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Yahoo Message Number: 111867

Unplug from shore power. VMS says batteries at 12.4. Have Auto Gen set to 12.2

The system automatically went to INVERTING. Nothing running inside except the empty fridge and two fantastic fans.

12.4 normal? New batteries by prev owner installed back in October. Guys down at Premiere in Junction City recently installed brand new 300 Inverter. They said all is wired up properly and looking great.

Should 12.4 be a concern? Just doing a dry run at the house before heading out for a dry weekend next weekend.

Re: Battery

Reply #1
Yahoo Message Number: 111868
Fully charged house batteries should be 12.7/12.8 volts when you unplug. I have one year old Lifeline AGM's and while boondocking earlier this spring, could  get thru the night fine with fridge running and HydroHot blowers running, with battery voltage about 12.4 when we get up. I usually started the generator then for 2 hours. It never got to 12.2 volt autostart. I found the A/V cabinet draws quite a bit of current, even when everything is turned off. Shut that down at circuit breaker, or if you have two inverters, shut off that inverter (fridge is on other inverter) if you are really having trouble getting thru night with decent voltage in the morning. If you are not starting with 12.7 volts when you unplug, you may have a bad battery/cell, and should probably have them load tested.


06 Magna 6642

Re: Battery

Reply #2
Yahoo Message Number: 111873

I would try turning the inverter OFF there at the VMS. I'd guess the voltage will be around .2-.3v higher with no load on the battery, which sounds about right to me. I know some folks leave the inverter on all the time, but in my mind unless you're running 120v loads that's an unnecessary drain on the battery. The inverter will draw a certain amount of current even at no load. Our battery shows no-load voltage around 12.6-12.7 after float charging.

Don Hutchins
Allure 470 31613

Re: Battery

Reply #3
Yahoo Message Number: 111881

Completely agree w/ Greg re: fully charged batt being 12.7 or 12.8. But that's with no load on them. With your inverter running, you have by definition got a load on the batteries and the voltage will be less. How much less depends on how much load. That's why I suggested shutting off the inverter. What is your "no load" voltage after fully charging? With relatively new batteries and no load, if it's not 12.7 you may have a battery problem, and should have them checked.

Don Hutchins

'08 Allure 470 #31613