Power factor comes from the fact that CFLs are not a purely resistive load. But energy stored in a capacitor or inductor is not lost.
In this case the energy is not returned like with an inductive or capacitive load. Cheap electronic ballasts (and any cheap switching power supply) use a rectifier and capacitor combination to produce the internal DC bus voltage. The poor power factor does not come from an out of phase inductive or capacitive load but from a nonlinear load which draws power at harmonics of the AC voltage. The RMS current is higher than necessary for a given amount of power so the line losses are also higher than necessary. The utility has no way to compensate for this type of load other than building their infrastructure to handle the added transmission losses. Compensation has to be at the device end and takes the form of passive or active power factor correction. CFLs with power factor correction are a little more complicated and expensive.
Oddly enough, very old style tube rectifier based power supplies used a series inductor to limit the peak current giving them a better power factor but not because of power distribution concerns.
The downside to most geoengineering projects, however, is that they're merely masking. Most of them -- not all, but most -- simply try to hide the effects of one symptom of CO2 rise or another (usually the heat, ignoring the ocean acidification).
If we bought one of those Outsider drives we could just move the Earth further from the Sun. I know they are expensive but maybe we could arrange a payment schedule or something.
Power supplies without active power factor correction use a full wave rectifier feeding a large input capacitor. The only thing they care about is peak voltage. You can run them from at least 50 to 400 hertz without issues of any kind and since they use a voltage doubler for 120 volts AC, they will also run fine on 340 volts DC. The only issues are that their poor harmonic related power factor is hard on some generating equipment (VA verse watts) and the ones with automatic input range switching could have problems if they get confused about what range to use.
Some active power factor corrected power supplies are poorly designed and expect at least something resembling a sine wave at roughly the correct frequency. The well designed universal input ones will run on 90 to 270 volt AC or the appropriate level of DC up to 340 volts with any reasonable wave shape or frequency.
The geometry is significant. For an early warning, the sensor has to be closer to the epicenter than you are and you have to be located some distance from the epicenter. With the southern California network more than 10 years ago, warning times were more than 10 seconds and left plenty of time for me to take action. Of course latency on that system was on the order of milliseconds.
Or more weight in the form of more wire requiring a higher voltage. Rare earth PM motors may have a power to weight and volume advantage but they are not going to be significantly more efficient.
The element that has been holding them back is processing speed of the drive cpu's and the electronics themselves. Right now there are "notchy" at startup.
The processing and control requirements look no greater than that needed for vector controlled AC drives and those have been around for at least 20 years.
With some type of position encoding, I am certain even a 20 MIPS PIC microcontroller could handle it with appropriate hardware. If they are having performance problems with ARM, then they are using the wrong programming language.
Modified SIN wave stepper drivers that compensate for the nonlinear inductance to prevent cogging have been around for a long time as well but they are only used in the highest performance applications. Switched reluctance motors are just a more extreme case.
Are you an undercover cop? No? So your weapon is for "protection" and not merely to make you feel like you have a ten foot long penis - why then don't you have it where it can been seen and let that help with protecting you?
Because my concealed carry permit does not apply to open carry which is largely unlawful in my area.
How much confusion has their been over the existing 0.1, 0.5, and 0.9 amp power levels? On the other hand, self powered IEEE 1394 interface devices are a compete failure so far as I know.
Hopefully they will mark the ports in a distinctive colorblind way.
That better be an incredibly efficient up converter.
Non-isolated boost converters are about the most efficient switching regulators and easily achieve greater than 98% efficiency.
On the human safety issue, prices will be driven up by necessary certifications. Usually works or nearly always works may not be good enough anymore. It will have to absolutely positively provably shut off every time.
Isn't the low voltage certification just about 48 volts?
I would use both the differential pair biasing and the idle clock to enable the high voltage supply at a hardware level. That only leaves someone damaging a cable in such a way that all 4 conductors are neither open nor shorted.
I was actually thinking 30 or 48 volts derived from a simple step-up converter that is under control of the USB host controller. 30 volts is more convenient because integration on both ends is easier although 48 volts is possible without discrete semiconductors. The output is going to have to be monitored anyway since not all hosts are going to be able to provide the maximum power from the specification.
Next up, people have gotten used to the idea of peripheral cables that can't hurt you, even if you (or your small child) hold the end in your mouth. That would no longer be quite the case.
If the high power output requires enumeration, then disconnecting the cable will conveniently shut it off.
I do not understand the problem here. If you connect any legacy device including a hub, then the high power capable USB port will not raise the USB bus voltage and higher power will not be available because the enumeration required for high power support will not occur. It does not matter what downstream devices do.
