Max Pull Per Breaker?

[elrodvoss]

I have been looking at various multi-rig set ups and i wonder how they can have all those system in one room and not trip breakers?

I understand that a standard house and breaker can support about a 1440 watt pull.  With most of these systems using a 1200W psu, I understand that the computer will not pull 1200w 24/7, but with setups that have 2-3 setups have to be exceeding what one breaker can support.

I have a very basic knowledge of this, so I must be missing something.

Doing a little research I found out that the 5850 will pull around 305w under load at the outlet.  AMD's website states that the card requires two 75w 6 pin pci-e, which would pull 150w max, plus the port its self.  So something of my research is flawed. 

Any insight would be helpful.  Thanks.

-Elrodvoss

[Stokkie]

As far as I know that 305Watt is probably the whole system without the monitor but you wouldn't need a 1200W psu in this case unless you put 3 cards in one system which would work on your breaker.

Also I'm not sure where u are from but in the EU 16A breakers are pretty much standard which give you 16A*230V = 3680W, in some cases 10A is used, then you still have 2300W.

[fourd00rgtz]

I had to find out the hard way that the builder of my condo cheaped out and wired the wall outlets from both bedrooms on the same circuit.

I cant run 2 miners (7x6950's) a Folding @ home Quad G34 rig, and 2 14000btu AC units, with 1 AC off, I can blow the breaker just by turning on a plasma tv thats on the same circuit.....

So My next rig is getting build in the kitchen, yep cuz each outlet is on its own breaker.

[Epoch]

In the US and Canada, the Electrical Code stipulates a normal 120V household outlet to have a 15A breaker. That's 1800W peak. But for continuous loads, it cannot exceed 80% of peak. That's where the 1440W comes from.

For continuous loads beyond 1440W, the following are common:
- run separate circuits (breakers) for each outlet, 1440W is then available for each separate circuit
- run them off a 208V circuit; these can supply much more power (think 'electric range') and most PC PSU's can handle that voltage directly.

And, if you are living in the EU, you have a lot more power available to you out of a standard wall socket so this is less of an issue there.

BTW a 5850 does not pull 305W; that would be the pull of an entire PC including the 5850. A 5870 alone pulls about 200W. I have a PC with 2x5870; the whole thing pulls less than 500W from the wall (Kill-A-Watt meter), and that includes the PSU losses (90% efficiency). You can safely run 3 of these rigs (6 5870's) from a single 120V/15A (1440W) outlet.

Hope this helps.
 

[elrodvoss]

Thank you for all your input. 

The reason I ask, is I did not understand how they had these setups and were not blowing breakers, but they did not go into detail of the power needs.

But I have a unique situation, that due to my meter not working correctly and a lazy meter reader, I have not paid for Electric for over a year now.

The meter spins, but it does not change the meter numbers.  Of course, I can run whatever I want 24/7 and not be charged, yet.

Of course, i don't want to do anything that would require them to turn off the electric at the meter and rewire anything.  I would like to wire up some more circuits to the room directly above the breaker, so I can run multi-rigs.

All dreams and plans for now.  But it puts me in a position to make some nice rigs going.


Thanks in advance again.

-elrodvoss

[DeathAndTaxes]

The reason I ask, is I did not understand how they had these setups and were not blowing breakers, but they did not go into detail of the power needs.

You install an outlet like  this in your garage.   (or at least I am this weekend)



It is a locking L6-30R outlet (receptacle).  It allows you to pull 30A @ 240V w/ a plug like this:



30A @ 240V * 0.80 = 5760W. 

Also rigs don't pull as much as you think if you design them right, use high efficiency PSU, and run linux on USB stick.
My 3x 5970 rigs pull 870W at the wall.

5760W would be good for 5 4x5970 rigs or 40 GPUs.

[elrodvoss]

Also rigs don't pull as much as you think if you design them right, use high efficiency PSU, and run linux on USB stick.
My 3x 5970 rigs pull 870W at the wall.

Ya, I need to start to learn about linux when I get to multi-rigs.  So much that I never played and need to learn.  Since I need to slowly build, it will allow me to slowly learn as well and get it all right when I start to get to the big systems.

Thanks.

-elrodvoss

[tarrant_01]

I think my 2 6950's and 2 5770's were pulling 770 to 790W-ish @ 1.1G/h. I'm going to have to learn the linux stuff too. I'm thinking about building another rig and I'm a little concerned that it might be too much for my breaker as well.