View Single Post
Old 02-03-2021, 07:25 AM   #21
MarkEHansen
Senior Member
 
MarkEHansen's Avatar
 
Join Date: Oct 2018
Location: Sacramento
Posts: 1,005
Quote:
Originally Posted by apachewolf View Post
I always use a master disconnect on the NEGATIVE side, that way all power is disconnected, no guessing about "phantom" loads draining the battery when you think it is disconnected. In car service you always disconnect the negative first to ensure total disconnect.

Happy camping.
That is not why you disconnect the negative cable first. You disconnect the negative cable first because disconnecting the positive cable first runs the risk of shorting your wrench to ground.

As for a battery disconnect, disconnecting either the negative or positive makes absolutely no difference. Once the circuit is interrupted, no current will flow.

The reason why there are phantom loads in RVs even when the battery disconnect is off is due to those loads being attached to the battery before the disconnect - as they need power all the time (and should not be "disconnected").
__________________
2022 Cedar Creek Champagne 38EL - "Big Bertha"
2019 GMC Sierra 3500 Denali HD 6.6L Duramax TD, CC, 4WD, DRW - "Mr. Beefy"
MarkEHansen is offline   Reply With Quote