Two transformers on one AC plug?

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I'll be housing multiple amps in the same enclosure and I'm wondering if I can hook up multiple transformers to the same AC plug on the chassis. They will all be on/off at the same time, so I'm not worried about that.

Yes you can, and it is done frequently. The only thing to watch out for is the mains side fuse. One fuse per transformer would be ideal, particularly if there is one huge transformer and one small one, when a fuse large enough for the biggy would not be offering much protection for the small one.
 
As long as they do not exceed the rated loading of the AC circuit (15Amp in NA), why not. You could fuse each transformer seperately to aid any troubleshooting down the road. E
Since you brought up loading of the circuit, is there a max wattage that can be handled in NA? or is it up to the duty of the circuit breaker. I'm wondering if I'll trip the breaker when I put this in my dorm room.
 
Your PC should be fine.

We recently moved from having an old 'fuse box' that actually had wire fuses in and powering any large transformer was never a problem. We changed over to one with circuit breakers and every large transformer in the house would trip the breakers on powering on. A soft-start circuit was required to circumvent this, obviously a soft start is useful for other reasons beyond tripping the primary breaker, but still, bare this in mind.
 
Full load it draws 1.6 kilowatts. Very unlikely that I'd ever push that much load at one time with audio and pc equipment, but I don't want to risk it. I've got a laptop I can take, but that PC is what I do all my graphic design and CAD work on. However, it does draw all that power at startup and often causes lights to flicker.
 
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Have you measured the PC drawing 1600 watts, or is that the theoretical maximum for the PSU?
Measured draw under full load is usually about 1480 but has gotten above 1500 before. It's tough to get all the graphics cards and the processor up to full load at the same time. Not to mention all the fans which fluctuate in speed even when set to max. So I assume it gets pretty close to the theoretical max when I'm doing big render projects or fluid dynamics.
 
I was going to say, getting up to 1500 watts is quite impressive and most certainly likely to be rather transient instead of continuous draw. I wouldn't worry about running the PC in combination with the hifi, most music will only draw large amounts of current for small peaks, so unless you want to do full sine wave testing whilst you're doing fluid dynamics then I wouldn't worry.

What watt rating do electric fires typically have over there? In the UK 3kw fires are common place. I regularly run the 3kw fire + computer + hifi without any issues, in fact the circuit breaker for my room powers another room too which can use electric heating from time to time, we've had the breaker go when someone decided to use a hair dryer on top of that, but that's extremely rare. I'd be surprised if a wall socket couldn't support a continuous 3kw load.
 
I was going to say, getting up to 1500 watts is quite impressive and most certainly likely to be rather transient instead of continuous draw. I wouldn't worry about running the PC in combination with the hifi, most music will only draw large amounts of current for small peaks, so unless you want to do full sine wave testing whilst you're doing fluid dynamics then I wouldn't worry.

What watt rating do electric fires typically have over there? In the UK 3kw fires are common place. I regularly run the 3kw fire + computer + hifi without any issues, in fact the circuit breaker for my room powers another room too which can use electric heating from time to time, we've had the breaker go when someone decided to use a hair dryer on top of that, but that's extremely rare. I'd be surprised if a wall socket couldn't support a continuous 3kw load.
To be honest I have no idea. I'm sure it varies by model, but the dorm I'll be staying in was built in the 70's. Granted, it's been renovated, but I doubt they changed all the heaters. If my room has an individual breaker, then I'll be fine. But I have a feeling that at least two or three rooms, if not more, will be on the same breaker. Not sure, though. The other issue is size. My computer is an 18" cube and runs at 48dB (and I'm not even done installing fans!).
 
Measured draw under full load is usually about 1480 but has gotten above 1500 before. It's tough to get all the graphics cards and the processor up to full load at the same time. Not to mention all the fans which fluctuate in speed even when set to max. So I assume it gets pretty close to the theoretical max when I'm doing big render projects or fluid dynamics.

Are you sure about this??

1500W is a huge load and, since 95% of it is used up as heat, your PC will be glowing red hot!

200W for a modern loaded PC, up to 300W with macho graphics cards is what I experience. Fans are <10W each.

Measure it with a cheapo plugin watt/VA meter.
 
Are you sure about this??

1500W is a huge load and, since 95% of it is used up as heat, your PC will be glowing red hot!

200W for a modern loaded PC, up to 300W with macho graphics cards is what I experience. Fans are <10W each.

Measure it with a cheapo plugin watt/VA meter.

This is a little out dated. Top line current generation graphics cards can draw 350 watts + just on their own. Put two in SLI/crossfire and you're up to 700+ watts just for the two cards. Processors can vary, but 75 watts is probably a safe nominal figure. Of course you've then got all the other hardware that the PC is running too + losses in the power supply. Fully loaded and including the monitor it could get up to around the 1500 watt mark.

Frosteh, what hardware does your PC contain as this might give a better idea of what it might draw.
 
I am a little outdated!

However I would contend that 1500W dissipation in a cabinet the size of a tower PC is not feasable domestically. Either running red hot or with a "hair dryer blast" out of the rear.

Most PCs have <500W PSUs, for everything. Most idle at 75 to 150W but of course have peaks. I repair lots of these.

=> 1KW PSUs are quite hard to find.

Most specs give the max required, so adding up fans, discs, m/bs etc gives a very high figure.

My nephew's gaming station has twin video cards with noisy fans. These add only 50W idle to the total power used.

In any case, AFAIR the OP says he measured it at 1500W. I don't know how he thinks he did this but I am sceptical.

Spend $10 on a plugin power meter. It will give instant VA and W. (as well as V, I, f and pf!) and avoids all this speculation! This is what I use:
 

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I am a little outdated!

However I would contend that 1500W dissipation in a cabinet the size of a tower PC is not feasable domestically. Either running red hot or with a "hair dryer blast" out of the rear.

Mine isn't a hair dryer blaster but it does get hot around the back when the graphics card is going full tilt, the entire back mounting section gets very warm and the air exhausted by the rear case fan is more then a little warm. Ive also got an ATCS840 case from cooler master, which is one of the better cases when it comes to replacing the warm air inside the case with cold air from outside.

Most PCs have <500W PSUs, for everything. Most idle at 75 to 150W but of course have peaks. I repair lots of these.

Indeed, it's intensive graphics hardware that places huge demands on the PSU.

=> 1KW PSUs are quite hard to find.

Yes this is why the larger cases, designed to cater to the overclockers etc, have room for two PSUs, my case included, although I only use one PSU.

In any case, AFAIR the OP says he measured it at 1500W. I don't know how he thinks he did this but I am sceptical.

Spend $10 on a plugin power meter. It will give instant VA and W. (as well as V, I, f and pf!) and avoids all this speculation! This is what I use:

I agree I am sceptical too, but he might just have a plugin power meter already ;)
 
Dual GPU cards can dissipate 500W+ (the new AMD 6990 does). Put four of those together (or their FireGL equivalents) for engineering processing/rendering purposes on a server board and you're looking at 2KW right there. Processors can dissipate 130W peak.

Put together a quad socket quad video card processing/simulation/rendering powerhouse and you're easily looking at 2.5KW powered by dual PSUs. 1.5KW supplies are easily available from Delta and such for rack server applications. You can then overclock if you want more heat. :D
 
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