one power point. I've also got a powerboard with universal outlets so that I can plug in Australian and local electronics. Useful if the only useful power point is being used by the TV or what not.

However I dont bother with surge protection. I've never had any of my electronics fail on holiday and if the power is regularly that dirty, the hotel will have surge protection installed at the mains as they dont want to replace all their TV's, computers, set top boxes and alarm clocks every time the power surges, let alone get complaints from their guests about dead laptops.

Re:Buy on site

[wvmarle]

Most countries where one would need such a surge protector, I wouldn't trust on having those things available - or if available, being of good quality.

Re:Buy on site

[amyreyna]

Not in every airport can find a duty shop or any shop that sell surge protector, especially if traveling to developing country but not to the capital city.

Here's what I did

[Anonymous Coward]

From US, but spend 90% of my time abroad for work. I bought a US power strip w/ surge protector, for my devices to plug into, and then attach a voltage adapter to the input plug on the strip. I swap adapters depending on what country I'm in--each of which is only slightly larger than the length of the plug on the power strip, so it's not a big deal to carry a half dozen of them around in my luggage. This has served me well for about 3 years now.

Re:Here's what I did

[BenFranske]

You shouldn't do that. The US power strip is likely only rated for 120v. If you use it with an adapter in a country with 240v service you may find that some of the clearances are not enough and you get arcing, thus a fire hazard. I've actually had this happen to me. A better, but similar solution is to get a 220/230/240v power strip with surge protector. You can even get one that will accept US style plugs if you'd like. As long as your power supplies are rated for up to 240v input you'll be protected from surges.

Re:Here's what I did

[burtosis]

You shouldn't do that. The US power strip is likely only rated for 120v. If you use it with an adapter in a country with 240v service you may find that some of the clearances are not enough and you get arcing, thus a fire hazard. I've actually had this happen to me.

The voltage required to start an arc is around a million volts per meter. The 110V difference requires under four thousandths of an inch additional clearance given no insulation at all. If that's the issue I'm going to argue the device was so cheaply made it was already a fire hazard.

A more likely scenario is cheap components (like capacitors for example) and overall bad design.

Re:Here's what I did

[stonefoz]

Arcing is just about impossible. However the fuse and/or circuit breaker is most likely rated for less than 200 volts. Under rated circuit breakers and fuses may not disconnect higher voltages than their rating. OP will likely have no issues until an over current happens. The it will be a gamble of it may safe-fully disconnect or may catch fire. Voltage and Amp ratings are for both normal situations and what happens when things go bad. It may go very bad with wrong ratings.

Re:Here's what I did

[Z00L00K]

Just because it works for you doesn't mean it will work well for someone else with another brand of surge protector. The safety level on the US power strips aren't as good either compared to the Euro variants.

Re:Here's what I did

[Teun]

That's why he has a voltage adapter (AKA a transformer) in the INPUT of the strip :)
Not a bad idea when all your kit is for US voltage. But a transformer that can handle several 100's of Watts is going to be heavy, like my Thinkpad has a 170W power supply.
The advantage is it will to an extend suppress some high frequency spikes by virtue of it's inductance.

Re:Here's what I did

[Anonymous Coward]

Of course, the problem goes both ways. Using a power strip designed for 220V may have thinner gauge wires that may overheat when the current is doubled in 110V environments. Ideally, you'd want a well-engineered strip that has the thicker wires for 110V loads and the clearance and/or insulation for 220V.

If I were facing the OP's problem, I'd consider carrying a spare laptop power brick, making sure everything else can charge off of USB, and perhaps one little mains to USB charging brick just in case the laptop dies or I want to charge a phone without unpacking everything else.

