Air conditioners kill hard-drives

[Mehen]

http://theinquirer.net/default.aspx?article=39512

hrm, wonder if its true. The logic seems sound.

[MultimediaMan]

Power Line conditioners and UPS units will mitigate this risk. Newer hard disks with their higher data densities and large caches may well be more susceptible.

Most SOHOs don't maintain their UPS units; more still don't even have them.

[VJ]

Well, the website of MGE (UPS manufacturer) has a selector to determine how much you are at risk. It takes into account the presence of air conditioners, copiers, lift, heavy machinery (welding equipment), etc. While this could be marketing mumbo-jumbo (they sell power line conditioners and UPS units), I do think there is truth to it.


Jörg

[az]

A good PSU should protect the PCs innards from surges, and should commit suicide on a surge before allowing it to pass into the PC. I also can't see how ACs would cause surges - wouldn't they rather cause power loss? (which a good PSU with large enough caps can also stabilize, if they're short)

And then, why only Hard Drives? And what about fridges? Or electric ovens? Or vacuum cleaners?

[VJ]

A good PSU

Bingo!
But there are many "average" PSUs out there...

I also can't see how ACs would cause surges - wouldn't they rather cause power loss? (which a good PSU with large enough caps can also stabilize, if they're short)

The compressor of an AC is not necessarily running all the time, but starts and stops depending on the needs. Esp. starting such a device usually causes some fluctuations (these also occur when for instance switching on a crt monitor, as can be seen on some UPS's).

And then, why only Hard Drives? And what about fridges? Or electric ovens? Or vacuum cleaners?

I suspect this can be traced back to the PSU. Fridges are similar in that aspect to ACs (compressor that starts/stops); electric ovens draw lots of power, but don't usually have a sudden spike of power use. I guess common household devices can cope quite well with power spikes.


Jörg

[Umfriend]

I assume electric ovens to show a sudden spike when switched on, no?

[az]

And vacuum cleaners not only draw lots of power, they are also an inductive load, like I assume ACs are (if this even makes a difference).

I still can't see where surges (voltage spikes, temporarily higher voltage) would be generated by turning something on.

[VJ]

I know it is one of the reasons it isn't recommended to put laserprinters on a UPS (depending on the technology behind the UPS)...


Jörg

[az]

Laser printers draw lots and lots of power (into the kilowatt range).

[Technoid]

Laser printers draw lots and lots of power (into the kilowatt range).

My coworker put a watt meter on his new color laser and the results gave him nightmares

[Jon P. Inghram]

I wonder how accurate of a measurement of power supply quality it is to test how long the computer stays on when unplugged.

[spadnos]

And vacuum cleaners not only draw lots of power, they are also an inductive load, like I assume ACs are (if this even makes a difference).

I still can't see where surges (voltage spikes, temporarily higher voltage) would be generated by turning something on.

It's actually the turn-off that gets you

Running motors have stored kinetic energy in them, so when you want to stop the rotation, you have to take out the energy. Since motors are also generators, the energy removal generally takes the form of an electrical spike, since the inductive nature of the motor wants to keep current constant (and voltage will increase due to the resistance in the electrical feed wires).

So ACs, refrigerators, vacuums, fans (to a lesser extent), hair dryers, pumps ... all cause problems when they cycle off.

- Steve

[az]

Thanks steve.

Jon, It would be an accurate test of brown-out protection if you could measure well enough, but since it would only be fractions of seconds I doubt that you could