Prevent AGM batteries from dipping below 50%

[jgbagley]

I just purchased a 2019 FC 26' which comes with AGM batteries and a SeeLevel Monitor panel to show you the levels of your batteries. From what I read, it is important that you do not discharge your batteries below 50% or you could damage them. I was wondering if there was any suggestions about how to prevent it from dipping below 50% other than just frequently monitoring that panel? Seems like it would get tedious to constantly be checking back to make sure you were not below 50%.

[Peter C]

Yes it can degrade the batteries if they drop below 50%. If you are only using your lights, pump, and fridge (on propane) you should be fine to only check a few times per day. If you are running things on the inverter then it is going to drain them much faster and You should check after using the inverter. You can save a bit of power by only turning on your water pump when you need it.


There is really no easy answer. Once you get a feel for it you will know when things should be getting low and check more frequently. I have a CPAP so I check my battery levels regularly to make sure I have more than enough to make it through the night.

[jeffmc306]

jgbagley, the more reliable way to tell how discharged your batteries are is by installing a Victron battery monitor. This works like a fuel level gauge on your tow vehicle.

As your batteries discharge, a shunt connected between your batteries and the load of your trailer measures the current used. When you recharge with either shore power or solar, the shunt measures the current going back into the batteries. This is the more accurate way to tell when you’ve consumed 50% of your batteries.

Victron now sells a SmartShunt without the display. You can monitor everything via their App using Bluetooth.

I installed a BVM-712 with the display but would have gotten the SmartShunt if it was available at the time. I never look at the display.

I documented the installation on this thread (hot link). Good luck!
Jeff

[jgbagley]

Thanks for all the info. I was thinking there would be an automated way to disconnect the battery at 50%, but think I'll just keep a close eye on it.

[JEB]

Originally Posted by jgbagley

Thanks for all the info. I was thinking there would be an automated way to disconnect the battery at 50%, but think I'll just keep a close eye on it.

The Victron products mentioned above can be programmed to trigger an alarm when the batteries discharge to whatever level you select. Although not an automatic cut-off, it's close