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Topic: Shore Power and House Battery Charging (Read 141 times) previous topic - next topic

Shore Power and House Battery Charging

I have not dealt much with these issues, and need some guidance.

We temporarily relocated our coach to a friend's front yard while we had some paving done.  While there, the generator auto switch started the generator to charge the house batteries.  I did not know the button was pressed - may have been that way for ages.

It SEEMS like the house batteries did not accept a good charge, but that is secondary.

When plugged into shore power, I get no AC in the coach.  I checked and cycled all of the breakers.  Inverter charging is off.  When I run the generator, I get AC, and the inverter starts charging the house batteries.  A few years ago, I replaced both transfer switches with PD52s.

1.  I cannot think of a reason that low house batteries (11.6 volts) would prevent the transfer switch from operating.

2.  I THINK one transfer switch is for allowing shore power, and the second is for prioritizing shore over generator.  Correct?

3.  I THINK there is an AC wire that signals the transfer switch to operate.  Is there anything between the big AC input on the transfer switch, and the wire that triggers?  Any separate breaker or circuitry?

4.  Should manually pressing the contactors in the transfer switch make the power transfer (assuming the contactor is not burned up?)

I will be digging for some paper manuals, and I would welcome your guidance.
Matt B
1998 u-320

Re: Shore Power and House Battery Charging

Reply #1 –
Looks like I found the problem!

My "hold against" AC tester showed power at the inlet of the transfer switch.  But it was only the hot, and not the neutral.  A little adapter was the problem.  Things electrical seem OK now, and I will see if the house batteries charge properly.
Matt B
1998 u-320

Re: Shore Power and House Battery Charging

Reply #2 –
I am sure someone more familiar will chime in but I believe one transfer switch is for the inverter and the other to switch between shore and generator. Priority is determined by how the transfer switch is wired.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Shore Power and House Battery Charging

Reply #3 –
Quote from: oldmattb –
2.  I THINK one transfer switch is for allowing shore power, and the second is for prioritizing shore over generator.  Correct?
Actually, like Chuck (craneman) says, one transfer switch selects between shore power or generator power.  The other one controls the inverter/charger.

See typical 110V power schematic linked below:

https://www.foreforums.com/index.php?media/item/a-2700-07-2000-u270-295-320-110v-elect-relay-syste.5273/
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Shore Power and House Battery Charging

Reply #4 –
Yes!  That makes sense.  Thanks!
Matt B
1998 u-320