When I lived overseas, I got in the habit of having a proper UPS to act as the surge suppressor and general power conditioner to ride out brownouts etc. Now, back in the US I continue to do so for desktop PCs and network equipment. But, I've never lost a laptop or its power brick even without them...

innovolt

[Anonymous Coward]

I'm not sure what portable solutions from Innovolt are available, but we've had very good results with home devices. We've had numerous lighting strikes near by and the Innovolt device has protected our computer and TV. Other appliances that were not protected have been damaged. Innovolt offers better protection because it is not voltage spikes that do the most damage, but current spikes. Innovolt looks for leading indicators of power problems and actually disable the circuit with a relay. It is far better than simple filters and MOV's.

Mains isolation transformer

[Anonymous Coward]

Mains isolation transformer? Should work with 120 or 240 v but they tend to be bulky.

These work well, and are dual voltage

[Anonymous Coward]

Both pass 220 - If you're using gear made for US, Canadian, or Japanese markets, just grab one of these and a $1-3 plug adapter appropriate for the local market.

http://www.amazon.com/Coocheer-2-outlet-Protector-Smartphone-More-black/dp/B00WMPFNHQ/ref=sr_1_3?s=electronics&ie=UTF8&qid=1454861885&sr=1-3&keywords=Coocheer

http://www.amazon.com/gp/product/B0015DYMVO/ref=pd_lpo_sbs_dp_ss_3?pf_rd_p=1944687502&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B004CLYJ0U&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=065WZ88RECP8QRW6ZS5A

Re:These work well, and are dual voltage

[gaiageek]

OP here. Thanks! I've seen that Belkin one before but didn't know people had used it on 220V despite it only being rated for 110V.

Buy them

[DogDude]

If you can afford to travel to multiple continents, then there's no reason why you can't spend a few bucks and buy the surge protectors you need when you arrive on the continent, and just donate them when you leave.

'surge protection' internationally

[rossdee]

Well don't go to Afghanistan, Iraq, or Syria
all three have experienced a 'surge' of troops from the US, Iran, or Russia

Why not two

[Anonymous Coward]

Just carry two power adapters

Power Rating

[tempmpi]

This sounds like a good idea, however when using a 240V surge protector at 100V you need to consider the reduced power rating. The power rating is likely mostly an maximum current rating and the same amount of power at 100 V instead of 240 V uses 2.4 times the current. So if you need 150 Watt maximum power at 100 V, you should use a 240v surge protector rated at least 360 W.

Re:Power Rating

[Anonymous Coward]

OP asked for a laptop PSU, 150 is more than enough

Not what your asking for due to weight constraints

[Trax3001BBS]

But what you really need is a UPS, It not only prevents surges, it cleans up the voltage outputting a near perfect sine wave.

As mentioned an Isolation Transformer would also do the trick, but again weight constraints prevent their use.

While I wouldn't put much faith in those surge arrestors, trusting a circuit breaker over one. APC has one on Newegg.com (quick search) http://www.newegg.com/Product/... - for cheap but 120 volts.

As one reviewer to the above product put it " So-called surge protectors, IMO, fit into one of the most ethereal realms in I.T. Go ahead and Google, "Do I need a surge protector," and you'll get answers from both sides of the fence--in pages upon pages of search results. That's because the answer is subjective."

Electricity

[Anonymous Coward]

Sure
Take along an electric motor, a variac so you can regulate the rpm of the motor, a generator to hook up to the motor to deliver the voltage required for your power adapter bricks, et voila, instant surge protection, the motor will not spin a lot faster because of a surge, due to inertia, and it is also better able to deal with a simple mains related voltage spike, unless the engine shorts out, but hey, better short out the engine than the power brick for you important and expensive device.

njoy

[wdw]

Re:Electricity

[Teun]

That's what we call a 'Rotating Transformer', with a couple of pulleys and a belt you can even make it change between 50 and 60 Hz frequency.
Just a pity the one I use weighs nearly half a ton.

But as a surge isolator it is bullet proof.

How about a battery pack?

[Alypius]

I don't think this is quite what you're looking for, but my wife and I have used a spare power brick with great success:

Poweradd Pilot Pro 32000mAh External Battery Pack

Much safer than relying on a non-grid electrical supply.

Re:How about a battery pack?

