PSU's and Home Circuit Breakers

ShawnTX

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Kennesaw, GA, USA
I'm planning my first show for 2020 and have gotten pretty far into my setup and power requirements as I line up my purchasing plan for the year. I developed a Google spreadsheet breaking down my setup and power requirements HERE.

When I sort it out logically, I have 5 total PSU's powering the various parts of my show. These are a mix of 600W, 50A 12V and 300W, 60A, 5V. It occurred to me that the maximum Amps these power supplies would be using are 46.2, 42.12, 29.1, 30.48, and 26.52. That is the approximate draw at 100% white. The circuit breakers on my home range from 15A-20A. So any one of these PSU's would trip a breaker in my home if I were to go to 100% white. A couple of them would trip a circuit even if I went to 50%. Am I right about this? If so, what am I doing wrong in my planning? Should I be splitting this out across many more PSU's and circuits in my home? If so, I'm thinking I'm going to have a problem running all of those extension cords to the various plugs in my home just to get on different circuits. Any help educating me on this topic is greatly appreciated!
 

David_AVD

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Those current draw figures are on the low voltage side, so are not what the power supply draws on the mains (AC) side.

A 600W (DC side rating) PSU would draw 5 Amps from yorr 120V supply if it were 100% efficient.

The actually efficiency of power supplies is about 80% - 90% so that makes for a 750W power draw on the mains side worst case.

Dividing that 750W by the 120V mains voltage gives you 6.25 Amps. That's the current on the AC side.
 

ShawnTX

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So that 6.25 Amps is the max current on the AC side? Assuming I'm at 100% white (which I know I will never really need to do).

Does that mean that, if I were to run everything at 50%, that I would only be using 3.125 Amps of current on the AC side? Just trying to make sure that a drop in utilization on the DC side will directly correlate to a drop in utilization on the AC side (as a percentage).
 

David_AVD

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In general yes, the draw on the AC side is proportional to the draw on the DC side.

You need to get used to thinking in terms of power (Volts x Amps) when working out loads.
 

ShawnTX

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Dec 29, 2019
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Kennesaw, GA, USA
David,

Thank you for the replies. I was getting a little lost in the overload of information available on the web and that was the last little bit of info I needed to move forward. I have ordered power meters to get actual numbers on both sides of the equation (AC and DC side) so I will know my actual vs. estimates. I'll bench test everything before deploying, but this will definitely help in ordering the correct amount, and type, of equipment for my show.
 
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