What is an RV Battery Disconnect Switch and Why and When You Need This

Today’s modern RVs are equipped with all sorts of new bells and whistles that constantly drain power from your RV’s battery when it’s plugged in but not in use. Especially when the vehicle is parked for extended periods of time or electrical repairs are being made. Constant power consumption can affect the longevity of the battery.

And this is where a battery disconnect switch for RVs comes into play.

An RV battery disconnect switch is the most cost-effective and easy-to-integrate solution for temporarily cutting power to a circuit without manually disconnecting the RV battery bank.

It not only extends the life of your battery, but also protects your RV from electrical fires and theft when the equipment is not in use.

In this article we will discuss what an RV battery disconnect switch does, how and when to use it, and the importance of having a battery disconnect switch on your RV.

What is an RV battery disconnect switch and what does it do?

An RV battery disconnect switch is a device that cuts off the flow of electricity from the coach batteries to the RV cabin.

Depending on the model, you may find this battery disconnect switch in various locations on the motorhome. In most cases, the switch is located on a control panel inside the motorhome.

For example, on my old Fleetwood Bounder, it was located above and to the left of the entrance on a control panel that also contained the gauges for my motorhome’s holding tanks.

In other cases, however, you will find the disconnect switch for your RV battery in the battery compartment itself.

Knowing where the switch is located on your RV is important for certain storage and maintenance operations.

Why is a battery disconnect switch important for RVs?

The main reason for equipping RVs with battery disconnect switches is to protect RV owners and mechanics when performing maintenance and repair work.

However, the battery disconnect switch also helps to maintain the health of the batteries and prolong their life.

In addition, your battery disconnect switch is extremely important in an emergency.

If an electrical fire breaks out unexpectedly in your RV, you may only have a few minutes to find and flip your battery disconnect switch to prevent permanent and catastrophic damage.

How does the battery disconnect switch work in the RV?

All RV batteries can be disconnected manually. To do this, you must open the hood or engine cover and remove the cable (or cables) connected to the negative terminal (or terminals) in the battery compartment.

This procedure can be cumbersome and downright inefficient for certain operations.

It can also be dangerous if done improperly, causing unnecessary wear to the battery cable and the clamp itself.

When the switch is activated, these two cables are disconnected so that no current can flow between them.

When the switch is deactivated, the two wires come back into contact and allow power to flow to the lights and appliances in your RV’s cabin and the compartments below.

When should you use the battery disconnect switch in the motorhome?

There are two main times when you will use your RV’s battery disconnect switch: when you are preparing your RV for seasonal storage and when you (or someone else) wants to perform maintenance.

Let’s go into a little more detail about each of these reasons for turning on your disconnect switch.

Preparing your motorhome for storage

If you are storing your RV without connecting it to a shore power source, it is advisable to activate the battery disconnect switch.

This will prevent devices from discharging your battery while you are not actively monitoring the state of charge.

Even if you unplug all devices in your RV during storage, they can draw a small charge that will discharge your battery.

This is especially annoying when you return to your RV to prepare for your next trip and find that the batteries are dead.

Even RV batteries lose a small amount of their charge over time when disconnected.

For this reason, many RV owners manually disconnect their batteries and move them to a garage or more climate-controlled area while their vehicle is in storage.

Storing your batteries in a place where they won’t be exposed to extreme temperatures will reduce charge loss and make it easier to connect the batteries to a trickle charger so they’re fully charged and ready to go when you prepare your vehicle for the next trip.

Perform routine or emergency maintenance

Before performing routine or emergency maintenance on the RV, it is also important to turn on the circuit breaker.

For example, if you need to disconnect power to your RV freezer to defrost it and remove excessive ice buildup, it’s much easier to flip a switch than to disconnect the refrigerator and freezer from power altogether.

This is also an important step if you ever need to perform emergency maintenance on your RV’s electrical system, service the air conditioner, or replace certain mechanical components such as the air compressor or drive belt.

To put it as simply as possible, you need to make sure that there is absolutely no risk of electric shock before performing any routine or emergency maintenance on the RV. Turning on the battery disconnect switch is the best way to do this.

How to install an RV battery disconnect switch?

Like everything else on your RV or camper, your RV battery disconnect switch has a limited life.

When it wears out and no longer does its job effectively, replacing it should be a top priority, and you need to know how to find and install a new model.

If you have concluded that your disconnect switch is defective, here is a brief overview of the steps you need to take to install a new one:

Find a compatible replacement breaker

The first (and sometimes most difficult) step in this process is to find a replacement switch that is compatible with your RV model.

Fortunately, you can find detailed information about the original manufacturer of the switch in your RV’s owner’s manual.