[Anonymous Coward]

"Safer" by your definition, but more batteries are not such a safe option to bring on an airplane.

Any will just do

[d4fseeker]

General plug-in surge protectors just short to ground whenever the component inside triggers over X volt. According to Wikipedia the lowest trigger voltage is 330V for 110V circuits, so even a 110v-rated protector will work fine as the device MUST be able to handle such spikes without damage for certification. However note that especially in developing countries the surge protector may NOT be enough but the adequate solutions are probably far too heavy for you.

Re:Not what your asking for due to weight constrai

[Trax3001BBS]

But what you really need is a UPS,

Putting a bit more thought into this, I can see rigging up an expensive GFI (not a GFCI) -one that trips instantly or faster than normal to do what you need, .

Re:Not what your asking for due to weight constrai

[Anonymous Coward]

Surge protectors work, but only if they're part of a complete overvoltage protection system. Power strip surge protectors are only meant to filter out the remaining surge after a lighting arrestor and a house level surge protector. Induced voltages from lightning strikes easily overwhelm stage 3 surge protectors if they're used by themselves.

You're doing it wrong...

[itsme1234]

Modern good laptop power supplies aren't that easy to kill; probably many mains appliances the locals use are more sensitive to troubles on the line (not only spike but also short drops), from fridges or air-condition units (anything that's compressor-based), washing machines, etc. Sure, PSes can die out of the blue, like mostly everything else but you might not be able to prevent this with a surge protector.

If it is critical to have the laptop available then you need to carry (at least) two power supplies AND TWO LAPTOPS! Frankly the power supply can be replaced almost everywhere for less than the cost of 2-4 beers from minibar, is just a 12-20V DC power supply (it can be also jury-rigged from basic parts - YES I know about the laptops with data pins, etc but still a basic supply will work). In fact it is more likely the laptop will die (not only from electrical problems!).

If you don't really need a backup laptop you can plan to use the phone for most of the communication, basic browsing, etc. You can have a memory stick with the important files, bitlocker encrypted if you want, even a fully encrypted bootable linux distribution if you so desire. Heck, you can borrow a machine if absolutely needed at Everest Base Camp, I'm sure you'll be fine anywhere else.

And why, WHY, WHY, WHY would you have in 2016 a phone "that requires the original power supply (can't be charged from a notebook USB port)" ?!?!?!?!!??! YES, we all knows somebody who still has a Nokia from 2008 with the round connector and a battery that goes for three weeks when new and even now from Monday to Friday without any sweat. But I haven't seen anybody on an intercontinental flight with something like that for a while. Even if I do see somebody I'll just assume it is a second phone, to use with a local SIM...

Re:You're doing it wrong...

[gaiageek]

OP here. My situation isn't critical enough to warrant carrying more than a half-pound of extra gear, which rules out an extra power supply and certainly a 2nd laptop. As you mention, I can always use my phone.

As for a "phone that requires the original power supply" - that was misleading. All my devices (save the laptop) can be charged from from USB, but the laptop USB ports tend put out the standard 500mAh, so it can be a long time charging compared to a 1000mAh USB charger. Also, I have encountered devices (the HP Touchpad) which, if depleted to 0% battery, will not charge without the stock charger. I no longer use a Touchpad, but the experience taught me that "USB charging" isn't so universal and the stock charger may be necessary.

Re:You're doing it wrong...

[Anonymous Coward]

I have traveled a LOT, all over the world, since the days when I had to carry screwdrivers, wire strippers and alligator clips to hook up my 1200 baud modem in hotel rooms.

You don't need a surge protector. More often than not they make things worse rather than better. A well-designed laptop power supply already has all the protections that are reasonable for the space.

You've had bad luck, but it's more likely that the power supply failed spontaneously than that it was really caused by the power surge.

What you need is a spare power supply and MONEY. Money is small and light and can be traded for a new power supply if/when you need one.

