I get your point that it could also be a battery issue.
Here's some evidence that has me convinced otherwise:
- The specific gravity of each cell in the four Trojan T-145s reads between 1.270 and 1.290. (measured when the converter is down to supplying less than 5 amps)
- The symptom existed since the RV was purchased new in 2016. Of course Camping World wouldn't do anything about it. Which is why I gave up and swapped out the stock batteries for the T-145s.
- A battery issue doesn't explain why there is a difference between the voltage measured at the battery and the Xantrex display voltage.
- The batteries all hold a charge. If I top them off, turn off the breaker to the converter and let the bank sit 24hrs, the SG doesn't change more than .005
What I noticed is that the residential fridge is turning on the frost-free heater a couple times per day. It's drawing 30 amps from the battery bank for 15min intervals. However when the fridge is just cooling, it is only drawing 8 amps. Thor says: the stock battery bank is designed to run the fridge for a weekend and no more. Yeah... I need more than that. Especially since the crappy, unreliable generator in the 2016 has always overheated and shutdown after about 45min - another thing Camping World can't seem to fix.
I'm going to do the calculations using the bank of T-145s. Now that I know the current draw and duty cycle, I should be able to determine the kWh required. Then, I'm going to load the bank with a similar draw (motor?) and eliminate the Xantrex and the fridge. Let's see how they perform..
Thanks for your input! Valuable info