Battery drain w fridge even on shore power

jeff57

I have a 2021 320 CSS and I am experiencing battery drain even when plugged into shore power.  I have a Battleborn battery and Victron BMV 712 battery monitor.  While driving with the fridge on we started the trip at 100% battery and after 7 hour drive arrived to campsite with 69% battery. Even with 4 hours shore power and only the fridge on we continue to have a 1.2 to 2.6 negative AMP and the battery went to 70% and now 69% and still around 13.22 voltage.
it seems like shore power is not causing a recharge of the battery.   I have the NuCamp standard converter.
Any suggestions are appreciated!
Thanks.   Jeff57

Sharon_is_SAM

The Norcold frig draws at least 4 amps when the compressor is cycling.  It is not as efficient as the Isotherms in the S model.

Do you have a charge wire with your 7 pin harness?

The converter will not completely charge a lithium battery.  I think you can get up to 85% recharge.  Solar will give you 100%.

This will help:  https://tab-rv.vanillacommunity.com/discussion/14208/lithium-battery-change-converter#latest

BlueYonder

Did you switch over from battery to shore power on the fridge?

Marceline

jeff57 said:

I have a 2021 320 CSS and I am experiencing battery drain even when plugged into shore power.  I have a Battleborn battery and Victron BMV 712 battery monitor.  While driving with the fridge on we started the trip at 100% battery and after 7 hour drive arrived to campsite with 69% battery. Even with 4 hours shore power and only the fridge on we continue to have a 1.2 to 2.6 negative AMP and the battery went to 70% and now 69% and still around 13.22 voltage.
it seems like shore power is not causing a recharge of the battery.   I have the NuCamp standard converter.
Any suggestions are appreciated!
Thanks.   Jeff57

Did you pre-chill the fridge from shorepower before you started your trip? If not, the fridge will consume a fair amount of power to get down to 40degrees and your alternator probably wouldn’t keep up. That would explain the initial drop. Do you hear your converter kicking on? You should hear the fan if its feeding power to the battery. 

BrianZ

If you wanted to get it more fully charged while on shore power, maybe you could isolate the battery & connect a charger with a lithium charging mode, like our Noco Genius 7200..