10 amp breaker for 20 amp charger?

[Sundance]

I have a 1989, but I am looking at the 2004 Manual for wiring upgrade info, more specifically the 12V wiring diagram, it shows the 20 amp charger comming from a 10 amp breaker at the panel.  I am looking to revise my wiring to place a dedicated breaker for my 20 amp charger, but it seems to me I would want a 20 amp breaker.  It seems to me I could never "max out" my charger (good or bad) meaning I would trip the breaker at the panel, before I could get the full potential out of the charger.  Is this correct?  Any input would be helpful.

[Craig Illman]

It would be a lot less confusing if the chargers were rated in watts, instead of amps. 12v X 20A = 240 Watts.  Assuming maybe 70% efficiency, 240 Watts divided by 120 volts divided by .7 equals less than 3 amps. Your ten amp breaker should be fine. Check the specs for your charger on the manufacturer's website, if you don't have the manual aboard.

Craig

[Sundance]

Makes sence when you explain it that way.  Thanks.

[Ted Pounds]

Craig is right.  If you're asking about the AC breaker for power going to the charger 10 amp is perfect.  The output has it's owm internal fuse.