If you have trouble finding this information in your owner’s manual, you can also call the manufacturer directly or ask an RV electrical technician for a professional opinion.

Manual disconnection of the motorhome batteries

If your old switch was installed on the negative cable of your batteries, you only need to disconnect the negative cable to stop the flow of current through the cable.

However, if your old switch was installed on the positive cable, we recommend disconnecting the cables from both battery terminals before proceeding.

Remove the old switch

Next, you will need to remove the old switch by disconnecting the wire ends that go from the battery to the switch or camper cab.

This will leave two copper wire ends that you can connect to the new switch.

This assumes, of course, that your motorhome was already equipped with a disconnect switch and that you are not installing it for the first time.

If this is the case, you will need to cut the battery cable at a convenient location and then peel off some of the outer protective layer to expose enough cable to allow you to install the switch.

Installation of the new switch

We recommend installing the disconnect switch on the negative cable to your batteries.

Some manufacturers have the switch installed on the positive lead, but the negative side is the safest solution.

If you disconnect the positive lead and leave the negative lead connected, a short circuit may occur if the positive lead accidentally comes into contact with the frame of the RV.

This is unlikely if the end of the positive cable is still connected to the terminal, but you can never be sure if anything has moved in the motorhome engine compartment while you were driving.

That being said, you will most likely need to replace the existing switch to match the current configuration of your RV.

If your old switch was installed on the positive terminal, you will need to work with it and should make sure both wires are disconnected before installing the old and new switch.

Most new switches come with mounting holes so they can be permanently installed in your battery well or compartment.

You don’t want your switch dangling loosely under your RV, as this puts unnecessary stress on the connection points and makes a loose or faulty connection more likely.

Reconnecting the batteries

Once you have mounted your new switch and made and insulated the cable connections, it is time to reconnect the battery cables and test your work.

Pay attention to what position your switch is in before you connect the battery cables.

If you do not operate the switch (i.e., turn it off), your RV appliances should be supplied with DC power as soon as you reconnect the positive and negative cables to your batteries.

If the switch is on when you connect the cables, you will have no power in your RV until the switch is turned off again.

Many owners recommend reconnecting the cables when the switch is on. This prevents a power surge from damaging your appliances.

You can then use a multimeter to check for power to the breaker before closing the circuit, and perform a final test by checking your RV appliances.

Best RV Battery Disconnect Switch

For those of you who have found that your breaker is defective and needs to be replaced, we have compiled some of the best replacement models to choose from.

1: Nilight – 90015A Waterproof Battery Disconnect Switch.

The Nilight battery disconnect switch has a life expectancy of two years and operates at a maximum operating voltage of 48 volts.

It features a rugged construction with an ABS plastic housing and a rear cover for better insulation against short circuits.

This switch comes with four screws and has pre-drilled mounting holes for quick and easy installation.

It can also be used as a stand-alone switch or connected together with a second switch.

2: GAMA Electronics BS200 battery main disconnect switch.

Manufactured by GAMA Electronics, this disconnect switch is designed to mount directly to the top terminal of your RV battery.

It is made of brass and is rated for a maximum current of 200 amps.

This switch is designed to be easily installed as a replacement for the existing terminal at the end of the negative battery cable.

It provides a secure connection, and to disconnect the battery, only one knob needs to be turned instead of manually removing the entire clamp.

3: Blue Sea Systems B01E53G7QI m-Series Battery Switch.

Blue Sea Systems’ Battery Disconnect Switch is designed to universally fit all motorhomes, campers, fifth-wheelers and other types of recreational vehicles that require a disconnect switch.

It is rated for a maximum current of 300 amps in continuous operation and up to 450 amps in intermittent operation.

This is a dual circuit disconnect switch that allows you to connect two isolated battery banks.

It then features a “make-before-break” design that allows you to seamlessly switch between battery banks without interrupting power, or completely disconnect both banks if needed.

Conclusion

There are many mechanical maintenance tasks that require disconnecting power to the equipment in your RV.

The procedures for servicing your refrigerator, air conditioner, RV furnace and other appliances all begin with the important step of disconnecting the appliances from the power source.

Your RV’s battery disconnect switch makes servicing these appliances (and even your RV’s engine) much more efficient.

You no longer have to manually disconnect your RV battery to ensure your safety.

However, it’s a safe bet to test your RV’s battery disconnect switch periodically.

It’s better to make sure it’s working properly than to suffer the consequences of trying to service a device that still has power flowing into it.

We hope this article has taught you a little about RV battery disconnects, why they are important, and how to use them properly.

As always, we wish you the safest and most adventurous RV travels!