Power supply input vs output current

Keitho

Enlightened
Joined
Jun 7, 2017
Messages
781
Location
CO, USA
Basic question...If I hook up a couple of AC-DC power supplies to a circuit in my home, I want to be sure I don't throw the circuit breaker at the panel (120V AC, 20 Amp max). My power supplies are rated at a max of 14.6 Amps at 24 Volts. Does that mean that, if I'm using about 80% of the full current for each power supply, I might be using close to 14 Amps out of my 20 Amp max, or do I have to do some math to convert the 24V 14.6 Amp output current into 120V AC current draw?

Thanks!
 

Lampas

Newly Enlightened
Joined
May 14, 2013
Messages
20
120v * 20a = 2400 watt. but i wouldn't recommend going near that, you always need some headroom! if one power supply can deliver 14,6a at 24v thats 350 watt output, if the efficiency is around 80% it will draw theoretically around 420 watt, although it can be way more under certain conditions. for example when switching on, hight peaks can occur.


So adding some power supplies should be fine, but I'm no expert and these things a usually more complicated then one would think.
 

beatus

Newly Enlightened
Joined
Dec 2, 2017
Messages
7
Basic question...If I hook up a couple of AC-DC power supplies to a circuit in my home, I want to be sure I don't throw the circuit breaker at the panel (120V AC, 20 Amp max). My power supplies are rated at a max of 14.6 Amps at 24 Volts. Does that mean that, if I'm using about 80% of the full current for each power supply, I might be using close to 14 Amps out of my 20 Amp max, or do I have to do some math to convert the 24V 14.6 Amp output current into 120V AC current draw?

Thanks!

your power supply power = 24V x 14.6A = 350.4Watt, normally a AC-DCpower supply has 90% inverting rate, then your acutal power consoumtion of each power supply is: 350/0.9=388Watt.

Your panel total power: 120V x 20A = 2400Watt, and using 80% of your panel is 2400*0.8=1920Watt

1920Watt/388Watt= 4.95,

Means you can use 5 of this power supply for your panel!
 
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