Ever since we purchased our new camper (two years ago) I have consistently had to use a battery charger prior to each trip to recharge the dead battery. While I am not exactly sure what keeps draining the battery, I have my suspicions that the CO detector is the culprit.
This year I had to purchase a new Deep Cycle Marine/RV battery for the camper and after only a week the battery was dead again. While deep cycle batteries are designed to handle this type of abuse, repeatedly draining a battery will shorten its life span. So, I decided to install a camper battery disconnect switch. This was an easy install that only took about 30 minutes and should help to extend the life of our camper battery (as well as save me from having to recharge the battery on a regular basis).
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Items needed for install:
- Marnico 701 Battery Disconnect Switch
- 24″ 4 Gauge Switch-to-Starter battery cable
- Drill and metal drill bit
- Screws or bolts depending upon your mounting configuration (these are not included with the disconnect switch)
Step 1: I disconnected the battery and set it aside.
Step 2: Determine where you want your switch to be located and mark where to drill the four holes. A few tips:
- Make sure that both the positive terminal of your camper AND the switch-to-starter cable will reach this location.
- Try to install it in a location that is somewhat protected from the elements. While the switch is weatherproof, I mounted it to the frame of the camper behind the battery box.
Step 2: Pre-drill holes that are the right size for the screws or bolts that you plan to use. I was using screws so I drilled holes that were slightly smaller than the screws I was using.
Step 3: Connect your camper’s positive* battery cable to one of the battery disconnect switch posts and the switch-to-starter cable to the other post. (My power jack also has its own positive wire that I attached to the same post as the camper positive.)
*See discussion below in the comments about the pros and cons of using the positive versus negative terminal. Before installation, always check with the manufacturer about proper placement of the cables for your unit.
Step 4: Use the screws or bolts to attach the rear plate and switch to the camper.
Step 5: Put the battery back into the proper location and connect the switch-to-starter cable to the positive battery terminal and your camper’s negative wire to the battery’s negative terminal.
You can now test your connections, but you should be good to go!
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Thank you! Had the same issues and wasn’t quite sure when to use the disconnect red switch. Had the same exact problem here too – I do bet the CO2 detector is it! Good post. Jason
Hi Jason–Thanks so much for stopping by and reading! Glad the post was helpful! 🙂 Happy camping!
Hello, great information..I have looked all over the Internet and YouTube and you have the easiest most detailed info out there..thanks. Please confirm that it is the positive cable going to the switch and then to the trailer? Also, does it matter what post is used inside the switch (instructions for my switch does not say)Thanks again,
Chad,
Thanks for stopping by! We are so glad that the article and video was helpful to you. To answer your questions: For our application, yes the positive terminal of the battery was connected to the disconnect switch and then the camper positive was also connected to the other pole. This essentially adds a on/off switch to the positive line going from the battery to the camper, so when turned to “off” the camper devices do not continue to draw from the battery. Regarding which post to use inside, for our switch and application it did not matter. But we would encourage you to check with your camper manufacturer or local dealer to ensure your camper configuration will work in the way ours did.
You indicated that the switch was hooked to the positive side of the battery. I have hooked the switch to the negative post and then grounded the other side of the switch to the body of the camper; it seems to work but now I am wondering what the implications are to the battery
Hi Wayne–thanks so much for stopping by! We’ve been out of town for the holiday and getting caught up on messages. To answer your question we did a little research. For our camper, installing the disconnect switch worked on the positive side, but others prefer to place it on the negative. Here’s an in-depth answer from RVTravel.com: https://www.rvtravel.com/rv-electricity-12-volt-tech-battery-disconnect/
Mark Polk also prefers to place it on the negative side: https://www.youtube.com/watch?time_continue=4&v=XxddcFI5QQI&feature=emb_logo
But others prefer the positive side: This Heartland RV schematic shows it on the positive side: http://manuals.heartlandowners.org/Electrical/DC_Buss_Bar/Heartland/Buss_Bar_for_LM-BH-BC.pdf. Since there’s enough debate about it and since every camper may have a slightly different setup, we would encourage you to check with your camper manufacturer or local dealer to ensure it is wired properly.
All the best!
It does not matter which side you use, you are accomplishing the same thing. The advantage of connecting to the Negative Terminal, cable is you reduce the chance of an eletrical spark.As your battery is charged it may exhaust some Hydrogen fumes. Remember the Hindenburg? KABOOM, one spark and it was all over. The ground cable terminal usually prevents that from happening. Also try to mount the switch awauy from the battery. When working with batteries, always, always, always DISCONNECT the ground, NEGATIVE cable first. Then you will have less chance of a spark. If you are charging the battery, always, always,always,always unplug the AC power cord on the battery charger first. If you leave it plugged into the AC, and remove the clamp, you will create a spark and KABOOM !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1
Why do you have a carbon dioxide detector?
Hi Dell! Thank you for pointing out a typo! 🙂 It should have just said CO, for carbon monoxide detector. Thanks so much!
I really like this Ampper Am-CBS01 Battery Switch because it’s small and cheap. It has a simple and compact design that packs enough features to eliminate unnecessary power draw in my vehicle. The switch has a very solid feel, it’s easy to know if it’s switch on or off. The device works with 12-volt systems as it does with 48-volt battery systems. Securing your vehicle’s electrical system should never be a problem with this product.