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What is an RV Battery Disconnect Switch & Do You Need One?

If you’ve seen or heard of an RV battery disconnect switch before, you might have asked yourself: why would I need one?

RV battery disconnect switches are used to disconnect your batteries from your electrical system and may be useful to have when storing your RV or electrical work. You might also use one if you have an old converter or an external battery charger. 

So how do RV battery disconnect switches work? And what are all the reasons to have one? Let’s take a look.

What’s an RV Battery Disconnect Switch?

A battery disconnect switch on the armrest of a vehicle
An RV battery disconnect.

An RV battery disconnect switch does exactly what it says on the tin: it disconnects your battery. 

As you might already know, your RV has two electrical systems: AC and DC. Your AC electrical system is powered by shore power or via battery using an inverter. Your DC system takes power directly from your batteries. 

How Does a Battery Disconnect Work?

The battery disconnect on an RV separates your battery from your electrical system. It works like any other electrical switch, such as a light switch. 

Usually, wires are attached to two metal lugs on the back of the switch. When the switch is in the off/closed position, electricity flows through it as normal. But when you switch it to on/open, the circuit is broken and electricity stops flowing. 

Some RV battery disconnect switches also go directly on the battery terminal. Typically, these work using a metal “blade” that can be lowered and raised. When it’s lowered, it makes contact with another metal part, allowing the current to flow.

Do You Need an RV Battery Disconnect Switch?

So why have an RV battery disconnect switch? There are a few different reasons.

When Your RV Isn’t in Use

The main use of an RV battery disconnect switch is when you’re putting your RV in storage or otherwise not using it for a while. 

Even when you aren’t using them, any electronics attached to your batteries will draw a small amount of power. If your electronics stay connected and you don’t charge the batteries, they’ll eventually discharge completely and potentially be damaged. 

Using an RV battery disconnect switch prevents your battery from rapidly discharging when not in use. This is especially useful for part-timers and weekend warriors, whose RVs can go weeks or even months without use. 

When Boondocking

In a similar vein, a battery disconnect on your RV can also help you conserve power while boondocking. Without the extra drain on your battery, you’ll be able to stay out longer without running out of power. 

However, it’s important to keep in mind that, even when disconnected, your battery will still discharge. Disconnecting it will greatly slow down this discharge, but not stop it completely.

When Using an External Battery Charger

Another reason is that you want to use an external battery charger, rather than your built-in converter/charger. These smart battery chargers can charge your batteries much quicker than your converter/charger can. 

Safety

Lastly, you may want to use a disconnect for safety when doing electrical maintenance. An RV battery disconnect switch will keep you safe from shocks and other hazards. 

How to Install an RV Battery Disconnect Switch

A gloved hand disconnecting an automotive battery wire from its terminal
The first step to installing an RV battery switch is disconnecting your batteries.

Installing an RV battery disconnect switch is fairly simple and you won’t need an electrician’s license to figure it out. That said, always read any manuals, instructions, or RV disconnect switch wiring diagrams that may be included. And if you’re still feeling uncertain, it never hurts to enlist the help of a professional. 

Before you start installing, there are a few things to get together. 

  • First, unless your switch goes directly on the battery, you’ll need some extra cables to connect your disconnect switch. As a general rule of thumb, you should try to match the wire gauge to your existing cables. 
  • You’ll also want a socket wrench or other tool to tighten the lugs on your disconnect switch. Depending on how you mount your switch, you may also need a drill to make holes for mounting hardware. 
  • One final thing for clarity: when the switch is “on/open”, this refers to the state where no electricity is flowing. When it’s “off/closed”, this is when electricity is flowing. So, if the switch is on, the electricity is off, and vice versa. 

With no further ado, let’s look at how to install a battery disconnect switch.

1. Disconnect Your Battery

Before doing anything else, disconnect your battery, otherwise, you put yourself at risk of electric shock.

Always remove the black negative wire from its post first, then the positive wire. The negative side is grounded to your RV’s frame, so there’s no chance of sparks. But if you disconnect the positive side first, you’ll be at risk of sparking. 

This is also a good opportunity to clean your battery terminals. If you have a lead-acid battery that requires it, it’s also a good chance to check fluid levels and top off if necessary. 

2. Connect Your RV Battery Disconnect Switch to the RV

With the battery disconnected, you can now connect the RV battery switch. When installing the switch, make 100% sure it stays in the on/open position at all times. 

Generally, it’s recommended to install the switch on the negative side of the battery. However, using the positive side will still work. For this guide, we’ll install on the negative side, but the process is otherwise the same. 

Run your negative (black) wire from the RV side to one of the lugs on your switch. Use your socket wrench to tighten it. 

Next, connect the wire for the battery side to the switch the same as the other wire. However, do not connect this wire to the battery just yet. 

If your switch mounts directly to the battery post, simply place it on the negative terminal. Again, ensure the switch is open. Then tighten it in place and skip straight to step 4. 

