Battery cut off switch

[GME2279]

Could someone tell me why you would put a cut off switch on your camper's battery? How do you do it.

[TURBS]

If you don't put in a battery disconnect when not in use and not plugged into shore power the battery will go dead from phantom draws.



2015 Columbus 320RS
2008 2500HD Duramax
2015 nights camped "34"
2016 nights camped "10"

[JustB_Rad]

Originally Posted by GME2279

Could someone tell me why you would put a cut off switch on your camper's battery? How do you do it.

I just put mine on last night because over the course of the campers first year, the constant draw from the CO2 detector and radio seems to have killed the battery to the point my awning won't retract without the motor cycling. Replaced the battery, awing comes in fine.

I mounted the switch to the side of my battery box. You will also need to purchase a short battery lead to get from the battery to the switch, then the camper lead hooks up to the other side of the switch.

This is what I used. The knob is removable as https://www.amazon.com/Marinco-701-B...=1&*entries*=0

[Skyliner]

The camper has items that constantly draw power from the batteries. Most single battery campers will go dead in about 3 days and once a battery is fully discharged, it will have permanent damage which is evidenced by reduced capacity.

Having a battery selector switch is an easy way to disconnect the battery without pulling the lug terminal off of the battery each time you want to connect or disconnect.

How to do it:
Buy cable, cut to size for location of switch, crimp or solder connector to battery cable, attach to switch and your are done. Run wire from + terminal to switch.

My fifth wheel has 3 battery banks and each one is switched.

Recommend you use a Blue Sea Systems switch which are easy to rotate and well made. Perko are good switches but wife has trouble rotating them.

https://www.youtube.com/watch?v=B4830QsybbM

[Auscon]

Originally Posted by TonyD

Run wire from + terminal to switch.

I have read that some people put it on the - terminal and some put it on the + terminal. Which one should it be put on?

[DAISY BOYKIN]

By all means the + (positive) terminal.

[NMWildcat]

I always just put a on/off switch on the negative cable. Easy and you don't have to buy extra cable.

[Stormrider151]

Originally Posted by Auscon

I have read that some people put it on the - terminal and some put it on the + terminal. Which one should it be put on?

I put mine on the negative terminal. It shuts off everything including my power jack. I can't hook up without the switch being on. To me it's much safer that way. No chance of forgetting to turn it on before pulling out.

[stansoper]

This is from a previous post of mine. See attached. Would not be without one.

[TGR]

My trailer came with a power disconnect switch on the positive terminal that serves me well. It doesn’t disconnect my slide out motors, landing gear nor rear stabilizer but it does turn off all my parasitic draws. If I were to add a battery cutoff switch, I would put it on the negative side of the battery for the same reasons you should disconnect the negative battery post first when removing a battery.


A wrench or tool accidently touching the negative terminal to ground on an installed battery has no effect. After first disconnecting the negative terminal of the battery, shorting the positive terminal to grounded trailer parts with your wrench also has no effect either because the negative terminal is open. On the other hand, accidentally shorting the tool to ground, while disconnecting the positive battery terminal first, can cause a large spark.


This may not be a major concern but it is the reason many advocate putting the battery disconnect switch on the negative terminal instead of the positive one. In either case, the battery is electrically disconnected from the trailer.

[camaraderie]

Originally Posted by TGR

My trailer came with a power disconnect switch on the positive terminal that serves me well. It doesn’t disconnect my slide out motors, landing gear nor rear stabilizer but it does turn off all my parasitic draws. If I were to add a battery cutoff switch, I would put it on the negative side of the battery for the same reasons you should disconnect the negative battery post first when removing a battery.


A wrench or tool accidently touching the negative terminal to ground on an installed battery has no effect. After first disconnecting the negative terminal of the battery, shorting the positive terminal to grounded trailer parts with your wrench also has no effect either because the negative terminal is open. On the other hand, accidentally shorting the tool to ground, while disconnecting the positive battery terminal first, can cause a large spark.


This may not be a major concern but it is the reason many advocate putting the battery disconnect switch on the negative terminal instead of the positive one. In either case, the battery is electrically disconnected from the trailer.

I'd also note that the SIZE of the positive and negative terminals is slightly different and the popular TERMINAL mount disconnects (see below) are sized for the NEGATIVE terminal and you can damage the battery by pounding it on the positive post.

[GME2279]

Thank you so much for your knowledge, and advice. I ordered the switch, and extra lead wires already. Now my husband and I will get it done right

[KDHfan]

Check out YouTube... There are a few vids on adding one. I recently added one to mine and it was much easier than I anticipated. I used the negative terminal.

[jughrad]

The following is a link to to a video of how I installed my battery cutoff switch. I am not saying it is the best installation but I think you may find some value in the information. This method has been working great for me.

https://www.youtube.com/watch?v=nmtRpARGMc8

[jughrad]

Originally Posted by Auscon

I have read that some people put it on the - terminal and some put it on the + terminal. Which one should it be put on?

NEGATIVE!

Less chance to short to the frame. If you are working with the positive cable you can easily find a place to short it out. The confusion comes from marine installations where you use the positive wire. Otherwise there is electrically no difference whether it is in the positive or negative leg.

[tomrob1161]

My coach battery disconnect switch, 2013 Rockwood 8315 BSS, shuts down my co2 & propane detectors and my radio. I do not have electric where I currently store my trailer and still after 3 -4 weeks, I have 3/4 charge on my battery. When I push the disconnect switch the co2/propane detector light goes off as well as the radio light.