This new standard seems like it would simply be a polite codification of this confusion. Particularly at low voltage, 100watts is nontrivial current(and nontrivial power generally, most non-DTR laptop bricks are less than that...) Many PCB layouts would burn a trace trying to deliver that, and you can bet that your garden-variety 10-USB-ports boring desktop isn't going to ship with 1000watts of PSU headroom...
I suspect the new standard is going to involve raising the USB bus power pin voltage after enumeration if they want to supply anything more than the current 4.5 watt maximum. That leaves devices which do not enumerate out of the picture, saves the PC board traces, connectors, and cables, and leaves it up to the powering device to decide if power is actually available.
Devices which lie during enumeration could be in for one hell of a surprise, err, shock though.
The Firewire situation is a shame. It even had the capability of powering large external hard drives. eSATA is almost as bad.
But that is ok since no civil rights are impacted and it is just an inconvenience:
"A driver's license is not a matter of civil rights. It's not a right. It's a privilege," she said. "Yes, it is an inconvenience [to have to clear your name], but lots of people have their identities stolen, and that's an inconvenience, too."
Microcontroller development kits often do not implement all of the power modes available and even if the hardware supports them, the included software and libraries may not. ARM microcontrollers in particular have had a number of serious power mode (and I/O race condition) bugs over the years.
I have had to either design and build my own ARM prototypes to implement the features I want or use other microcontrollers like PIC. I had to disqualify Arduino for lack of hardware feature support as well. I laugh when they try to implement a less than 1mA low power mode and then include a high quiescent current regulator to power it or leave no way to power down external support circuits.
Most off the high volume embedded development kits look like something designed by a programmer first EE second. I can usually spot design flaws within seconds of examining the schematic. Power on reset circuit errors, multipoint analog grounds, inadequate temperature range oscillators, and inadequate ESD and overload protection are more the rule than the exception.
At some point, they have to admit it into evidence. At that point you show the judge the law against NSA conducting operations against Americans, and they go to jail instead of you.
The State Secrets Privileged would prevent court review.
Now if you submit the dead home invader who inexplicably has Federal credentials . . .
NSA wouldn't run a counterintelligence operation against Americans. That would be illegal and easy to beat.
If they did, how would you ever prove it?
Bait them with a canary trap.
If you succeed, there will be plenty of evidence although the State Secrets Privilege makes it moot unless your evidence includes a captured or dead agent and maybe not even then.
Where I am in Missouri, we generally have 2 or 3 short duration and 1 long duration blackouts per year not counting power loss due to weather. The ice storm a couple years ago knocked out power for almost a week during continuous sub zero F weather. A gas furnace is useless without power for the blower motor.
I have a small gas powered backup generator, several online UPSes, and am considering a larger backup generator.
There's a really nifty generator setup - I don't recall how it's constructed, but it uses AC power for magnetization, and when run it will automatically generate AC power that is in sync with the magnetization current.
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That whole fiasco with not being able to use all of the RDRAM slots on a motherboard because of poor reliability did not help them any.
I avoided them just because of their sleazy business practices. I did not care if what they did was legal or not.
In this case the energy is not returned like with an inductive or capacitive load. Cheap electronic ballasts (and any cheap switching power supply) use a rectifier and capacitor combination to produce the internal DC bus voltage. The poor power factor does not come from an out of phase inductive or capacitive load but from a nonlinear load which draws power at harmonics of the AC voltage. The RMS current is higher than necessary for a given amount of power so the line losses are also higher than necessary. The utility has no way to compensate for this type of load other than building their infrastructure to handle the added transmission losses. Compensation has to be at the device end and takes the form of passive or active power factor correction. CFLs with power factor correction are a little more complicated and expensive.
Oddly enough, very old style tube rectifier based power supplies used a series inductor to limit the peak current giving them a better power factor but not because of power distribution concerns.
If we bought one of those Outsider drives we could just move the Earth further from the Sun. I know they are expensive but maybe we could arrange a payment schedule or something.
Nobody should be using that small a cooling margin and in any case, the nonlinear losses are lower with DC making up for much of the difference.
What?
Power supplies without active power factor correction use a full wave rectifier feeding a large input capacitor. The only thing they care about is peak voltage. You can run them from at least 50 to 400 hertz without issues of any kind and since they use a voltage doubler for 120 volts AC, they will also run fine on 340 volts DC. The only issues are that their poor harmonic related power factor is hard on some generating equipment (VA verse watts) and the ones with automatic input range switching could have problems if they get confused about what range to use.
Some active power factor corrected power supplies are poorly designed and expect at least something resembling a sine wave at roughly the correct frequency. The well designed universal input ones will run on 90 to 270 volt AC or the appropriate level of DC up to 340 volts with any reasonable wave shape or frequency.
All flavors of USB have DMA but they require the CPU to setup the transfer while with Firewire it can be initiated from the device.
What is the chance that the same software update will disable both of them?
