Battery charging dilemma

[Stephen Quandt]

I am having problems with battery charging either on shore power or generator,
have none. Off the alternators no problem all batteries are charged with
adequate voltage. I can operate all other electrical devices on either
generator or shore power. I have 120 volts to the outlet that the chargers plug
into so not a circuit breaker issue. Before I go further with replacing the
chargers (look like they are original) is there a fuse between the chargers and
batteries that I might be missing?

If I have to replace I am open to suggestions from those who have done this
before.

Thanks
Steve Quandt
93-PT40
Iron Mountain, MI