Watts consumed by 120vac to 12vdc charger-converter?

Thread Starter


Joined Jul 18, 2012
It has a transformer and is used in the boat to power and charge 12vdc items.
It has a 20 amp continuous rating and the meter can goto 30 amps output.

So how much AC power is this thing typically using if say outputting 10 amps dc power?

Here is it's schematic
Last edited:


Joined Nov 23, 2012
Is there a published efficiency rating. If not, assume 70% or so.
From there, 10 amp at 12V is 120 watts.

Efficiency correction, 120W out / 0.70 = 144 W in

144 W at 120 V = 1.4 amps in