High-po PSUs and household wiring - safety issues?

PSUs: The source of DC power for all components in the PC & often a big noise source.

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Herb W.
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Joined: Sun Sep 15, 2002 8:35 am
Location: Toronto

High-po PSUs and household wiring - safety issues?

Post by Herb W. » Thu May 31, 2007 4:52 pm

I am hoping that someone with a good grasp of household wiring issues can help me here. I am looking at getting a Seasonic M12 for an SLI system I'm building that at full load at the wall will draw up to 650+ watts. I live in a condo with no real flexibility to improve my wiring. The computer will be on either a 15 or 25 amp line. Do I need to be concerned about blowing fuses or overheating the wiring? I see these huge amp ratings in the PSU reviews - eg 40 amps on the 12 volt rail - and that is way above the fuse rating for my lines. But I presume that these are irrelevant as they apply to the stepped down voltages, it's the amp draw at the wall I need to concern myself with, which will be 700 watts/120 volts or about 6 amps--so I should be fine as long as I don't overload the line with other uses (eg space heaters)? Anything I'm missing here? I don't want to spend a fortune on a new box only to find I can't use it! :shock:

TIA for any guidance.

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Joined: Fri Jun 18, 2004 6:53 pm

Post by JazzJackRabbit » Fri Jun 01, 2007 9:15 am

You shouldn't worry about 15amp rating. The 40amp figure (which is grossly exaggerated) is for 12V line, so that's 40A*12V = 480W. The 15 amp rating on the fuse is for 110V (or whatever you have in Canada). Assuming it's 110 volt, that fuse should handle 15A*110V = 1650 watts of power. So you should be safe as long as your wiring is good and as long as you don't overload that fuse.

Khrono Devil
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Joined: Sat Jun 02, 2007 2:18 am
Location: New Zealand

Post by Khrono Devil » Sun Jun 03, 2007 9:34 pm

At most with 2x 8800GTX, QX6700 OCed -> 3.5Ghz, 4GB ram, 2 HDD, 1 DVD and Pump my computer uses around 600W at the wall ( Don't forget about monitor thats another 130W for 27" LCD )

Like Jazz said 15amp x 110V = 1650 watts, as long as you don't plug to much into the same circuit you will be fine.

As for the power supply I have no experiance with the Seasonic M12 PSU, but for around the same price you could get the Corsair HX620 which easily and quietly powers my system (the one above) and has alittle wattage left if I want to add anything extra.

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