12-06-2021, 12:35 PM
Brad,
good report!
I agree the Lithiums should run more than 48 hours with nothing running….So I would suggest the following…
1. Check the bay heaters (2 thermostats in the water bay) to see what they are set to. One controls the electric fan above the AH and the other is a fan fight above the water tank.
2. Check the inside electric heater (thermostat by the door). Make sure the AH is not running (At all). You should see LO on the AH temp display.
3. Make sure the BBs are fully charged at the remote control panel and double check that you have 13.7ish at the BBs.
4. Disconnect from shore power and start monitoring the voltage at the BBs every hour. See if you can see the voltage drop then extend the line until the cutoff voltage. This should tell you the actual discharge rate that the batteries are experiencing.
Side note: Lithiums are different from normal AGM and Lead acid batteries. Their discharge profile is very, very flat until you run out of juice and then it drops like a rock. At some point (not sure of how the BBs decide this) the BBs will simply cut off.
5. Verify that the Low voltage cutoff on the Magnum is set ABOVE the BB cutoff. (I bet BB will tell you the exact number they use).
This is an experiment that I never got done, but I suspect that you will find there is a current draw that is pulling batts down.
Good luck!
Bill
good report!
I agree the Lithiums should run more than 48 hours with nothing running….So I would suggest the following…
1. Check the bay heaters (2 thermostats in the water bay) to see what they are set to. One controls the electric fan above the AH and the other is a fan fight above the water tank.
2. Check the inside electric heater (thermostat by the door). Make sure the AH is not running (At all). You should see LO on the AH temp display.
3. Make sure the BBs are fully charged at the remote control panel and double check that you have 13.7ish at the BBs.
4. Disconnect from shore power and start monitoring the voltage at the BBs every hour. See if you can see the voltage drop then extend the line until the cutoff voltage. This should tell you the actual discharge rate that the batteries are experiencing.
Side note: Lithiums are different from normal AGM and Lead acid batteries. Their discharge profile is very, very flat until you run out of juice and then it drops like a rock. At some point (not sure of how the BBs decide this) the BBs will simply cut off.
5. Verify that the Low voltage cutoff on the Magnum is set ABOVE the BB cutoff. (I bet BB will tell you the exact number they use).
This is an experiment that I never got done, but I suspect that you will find there is a current draw that is pulling batts down.
Good luck!
Bill
Bill Johnson
Birmingham, Alabama