Battery Disconnect positive or negative side?

[SFVdave]

My battery disconnect on the positive side only kills the light, fridge and furnace. Still have lots of parasitic drain, probably from 1 or both of the 2 other positive battery cables. Can I add a battery cut off switch to the negative side and kill everything or is that not recommended with certain components like levelers and slideouts?

[SFVdave]

Here's my battery compartment. Originally, all 4 red cables were on one post. I added the adapter so I could attach the positive for solar and battery monitor from shunt.

[pianotuna]

I'm a buss man myself. (and balanced, too!)

[MEXICOWANDERER]

Flooded batteries corrode anything connected to either post.

Connect lots and lots of wire and cables to the two posts

Have lots and lots of corrosion.

Connect one, single cable to battery post and run cable to multiple connect buss bar.

A fraction of the problems

Now which method appeals to you?

[time2roll]

Do you have more than one positive wire coming off the battery?
afaik there should be one wire that goes to the cut-off switch.

If there are other wires I would discover what they are connected to and verify no current flow.

Next is the switch. Again need to discover what is connected to the battery side and what power does it use.

I would tend to rewire and adjust so that the OEM switch does as you expect. Or why have it at all.

[Boon_Docker]

SFVdave wrote:
Would something like this work?
Inline circuit breaker
I could cut the cable at the battery and insert this.

That is what I use for a disconnect, works fine. I use a 150 amp.

[MEXICOWANDERER]

LIFT the negative battery cable from the negative post/

ALL LIGHTS GO OUT
Batteries are wired correctly

ALL LIGHTS DO not GO OUT
Are there wires running to the other 12 volt battery negative? WIRED WRONG

[RJsfishin]

Quote:
Some things really need power all the time
----------------------------------------------
Oh no they don't either,....and especially not any memory held items !!! DUH??
The reason for a batt cutoff, is to illuminate any possibility of the batteries being drained. Have to wonder what ever gave you that idea.
And I don't care whats common, or what the factory does, or anything else. I just know whats right.

Oh, to answer the question,...whichever cuts the entire 12v circuit, bar nothing.

[CA_Traveler]

Won't work - it must handle the maximum amps, consider inverter or emergency start, etc. Consider something like this switch:

[SFVdave]

Would something like this work?
Inline circuit breaker
I could cut the cable at the battery and insert this.

[wa8yxm]

Some things really need power all the time.. Steps if they are automatic need to extend when door is opened... Explosive Gas, Smoke and CO detectors,, Really should never be disabled.

But yes. you can add a 2nd switch if you wish and kill EVERYTHING.

Depending on where the switch is.. You may also be able to move the positive leads to the switched terminal instead of the battery.

[SFVdave]

CA Traveler wrote:
Yes.

It may be wired as intended by the mfg. It's common for the salesman switch to not disconnect everything. And my manual disconnect switches also don't disconnect everything on either battery bank.

I did install a disconnect switch on the house battery negative terminal and will probably do the same on the chassis batteries.

It's a Class C MH so no 5er or TT issues.
The battery system has the BIM Battery Isolation Manager on a separate fuse and relay panel. This BIM monitors both house and engine batteries and charges both or either when needed (Bi-directional). So it's always powered. It's wired correctly. I either have to add a cutoff for that cable (also has generator, awning, levelers and more on it) or all the negative.

[Bobbo]

"Danger Will Robinson!"

If your RV is a trailer or 5er, disconnecting the negative also disconnects the breakaway brakes. Not recommended. If you forget to reconnect the negative to the battery and tow, there is no emergency braking.

If your RV is motorized, disregard this post.

[CA_Traveler]

Yes.

It may be wired as intended by the mfg. It's common for the salesman switch to not disconnect everything. And my manual disconnect switches also don't disconnect everything on either battery bank.

I did install a disconnect switch on the house battery negative terminal and will probably do the same on the chassis batteries.

[YC_1]

It is not uncommon to leave things like steps connected. Or to keep radios programmed. Disconnecting the negative is just fine.