3. Mount your RV Battery Disconnect Switch

Before getting everything connected and the energy flowing, you should mount your switch in place. It’s recommended to plan this out before you begin the install process, and if you need to drill, do that beforehand as well. 

If your battery has an external box or lid (not the lid where the battery posts are, but one on top of that), this is a popular place to install the disconnect switch. You can also install it on the wall in your RV somewhere, such as in the battery compartment. 

Mounting can be done with hardware, and the switch will often include some for you to use. If the mounting surface is smooth, you can also use heavy-duty double-sided tape or command strips.

4. Complete the Circuit and Test it Out

Once everything is in place, you can complete your circuit and test that everything works correctly. 

Ensuring the RV battery switch is still in the on/open position, connect the positive wire to the positive post. Then reattach the negative wire to the negative post. 

Now, you can switch to off/closed and engage your batteries. If everything is connected properly, your lights and other 12 volt electronics should now work properly.

An RV Battery Disconnect Switch is a Handy Tool to Have

With an RV battery disconnect switch, you have an easy way to disconnect your RV batteries anytime you need to. 

Installing an RV battery disconnect switch is easy and just requires attaching a few wires and mounting the switch. Once it’s installed, all you have to do is flick the switch and boom! Your batteries are disconnected. 

Do you have a battery disconnect on your RV? Do you need one? Share below in the comments.

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27 thoughts on “What is an RV Battery Disconnect Switch & Do You Need One?”

  1. I have a factory disconnect switch. If off, can I connect a separate trickle charger to keep the batteries at full charge? Can I do so without disconnecting any battery wires?

  2. Great device but keep in mind, there may still be a parasitic drain from things like your infotainment system or your propane detector. So in addition to the battery disconnect, I also disconnect the negative terminal on the batteries to complete the disconnect.

  3. Any RV with a “Use/Store” rocker switch already has battery disconnect, except that it is more conveniently operated. It works by opening and closing a bi-stable relay.
    You will want to test this out to see if it is a 100% disconnect. Some coaches are wired so that the smoke detector and carbon monoxide detectors remain on, regardless of the position of that switch/relay. This is a good idea when the coach is occupied, but not when the coach is in storage.

  4. Question: I have a solar panel that charges my battery mounted on the roof of my 5th wheel. Do I need to use the battery disconnect while stored and the panel is exposed to sunlight charging the battery?

  5. I’d say the style that hooks directly to the battery is the way to go. My motorhome has a factory installed “disconnect switch” on the panel. Flip the switch and nothing works inside. Leave it set for 12 weeks and the batteries are dead. Something wrong with that picture !

  6. Hello Charles Loneoutdoorsman here
    This note refers to your “battery disconnect switch” YouTube presentation.
    Ey have been traveling on the road full-time for the past 8 years in my Arctic Fox 990 and have owned RV’s of some kind for the past 50 years. (Ey am 81 years of age and still traveling).
    Camper Smarts presentations in general are very informative and your Battery Disconnect feature is especially well presented and thorough.
    Thank you

  7. I had a dead battery on my camper, but it didn’t seem to matter because we were on shore power

    I bought a new battery when we moved, and the next day I had an issue with my tow vehicle, a 250 amp fuse had blown!

    The only thing I could think that was any different was the new battery, so after that I always disconnected the battery when towing.

    Maybe that wasn’t the issue, but I never had any problems after that

  8. I’ve wanted one of these for a while. I’ve shopped a lot of them that look like the ones with the green or blue ring knob in the images up top. I haven’t bought any because the reviews about their failure modes have been so lousy. Knob failures where the switch is always off or on, some come apart when used, some work fine for a few weeks and then never again. Most are made by no-name outfits in China; one I found advertised as “100% American made workmanship” that cost twice as much as the others described their guarantee as “the product is free from defects in materials and workmanship at the time of shipment,” which is no guarantee at all. Curiously, this is one of the few “RV newsletter” articles of this type I have ever seen that DOESN’T contain affiliate links to recommended products. I could sure use some recommendations to higher-quality models.

  9. On a switch, ON or I (in) = The circuit or contacts are Closed (touching), allowing current to flow.
    OFF or O (out or open) = The circuit or contacts are Open (not touching), and no current can flow.
    The description above is opposite and wrong.

  10. I have one on coach and toad. I do not recommend the ones on the battery due to risk of gas explosion. Don’t ask why I know..

  11. The basic concept of a battery disconnect switch is good. However, you need to be aware of some of the pitfalls. For example, in a tow behind or 5th wheel, the brakes are connected to the battery and need to remain connected for safety. If your trailer comes loose while towing, you won’t have any trailer brakes if the battery switch is off. The same applies to propane sensors, carbon monoxide sensors and fire alarms. The brakes and sensors should never be disconnected from the battery.

    We usually treat the brakes and sensors as a separate circuit from the rest of the coach. This requires that the installation of a battery switch only disconnects the fuse panel, not the brakes and sensors.

