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

[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

[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.

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.

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

[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: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.