If for whatever reason you really can't be without a working laptop even for a few hours late at night (when shops are closed), then you do need some kind of backup - the laptop can die too, you know. Depending on what you're doing a smartphone or tablet with a Bluetooth keyboard might be sufficient.

Good luck.

Re:You're doing it wrong...

[Anonymous Coward]

I live in Northern Mozambique. Voltage fluctuates 60 to 300V. I plug my Apple power supplies (MacBook Pro, USB) straight into the wall and they're fine. I have a computer lab with 17 laptops all plugged straight in since 2009 and we haven't lost a single one to power quality issues.

Since 2005 I've only ever blown a MOV once in a power strip that was plugged into a line struck by lightning.

For travel surge protection isn't worth the weight and hassle. Leave a backup at home and just plug into the outlet wherever you are. Modern switching power supplies, especially OEM equipment purchased in the USA will be fine.

Re:You're doing it wrong...

[adolf]

Questions:

1. How do you know it was a surge that killed your PSU?

2. What else was your laptop plugged into when it got roached?

Surges from line-to-neutral are usually taken up by the PSU's own internal MOVs, spark gaps, and other things designed for the purpose (and far better than an average power strip of reasonable expense) of protecting the device. (Or at least this is the case with proper PSUs. No-name Ebay cruft without a UL/CSA/whatever registration is anyone's guess.)

Contrastingly, common-mode surges cannot be dealt with in this way....but they also can't affect anything unless that potential has someplace to go (ie, a complete circuit).

Which, of course, makes perfect sense: Stick one side or the other of a 9V battery against your tongue and nothing happens, but when you stick both sides to your tongue...ow.

So if your laptop was connected to two things (the wall *and* the hotel TV, or the wall *and* the Ethernet jack/phone line, or...), your failure makes more sense.

(and its mA when discussing current flow.)

Re:You're doing it wrong...

[gaiageek]

Questions:

1. How do you know it was a surge that killed your PSU?

2. What else was your laptop plugged into when it got roached?

I was in India (Goa) and was awoken in the middle of the night to the overhead fan spinning crazy-fast, like it was going to take off. Half-asleep, I tried adjusting the switch to put it on a lower level, but it had no effect so I just turned it off. During this I noticed the a light outside seeming unusually bright, but then someone stepped out and turned it off. I went back to sleep, not realizing that what just happened was a surge - and that my laptop was plugged in to the AC (and only the AC - no network cables or anything else). When I woke in the morning I noticed my laptop was running on battery power. I checked to make sure it was plugged in and noticed this - the surge protector (a laptop specific one). It fried it (and warped the plastic casing as you can see) and killed my Thinkpad PSU as well. The laptop was fine, though I have to wonder if it would have still been fine if the surge protector hadn't been there.

Now I know 1. the symptoms of a power surge and 2. not to leave anything plugged in and unattended when in surge-prone countries. But still I'm concerned about it enough to think about carrying surge protection.

The comments here have left me thinking that maybe I'd be just as well off, or better off, with something containing a replaceable fuse. I assume that a surge like that would've killed the fuse and left my PSU undamaged, and a few spare fuses weigh practically nothing.

Alternatively, maybe I should not worry about it and just have a spare PSU in a box ready to be shipped to me if need it.

Re:You're doing it wrong...

[itsme1234]

GGGP here :-)

First of all I'm surprised nothing more fried, especially from whatever other appliances the locals surely have.
To prevent damage from a simple overload yes a replaceable fuse and some MOVs would be the ticket; the only thing is that MOVs can absorb only so much energy and they get damaged at every hit (possibly the very first one). I don't know if anybody makes a commercial light (for travel) surge protector with replaceable fuses (maybe even MOVs). Probably it would be a nice project to make one yourself, the parts are quite cheap (and you can chose precisely what you want); the only problem would be the enclosure itself (maybe you can re-purpose one of the larger travel socket adapters). What works well in your advantage is the low power you need (for laptop and such), many surge protectors are rated for a lot of amps so they need a beefy fuse so it doesn't trip when you use your hairdryer for example...