  12. Your picture shows you wearing surgical gloves during the product installation. I would advise against that. They are extremely flammable and will cling to a surface like napalm. I use to use them to start campfires as opposed to lighter fluid. They smell terrible burning but man do they burn!

  13. I see a lot of comments about depending on the factory disconnect switch. That’s purposely wired so that it doesn’t turn off the propane/CO detector (code, I believe), the tongue jack, and the emergency brakes. The jack and brakes won’t draw power in storage (unless you screw up and pull the pin, then your battery will be dead within 12 hours) but the detector alone will eventually kill your battery. The battery-mounted shutoff will solve this problem, but will also cut off the brakes so by law should never be disconnected while towing.

    To the guy who asked if he can disconnect the battery when on shore power, yes… but the battery will not charge, and if you try to use high-amp systems like a slide or leveling jack that needs the battery as a “storage tank” for drawing high current, you can damage those systems.

    The only time I can envision using the battery-mounted cutoff is when I’m going to leave my rig at the dealer for more than a week or so, or when I’m working on 12V systems where the instructions begin with “disconnect the battery.”

  14. You don’t hook the positive and the negative to the switch, that’s a short circuit when letting current flow through. You splice the switch in the negative side of the DC system.

  15. While I personally don’t see the need for an additional battery disconnect in an RV that already has one by the diesel engine and the usual 12V accessory switch by the entrance door, I have often used on one our tow car. We tow a 2020 Chevy Bolt EV on a dolly. But towing it does not require disconnecting its 12V battery. The Bolt’s software is buggy and has been since the 2017. Briefly disconnecting its battery “reboots” its 12V system, required when Android Auto fails to see anything plugged into its USB ports or when the audio input jack doesn’t work for playing your MP3 device. Unfortunately, doing that also resets your charging preferences and other settings.

  16. RV Disconnect Switch! Or just a battery disconnect switch. I bought one at an auto supply store. I installed it on 2014 Kia, Sportage. The Kia comes along for the ride on the Kar Kaddy SS Tow Dolly behind our Bounder. I know. Why not a towable 4 on the floor, right? It was paid for, no need to spend any more money.
    Ok, to the point, the dealer where we bought our Fleetwood, Bounder; & the Kaddy manufacturer stated that the Kia, Sportage is towable on the Kaddy. Therefore, we towed it around for two years. While in Western N.Y. we couldn’t turn the steering wheel to get the car off the Kaddy.
    We finally got it of by getting the shifter into neutral. Long story longer! The Sportage ended up at the Kia dealership.
    $1200 later, the technician stated that yes! the 2014 Sportage is towable on the tow dolly. However, you MUST leave the key in the ignition SET to accessories and the shifter in park; to not DAMAGE the gear connections on the steering column!!!
    In order to NOT DRAIN the battery while towing, THIS IS THE WAY!
    Therefore, the need to have a quick Battery Disconnect Switch. One drawback is losing the radio settings and any other electrical settings. No big deal to us!

  17. There is lots of information here for rv battery disconnect switch.
    Why you need one
    How to install
    How to use it
    There is No information
    On how to pick the right disconnect switch.
    There are many disconnect switches to pick from with different
    Amperage limits.
    No where on the web can you fine out what amperage disconnect switch is the correct one for your coach.
    275 amp
    600 amp ect.
    Just my two cents

  18. I added a knife blade type of disconnect on the negative side of my house batteries. Yet, some things still worked. I assume the power was going through the battery isolator.

  19. I always used the factory disconnect and still had dead batteries after sitting in storage for a short time. Got two new batteries and had the same issue. Added disconnects to both batteries and mounted a 50w solar panel outside to charge them when in storage. Consistently have 13v-14v when I connect them. I don’t even bother with the factory disconnect anymore.

  20. very good info I raced sport cars and we had a battery switch on all the cars it saved your battery but in a wreck it could save your life.

  21. My Jeep suddenly developed an electrical issue. It would run, start, etc., all day. Park it overnight, and next day battery was dead. Jumped it to start it for a few days, then put a knife blade disconnect on it. At night would disconnect the blade. In the morning would reconnect it. Never had any problems with it dying over night again. And no one, mechanics included, was ever able to figure out what was causing the battery to die over night. Before the knifee blade disconnect used one where you unscrewed the connection – that was a real PITA so switched to the knife blade. Cost around $17, and was more than worth it.

  22. One caution when removing battery leads. Check first with your manufacturer’s instructions, then check with your inverter/charger manufacturer. Some I have found that they require removing the Positive (red) cable first, and install last. Removing the negative(black) first can cause costly damage to the power control system. Removing black first on chassis battery is what is recommended, but not on house batteries.
    So research and check before you do disconnect.

  23. I installed knife style disconnects on both the toad (Honda Fit) and the RV. Without the disconnect, the batteries would discharge. Simple solution to irritations. I also have one of the small battery packages that will restart either vehicle easily.

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