View Full Version : Battery Questions

11-02-2020, 12:59 PM
We just got our first camper, a Passport 267BH. Most questions I can find the answer on the web, but struggling to wrap my head around this one.

We also have an off grid cabin, and utilize a small DIY solar setup for LED lights, radio, etc. A $15 solar controller has enough functionality to shut off the load when the battery drops below 50%, and will switch to float mode when it gets to 100%.

Iím wondering how battery level is controlled in a camper? I believe the invertor keeps it from over charging when plugged in, but is there anything stopping you from dropping it below 50% when running off battery? Maybe even an add on device?


travelin texans
11-02-2020, 01:28 PM
FYI, unless you have a residential fridge you probably don't have an inverter (12 volt to 120 volt), you will have a converter (120 volt to 12 volt).
That converter when plugged into shore power will charge your batteries through different stages from trickle with no load to super duper with heavy load & supply 12 volt to the rv while charging. It will not disconnect power due to low battery charge when boondocking & I don't know if there's a way to accomplish that.

11-02-2020, 02:37 PM
Iím not sure if this would work but would a priority start or similar battery disconnect work? As a low cost answer? Iím not sure what it actually cuts off at but they are supposed to protect a car battery if you accidentally leave light or some accessory on. Otherwise my victron bmv712 has a warning alarm you can set to warn you of different states of charge.

11-02-2020, 04:20 PM
For an addon device, Victron offers a line of BatteryProtect devices that would do what you are asking. The caveat is the the electricity only flows through the device in one direction so you can not connect a load and a charger on the same device.