However, I still wouldn't want to increase the complexity of my setup with some protection box, something that doesn't add any other features beside protection. As you mention India you might have noticed in any populated place they have people repairing everything, from laptops to mobile phones - they are sometimes doing complicated soldering jobs literally by the side of the road. Also "universal" laptop power supplies are usually available and they do work fine usually unless you have a particularly fancy laptop (I wouldn't let them plugged at home for sure but in a pinch they're better than nothing).

As for the USBs that don't charge things that are supposed to be charged by USB - I haven't seen for many years things that really don't work at all (I'm referring to things like phones, tablets, etc - stuff that needs to charge, not hard drives, that's another story). The laptops/desktops got better and better and giving power over USB and the devices themselves got better at accepting well under 5V inputs without stopping charging completely. If you want some insurance on this side I'd recommend a USB power bank, not a big one (unless you really want a big one), even one with only one 18650 battery would do (be sure to read some tests, many "numbers" are pure marketing).

If you get a good power bank you can recharge it from anything and power any of your finicky devices. You can also use it for more things than just the obvious, for example you can use it to firewall your device from strange USB charging ports (in the airport/planes/etc) - be aware not all power banks support charging and discharging at the same time, you can use it to "get some juice" without having the phone tied to the wall, etc.

Of course I didn't mean to drop your original charger. In fact my setup is the following:

- man purse - phone, small (but 2+A) USB charger, short cable, small powerbank

- laptop bag - laptop, laptop PS, long USB cable

Re:You're doing it wrong...

[Anonymous Coward]

I am an English teacher in China. If your laptop going down is going to cause issues carry a spare older machine. Use your spare in countries where the electricity is more prone to cause issues.

Re:You're doing it wrong...

[Anonymous Coward]

I plug my Apple power supplies (MacBook Pro, USB) straight into the wall and they're fine. I have a computer lab with 17 laptops all plugged straight in since 2009 and we haven't lost a single one to power quality issues.

We had a big collaboration meeting a couple years ago where about two dozen people went from the US to a meeting the UK. About half of them had Apple laptops, and there was something like 8 of those that borrowed laptops from a shared pool all bought at the same time. Several of the power supplies died instantly when being plugged into the higher UK voltage. Others using Apple laptops, even ones with the same model, didn't have any problem. We wondered if it was just a quality control issue, if a bunch of supplies sent to the US were not tested for operation above 120 V and it was just a bad batch.

Re:You're doing it wrong...

[adolf]

Alright, first I want to thank you for participating. I meant to do this before, but forgot. So often an Ask Slashdot happens, and the asker never interacts at all.

I can tell from your description that what you experienced was a surge from line to neutral.

Here's what's supposed to happen in any "surge protector" in this scenario:

The surge exceeds the breakover voltage of the MOV that is across line and neutral (which it must have, as it was the MOVs turning conductive that generated the heat that melted the housing). This does two things: It attempts to shunt the voltage, and also draws lots of current.

The circuit breaker (ever notice that the power switch on a surge-protected strip usually says On/Reset?) on the power strip is then supposed (via heating, electromagnetics, or both) to detect this excess ("lots") of current, and disconnect one leg of the mains. Once the breaker trips, things are supposed to be fine until reset, and then function normally (though MOVs do age as they get used like this and you should replace/repair the suppressor before absolutely trusting it again).

At least some of these things didn't happen. And sometimes, the MOVs get blown to bits by transient voltage, in which case they can't do anything further to help.

So. As much as I want to, and in fact did, say that a proper mdoern PSU should be reasonably unaffected by a line-to-neutral transient surge, apparently that wasn't the case here: Either its internal protection failed to be effective, or was effective briefly before being overwhelmed by the duration.

It might have sacrificed itself by blowing its own internal fuse: A post-mortem tear down is always a good idea with stuff like this, even if it involves taking it to the alley behind the hotel and paying neighborhood kids to pummel it with cement blocks until it opens. You'll see what's broken/fried/sacrificial, and learn to make better choices next time, and maybe come back and tell us all about it.

