I'm looking for someone that has a little more knowledge of the Battery Monitoring System than I do. When hooking up something such as a winch, is it better to:

1. Ground straight to the battery (traditional)
   1. Disable the BMS, or leave it be?
2. Ground to the BMS sensor at the battery (on the vehicle side, is this possible?)
3. Ground to the frame at the point of use (near the bumper)
4. Ground to the frame/chassis where the ground strap from the battery mounts.

 

You either need to disable the BMS, or the sensor needs to "see" all current flow. I would ground downstream of the sensor.

In my case, I am (will be) running dual batteries with an isolator, so I have no choice but to disable the BMS.

 

...

 

Thanks tmcolegr, looks like option number 4 wins.