Oh.

I think here in the states you might more often encounter this as "Tankless Hotwater Heater" or at least "On Demand Hot Water".

Such a device, if electric, would draw several orders of magnitude more current than the Personal Computer. That could be a fire hazard. The computer, not so much.

Thanks, Keith.


--Mac

Besides for a good surge protector, check the weather forecast. No surge protector can stop a close lightning strike from toasting your computer.

Insights and incites by Notes

Mac has a point, most computers will draw around 400 to 500 watts of power while in use unless a super fast gaming rig with top end multiple graphics cards and power supply to match, even then a full 1000 watts is pushing the boundary a bit too far.

However as we in the UK do call them electric shower units as that is what they are intended to be used for, they are an on demand water heater, modern units can draw as much as 10 kilowatts, though the average will be around four to eight kilowatts units. That is here in the UK with our mains supply at 240 volts, a full 10 kilowatt unit will draw 41.6 amps, an 8 kilowatt will draw 33.3 amps, and so on. In countries where the supply voltage is 110 volts the current is over double that for 240 volts with nearly 100 amps for a 10 kilowatt unit. At those currents it only needs a slightly loose connection screw to overheat the connection to the point of fire breaking out.
Although a loose or poor connection will heat up and eventually cause fire in the supply to a computer, the instability of the computer due to the bad connection, will hopefully have prompted an early enough investigation to rectify it.
Having said that, there is still the chance of one of the higher current components in the computer power supply, could be a Friday afternoon lemon and burn out. The recent problems with electrolytic capacitors going pop due to the wrong electrolyte being used, could also be a cause of fire as once blown can become a short circuit.

Quite a few of the cheaper power supply units are regarded as incendiary bombs or combustive agents. Insufficent components (mostly: too cheap components) will overheat and then...

Also a otherwise safe component might become underdimensioned if components of a(n off the shelve) computer are exchanged to "more"powerful" ones. Most likely the PSUs of complete systems made by most manufacturers or assemblers have little reserve/cushion/spare (I don't know the right word).

If you want to be on the safe side: check the PSU in your computer and calculate the max. power needed and replace it -- if necessary -- to one that may deliver at least 20 per cent more performance than needed at the max. And buy the products of reliable manufactures only.

Guido

Aside from leaving your computer on/off, there are a bunch of other appliances that draw power,even on standby. With the cost of power these days, it might be advisable to unplug many of these when not in use. I found a handy way to check power consumption is to use a Kill-A-Watt meter. I use one to check power at venues before plugging anything in. It's also handy for calculating power draw on a given circuit to prevent overloading.


http://www.p3international.com/products/special/p4400/p4400-ce.html

Yes, they usually are encased with quite a few openings into the PC case. The air to cool the PSU comes more often than not from inside the PC. Even if the fan sucks air out of the PC, once the PSU starts to burn the fan will stop soon after. Depending on where in the PC the PSU is located and whether the PC case is made from metal or other material.

I'm not saying each and every cheap PSU will cause fire, many of them are known as Chinese firecrackers.


While a burning PSU destroys itself -- it might find some empathic companions for the trip towards Nirwana...


Guido

I'm a little skittish about high voltage (defined as 120 VAC or above) and dust. I once had a 100A three-phase breaker box that I had personally locked in the off position blow up in my face. By the grace of God I wasn't injured in the least, but there was a hell of a bang. We later figured that dust falling through the contacts ahead of the breaker had caused a short. (After that I started wearing a face shield while working on electrics.)

My point is that an overheated PC is likely to cause problems, and that overheating is likely to be caused by dust. My concern is that the dust may ignite and be blown outside the PC case by the PSU fan, possibly setting fire to something in the room. This is perhaps a bit baroque, but are you willing to bet the safety of your home or studio on its not happening?

Far better to be safe than sorry. Clean the inside of your PC regularly and make sure, as stated above, that the power supply is rated at least 20% in excess of the sum of your system's component draw. In fact, inrush current on startup can briefly run 30% above steady state, so more is better. Lastly, if your house wiring isn't already so equipped, you may want to make sure that your surge protector has ground fault interruption (GFI). If you don't do these things, at best the CPU or PSU will fail sooner than expected, and at worst--catastrophe.

Signed,

Lemony Snicket (See A Series of Unfortunate Events)

:P

I spent many years as an certified Fire and Explosion investigator. Never saw a computer that caused a fire. A bit of smoke an few times, once my own 5 grand 5 meg hard drive, it filled the office with black smoke but only a resistor burned and it was tiny, and my drive worked for two more years. I've seen whole apts wired with Electrolux wire the owner fixed them and re used the wire. One nite out for last call at a local, the stereo caught fire. 85 feet of Electrolux cord to a plug and that of course dropped the voltage and now you apply Ohms law.
Magazines on top of the stereo and...bingo. Fire. Two hundred thousand insurance claim and a four plex that was supposed to be a duplex least ten homeless and killed 4 pets. No detectors worked.

Like a lot of home made car stereo systems.. Ummm no sir only thing I've done to my sweet ride was add a big stereo, you should have seen the headlights dance when the bass was grovin moved them lights up and down shaking my car. Geez. Son you needed to pop a cap in that ride! Electrical joke there.


Keep your fan clear, don't pile stuff on top, and just do like me, turn it off when you move it.

Well, this forum has passed another milestone: now we have electrical jokes. Watt's up with that?

ohm my...

Why, err . . .