That all said: I tender the following three possible off-the-shelf solutions:

1. A Ditek surge suppressor. These are MOV and circuit-breaker based like most, but they advertise having lower breakover voltages than most others and are therefore more sensitive.

2. A Transtector surge suppressor. These are avalanche diode based unlike most, and are advertised to shunt surges earlier, faster and with more current capability than any MOV-based suppressor. They also use circuit breakers instead of fuses.

3. Someone here mentioned, I think, a Belkin design that includes a fuse, which is doubtless also MOV-based. Having a fuse seems low-tech, but fuses are generally -much- faster than circuit breakers and you can tailor the size of the fuse to your expected load, whereas a circuit breaker will always be sized for the maximum ampacity of the entire power strip. You'd want to install the smallest fuse you can get away with (buy a kill-a-watt or other thing that can measure current, too, to be sure). And you'll know if it's too small because it will blow inconveniently and often.

The idea with #3 is that the MOVs shunt the voltage, the fuse blows very quickly (much faster than a breaker), and there is no drama. Fuses are also much simpler and more reliable than $0.50 circuit breakers. Carrying a few extra (or a dozen!) fuses of different values shouldn't be a big deal as they are small and light and often come with appropriate packaging, and if they're AGC fuses (which they probably are) then you can find replacements literally anywhere on the globe.

IIRC, it comes with a 3A fuse. This seems totally appropriate for multinational use of a modern laptop with its 100-200W PSU, along with a small thing or two like a clock and a real cell phone charger.

(I really like #3, having thought this through for a couple of days)

Note, though, that in all cases (and for all countries!) you'll want to buy a 240V suppressor. I stand by and maintain that a global PSU will work with anything even rese

Surges weren't my biggest problem...

[aaarrrgggh]

Persistent over/under voltage was always my challenge traveling. A surge protective device doesn't do anything when power is running at 300V for a few seconds. The old MOVs, without proper fusing, would always pop and start smoking, which was a sign to trip the main breaker before everything got fried.

For truly sensitive electronics we always used commodity 12V chargers tied to a big battery bank with individual inverters for each piece of equipment. We might have had a custom filter to deal with ripple current off the chargers, too long ago to remember the details. The chargers lasted 2-3 months on average, but were easy to replace. Normal dual-conversion UPSs would barely last 3-4 months and were much harder to find and more expensive.

For today, I would have two laptop power supplies and an extra battery, and only charge from USB. The bigger USB power supplies are pretty robust, worth carrying extras.

Re:Surges weren't my biggest problem...

[phantomfive]

A surge protective device doesn't do anything when power is running at 300V for a few seconds.

Seriously? Is that actually a problem is some parts of the world?

Re:Surges weren't my biggest problem...

[Anonymous Coward]

Wow, unless you're advocating Linux or trolling Windows you're completely out of your element, aren't you?

Re:Surges weren't my biggest problem...

[Anonymous Coward]

Many surge protection devices are more of a con, fancy green light etc. I would recommend one that has actual fuses and over voltage protection. As suggested if you get a 240V device and all your equipment can handle 240v then it will be OK. A spare supply may also be handy.

Surges are very common, even in first world countries. Nearby lightning strikes on power lines, low voltages at the end of a long line in rural areas at peak times, power cuts followed by low voltages or high surges. Generally switch mode power supplies tend to be better at handling them. Ideally you want over and under voltage protection that disconnects the device when out of specification. Many UPS's do this and some can step up if needed.

You can get very small UPS's built into extension leads, and if it is good enough it may warn of problems. It may also save data in case of power failure.
Remember direct strike will damage everything. I have seen lights blown from walls. Back up your data off-site

Re:Surges weren't my biggest problem...

[Anonymous Coward]

Yes. But many switch mode power adapters handle it just fine.

Re:Surges weren't my biggest problem...

