Community Forums

JF1957 · 03-23-2020, 01:14 PM

On my class c motorhome i recently notice that my generator doesn’t charge my home battery, any tought ?

Skip426 · 03-23-2020, 01:24 PM

The motor home gen set should power the same charge system for the house batteries that shore power does , so you need to check the operation of your converter/charger ( or inverter/charger if so equipped ) when the RV is plugged in to shore power.
Note that many motor homes do not have a system to charge the chassis ( engine start ) battery. Owners have to add one.

twinboat · 03-23-2020, 02:47 PM

Does the generator power anything, like the AC or microwave ?

If not, check the circuit breakers out on the generator.

JF1957 · 03-23-2020, 02:50 PM

Quote:

Originally Posted by twinboat

Does the generator power anything, like the AC or microwave ?.

Yes

okcnewbie · 03-23-2020, 02:55 PM

Do you know what model converter or inverter/charger you have?

Are you positive you charge correctly when plugged into shore power?

twinboat · 03-23-2020, 03:45 PM

Quote:

Originally Posted by JF1957

Yes

Does it charge on shore power ?

If you haven't and can't try it on shore power, check for a tripped GFCI outlet.

Some converter/chargers are plugged in to GFCI protected circuits.

JF1957 · 03-24-2020, 06:37 AM

Quote:

Originally Posted by twinboat

Does it charge on shore power ?

If you haven't and can't try it on shore power, check for a tripped GFCI outlet.

Some converter/chargers are plugged in to GFCI protected circuits.

Yes it charge on shore power and was charging with the gen before a week ago

John Hilley · 03-24-2020, 12:00 PM

Check the breakers on the generator

JF1957 · 03-25-2020, 06:52 AM

When the gen is running everything work fine 12v, 120v but the battery doesn’t charge.

twinboat · 03-25-2020, 07:56 AM

The generator output is a substitute to shore power.

Both shore and generator power go to a transfer switch. The switch decides which 120 volt power goes to the main breaker panel.

The main breaker panel distributes that 120 volt power to all breakers, including your battery charger.

Having said that, the only way you can have this issue is if someone rewired some circuits, but you say it worked last week.

How are you determining that the batteries are not charging on generator ?

While on generator, are you shutting off the battery disconnect switch near the door ?

US1 · 03-25-2020, 10:20 PM

This is a stumper.
I guess my 1st question would be, are you 100% positive you are checking the house battery and not the chassis battery?

JF1957 · 03-26-2020, 07:37 AM

Quote:

Originally Posted by twinboat

The generator output is a substitute to shore power.

Both shore and generator power go to a transfer switch. The switch decides which 120 volt power goes to the main breaker panel.

The main breaker panel distributes that 120 volt power to all breakers, including your battery charger.

Having said that, the only way you can have this issue is if someone rewired some circuits, but you say it worked last week.

How are you determining that the batteries are not charging on generator ?

While on generator, are you shutting off the battery disconnect switch near the door ?

I have install a multimeter from the house battery that give me the voltage, watts, and amps results. I also got an 1000 watts pure sine inverter. Now let me explain what happen while i was on my way back home from Florida last week. We where sleeping on a Wally near Albany, before going to sleep i shut off the inverter, from now the battery was at about 13.03v. By 5:00 in the morning weather was near 50 degrees in the MH (we love to sleep in the cold) so i decided to start the furnace, after about an hour of full running heater i go take a look to my battery voltage, they where dropping at 11.87v. I don’t like seing my battery below the 12v mark so i decided to start the generator, at that point i didn’t look at the multimeter because knowing my system i was sure that the battery was charging. When i weak up at about 7 o’clock my battery voltage was at 10.8v with the gen always running so i decided to start the MH an from there battery begins to charge. I didn’t have time to look at my issue from now.

twinboat · 03-26-2020, 07:55 AM

To continue the story, did you get home or a CG and plug in to shore power and the house battery started charging ?

If you haven't made that step yet, it may be a house battery charging problem. Your converter/charger.

In almost all motorhomes, when you start the engine, the engine alternator charges the chassis and house batteries, so what you experienced is normal, but it is not part of the house charging system.