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| Thread ID: 33870 | 2003-05-28 00:19:00 | POWER Overload? | sc0ut (2899) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 148049 | 2003-05-28 02:21:00 | When there is a power break, and it comes up again you will probably pop a fuse (or circuit breaker). What will get you is the starting surge. That could easily be 30 - 50 amps each, as they charge the 200 or so microfarad capacitors to 330 V DC. (This depends on the point in the cycle when the power is connected again ... if you were "lucky" it might be at the zero crossing, and it would be much nicer. But you won't be. :D) When it happens, turn all of the computers off. Then when the power recovers, start each of them in turn. That's a good idea anyway. When power is restored, there can be lots of surges and spikes coming through. |
Graham L (2) | ||
| 148050 | 2003-05-28 03:10:00 | When the power went off in my house and it came back on again, my computer would power up again automatically. Maybe not the best idea with the surges you talk about. There should be a setting in the BIOS to stop the comp from powering up after a power failure. | PoWa (203) | ||
| 148051 | 2003-05-28 07:04:00 | most of the time the pc's wont be at full draw. they are normally only at full draw on startup (exspecially with crt monitors). zap catchers ??.......over priced pos ;-) ....get some decent spike protectors and some decent ups's would be a good ad on. one thing to watch is how warm the cable (extention leads) get. also most 4/6 way powerboards have 10amp cutouts on them. |
tweak'e (174) | ||
| 148052 | 2003-05-29 05:23:00 | I agree ... most of the time you'll be fine. But the instant of power on to the whole lot simultaneously (after a power break) is the one where problems will occur. A quick look on google using "axt psu inrush" found a few specifications ... the range of the few I looked at was between 20A and 100A. :D Of course those are only "specifications". It could be worse. :D | Graham L (2) | ||
| 148053 | 2003-05-29 06:00:00 | Just reflecting on your post Graham, while the inrush current could theoretically be quite high, in practice I don't think it would be that bad as the impedance of the supply would probably knock it back. Seven computers into two outlet points doesn't go unless some adapters or powerboards are in use, and they are inclined to be quite lossy due to poor contact tension and lightweight conductors in the power leads. Then there is the length of cable back to the switchboard to consider. I think that a 20 Amp CB would easily handle the surge current, but with electronic power switching on ATX supplies, do they automatically come back on after a power outage? If they don't, the simultaneous switch-on of seven computers is unlikely to ever happen. Of course the simultaneous switch on of seven monitors and attendant degauss surge could be another factor. Maybe I'll do a peak current check on old faithful and post the results. They might make interesting reading. Cheers Billy 8-{) |
Billy T (70) | ||
| 148054 | 2003-05-29 06:10:00 | I assume that the ATX supplies charge up the 330V capacitor unconditionally, and make a trickle of 5V for the "power switch" and the wakeup logic circuits (plus a few hundred mA for a wakeup Ethernet card, or modem) . It's them microfarads (which are a dead short at turn on) and a rectifier across the mains input which gives that initial inrush . (I know the power boards can be fairly resistive, but the house supply should be able to give 6000 amps -- briefly -- and if his 7 supplies all want 100 A inrush, a few things could be "tested") . |
Graham L (2) | ||
| 148055 | 2003-05-29 06:12:00 | Interesting to see people so concerned about power. To add to everyone else the cpu is not the big power waster on your computer its your monitor. If your all playing a game (that increases CPU utilisation) your looking at about 2W per pc. so 14w over the 7pcs. Nothing to be alarmed at, |
roofus (483) | ||
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