[aaarrrgggh]

Yes. In the course of a day, mains power where I used to live would range from 100V to 300V. You get the prolonged over voltages when a large load drops off, either a circuit breaker trip, or something more random. Modern voltage regulators prevent this, but legacy units will operate for a few minutes at 30-50% over voltage.

Even with modern voltage regulators, when the load is random they are often programmed pretty loosely. 3rd world load creates 3rd world grids.

Re:Surges weren't my biggest problem...

[phantomfive]

That's brutal

Re:Not what your asking for due to weight constrai

[gaiageek]

OP here. I see some GFCI single outlet adapters on the market, but no GFI (and I'm not sure of the difference). If it matters (I think it does), some of the places I've been have used outlets that aren't even grounded, which further complicates the whole surge protection defense of sending excess current to ground.

Here's a question: I have a cheap international plug adapter that has "surge protection" built-in in the form of a standard user-replaceable fuse. What about using that, and maybe even putting in a lower-rated fuse?

Meh.

[Anonymous Coward]

So this happened once and you're scared it will happen again, so you're going to weigh yourself down with extra crap every time you fly. Don't do it.

Consider a laptop that has an easily sourced replacement. MacBooks are ideal for this on two fronts: first the psu is physically much smaller than most pic equivalents in the first place (the MacBook is likely lighter than your laptop too, but that wasn't specified) and second you can likely get a MacBook psu in any major city in the world because they haven't changed for years and Apples are sold everywhere. Even in you're in Africa, you'll be able to get one in a couple of days.

Good luck finding the psu for any random pc laptop.

And if you're not osx guy, either install a VM for the os of choice or wipe OS X.

No need for 110V surge protection..

[Anonymous Coward]

There is no need for 110V surge protection if your power supplies are "Universal". You just need to protect them from the over 240V surges.
When I travel, All I have is one power board to fit all my plug packs, and then just one adapter to local power fittings.
Install 275VAC transient MOVs and a fuse and all should be ok, Maybe ;)

Re:Not what your asking for due to weight constrai

[jandjmh]

Most UPS's are "pass through" devices that connect the incoming power directly to the output if the input has power. When the input power drops, a relay inside the ups switches the outlets to an inverter that is powered by a battery. They provide no protection against surges, other than the same kind of limited protection that a powerstrip with surge protection has.

There are "online" UPS's that do a full double conversation (AC->DC->AC) at all times. They are heavy and expensive, but do provide nearly perfect protection to the attached gear.

Lots of Power Supplies Suck

[Anonymous Coward]

A device which is capable of powering various devices is the way to go. When traveling, I do not even take a laptop power supply just a Voltaic V72 . This is used to charge, razor (with a custom cable), phone, tablet, laptop and as a power supply for various projects which I typically I am working to complete / move along.

The best part of the V72 is that it is so versatile in regards to charging. I can charge from a car, plane, pretty much any laptop power supply (there are some limits). But I have used a range of power supplies including Fujitsu and Toshiba laptop power supplies to successfully charge the V72.

The biggest disadvantage is the size and weight of the device. However, if it saves you caring a couple of other power supplies it quickly compensates for this draw back.

Re:Not what your asking for due to weight constrai

[Trax3001BBS]

OP here. I see some GFCI single outlet adapters on the market, but no GFI (and I'm not sure of the difference). If it matters (I think it does), some of the places I've been have used outlets that aren't even grounded, which further complicates the whole surge protection defense of sending excess current to ground.

GFI's are required in the US in all newer homes, they are a fast tripping device, the outlet normally located in the bathroom. One outlet can protect an entire line.

Grounding protection is required for personal protection alone. If a country is too cheap to pay for the extra wire, I'd give serious consideration of using one's incoming metal water pipes as the third wire (think of the kids).

Here's a question: I have a cheap international plug adapter that has "surge protection" built-in in the form of a standard user-replaceable fuse. What about using that, and maybe even putting in a lower-rated fuse?

According to others replies your power supply should be well protected, situations like yours taken into account. The fuse a bonus allowing you more control. Amperage is your concern here, phones, computers, what have you; require a specific amp rating to charge, anything lower can take hours longer to charge if at all.