The geometry is significant. For an early warning, the sensor has to be closer to the epicenter than you are and you have to be located some distance from the epicenter. With the southern California network more than 10 years ago, warning times were more than 10 seconds and left plenty of time for me to take action. Of course latency on that system was on the order of milliseconds.
Or more weight in the form of more wire requiring a higher voltage. Rare earth PM motors may have a power to weight and volume advantage but they are not going to be significantly more efficient.
The processing and control requirements look no greater than that needed for vector controlled AC drives and those have been around for at least 20 years.
http://en.wikipedia.org/wiki/Direct_torque_control
With some type of position encoding, I am certain even a 20 MIPS PIC microcontroller could handle it with appropriate hardware. If they are having performance problems with ARM, then they are using the wrong programming language.
Modified SIN wave stepper drivers that compensate for the nonlinear inductance to prevent cogging have been around for a long time as well but they are only used in the highest performance applications. Switched reluctance motors are just a more extreme case.
Because my concealed carry permit does not apply to open carry which is largely unlawful in my area.
How much confusion has their been over the existing 0.1, 0.5, and 0.9 amp power levels? On the other hand, self powered IEEE 1394 interface devices are a compete failure so far as I know.
Hopefully they will mark the ports in a distinctive colorblind way.
Non-isolated boost converters are about the most efficient switching regulators and easily achieve greater than 98% efficiency.
Isn't the low voltage certification just about 48 volts?
I would use both the differential pair biasing and the idle clock to enable the high voltage supply at a hardware level. That only leaves someone damaging a cable in such a way that all 4 conductors are neither open nor shorted.
I was actually thinking 30 or 48 volts derived from a simple step-up converter that is under control of the USB host controller. 30 volts is more convenient because integration on both ends is easier although 48 volts is possible without discrete semiconductors. The output is going to have to be monitored anyway since not all hosts are going to be able to provide the maximum power from the specification.
If the high power output requires enumeration, then disconnecting the cable will conveniently shut it off.
I do not understand the problem here. If you connect any legacy device including a hub, then the high power capable USB port will not raise the USB bus voltage and higher power will not be available because the enumeration required for high power support will not occur. It does not matter what downstream devices do.
I suspect the new standard is going to involve raising the USB bus power pin voltage after enumeration if they want to supply anything more than the current 4.5 watt maximum. That leaves devices which do not enumerate out of the picture, saves the PC board traces, connectors, and cables, and leaves it up to the powering device to decide if power is actually available.
Devices which lie during enumeration could be in for one hell of a surprise, err, shock though.
The Firewire situation is a shame. It even had the capability of powering large external hard drives. eSATA is almost as bad.
The component failure mode was "disappearance".
What part of "do not advertise this" is beyond your puny comprehension? - Hindmost
Last time I did that to cancel my Earthlink DSL service, they renewed it which prevented re-provisioning.
I added that to my list of reasons for canceling when I called them the next two times.
Probably the same ones that revoke your drivers license if you have the wrong face:
http://www.boston.com/news/local/massachusetts/articles/2011/07/17/man_sues_registry_after_license_mistakenly_revoked/?page=full
But that is ok since no civil rights are impacted and it is just an inconvenience:
"A driver's license is not a matter of civil rights. It's not a right. It's a privilege," she said. "Yes, it is an inconvenience [to have to clear your name], but lots of people have their identities stolen, and that's an inconvenience, too."
Microcontroller development kits often do not implement all of the power modes available and even if the hardware supports them, the included software and libraries may not. ARM microcontrollers in particular have had a number of serious power mode (and I/O race condition) bugs over the years.
I have had to either design and build my own ARM prototypes to implement the features I want or use other microcontrollers like PIC. I had to disqualify Arduino for lack of hardware feature support as well. I laugh when they try to implement a less than 1mA low power mode and then include a high quiescent current regulator to power it or leave no way to power down external support circuits.
Most off the high volume embedded development kits look like something designed by a programmer first EE second. I can usually spot design flaws within seconds of examining the schematic. Power on reset circuit errors, multipoint analog grounds, inadequate temperature range oscillators, and inadequate ESD and overload protection are more the rule than the exception.
The State Secrets Privileged would prevent court review.
Now if you submit the dead home invader who inexplicably has Federal credentials . . .
Bait them with a canary trap.
If you succeed, there will be plenty of evidence although the State Secrets Privilege makes it moot unless your evidence includes a captured or dead agent and maybe not even then.
Where I am in Missouri, we generally have 2 or 3 short duration and 1 long duration blackouts per year not counting power loss due to weather. The ice storm a couple years ago knocked out power for almost a week during continuous sub zero F weather. A gas furnace is useless without power for the blower motor.
I have a small gas powered backup generator, several online UPSes, and am considering a larger backup generator.
http://en.wikipedia.org/wiki/Doubly-fed_electric_machine