List of laptop surge supressors

[Aryeh Goretsky]

Hello,

Inline 100-240V laptop surge suppressors are readily available from online electronics retailers. Here are a few that will work for you:

• APC - APC Notebook Surge Protector for AC, phone and network lines, 3 pin connection, 100-240V
• CyberPower - CyberPower CPS500NBP Notebook Surge Suppressor - 500 Joules 2&3 Prong RJ11/RJ45 EMI/RFI
• Lindy - Laptop Surge Protector with USB Charger, Cloverleaf
• Tripp-Lite - Protect It! 2-Connector (C6, 3-Prong) In-Line Surge Protector, 306 Joules, Tel/Ethernet Protection

I've used the APC model without any issues, as well as models from Targus and TRC that has since been discontinued, but occasionally show up online for sale.

Regards,

Aryeh Goretsky

Re:List of laptop surge supressors

[gaiageek]

Yes, I'm aware of most of these (the Lindy one I hadn't seen). The point of my post though was that I'd like something that plugs directly into an outlet and has outlets for plugging in to, instead of something like one of these which are specific to laptops.

Must be rare failure

[Vadim Makarov]

Never had that happen to me, though I travel regularly. It must be a rare mode of failure. I have never lost a piece of equipment this way in any country. Just once I had to fix a N. American power stripe after its surge protector component smoked out in Europe. Bypassing it fixed the stripe and it run finely ever after :).

Personally I would not bother, as a failed power supply is not a big risk comparing to other risks that something else fails or gets lost. It may be more practical to rely on replacing the power supply from a local store in the event that it fails (many sell universal power supplies that fit sockets on most notebooks). If you are that paranoid, just pack a spare in your checked luggage.

Bring your own solar.

[Anonymous Coward]

Just bring your own solar power and forget the power conditioning problems. With the problems I read above sounds like you need more than just a surge protector. Sounds like you need a power conditioner and those can weigh a bit not something I'd want to pack around with. Maybe a fold-able solar solution might be lighter and more effective?

Only original power supply?

[gstoddart]

but this doesn't provide protection for a phone or tablet that requires the original power supply (can't be charged from a notebook USB port)

That sucks, because my suggestion was going to be to get something like this Kensington charger. I have one with the standard North American plugs, it works with 100-240VACm, 50-60Hz.

I have a strict rule ... down own anything which can't charge from stock USB. I find between my Kensington and a couple of 6600MAh USB power bricks, I can pretty much keep everything charged.

Things which require their own chargers just create more hassles in terms of what chargers you need to bring ... whereas bringing 5-6 USB cables of several different sizes and one or two good chargers is pretty damned easy.

Just say no to devices with proprietary chargers, because you can eliminate a lot of stuff with a decent USB charger which already handles the different voltages -- they're easy enough to find these days, relatively inexpensive, and help you cover a lot of cases much more conveniently.

Things are a whole lot easier when you just have some generic cables and a multi-port charger.

What I use

[RockDoctor]

I have multiple devices - more than a typical hotel provides sockets for. So I carry a 4-way or 6-way power extension lead for my home-country's type of wall socket. Then I have all the usual chargers (my laptop; company's laptop; client's laptop ; generic USB charger ; camera battery charger) , which plug into that. This works if I'm at work in my home country, at a clinet in my home country, at a client in their home country, or at work in any other country (e.g., where the client is operating).

I additionally carry ONE adaptor each for home-country to US ; and home-country to European "Shucko" (which is mostly compatible with Russian). And I carry a multimeter and a screwdriver - but I carry them normally anyway.

In combination, this then gives me 4 (or 6) sockets to my home country, in any country in the world. Well, any country I've met so far. I've occasionally had problems with only having South African sockets available.

Frequency

[NewYork]

You need protection surge against Voltage, Current and Frequency.
https://en.wikipedia.org/wiki/Utility_frequency