Should I Disconnect My RV Battery When Plugged In To Shore Power?

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Do I need to unplug my battery before plugging into shore power when I pull into the RV park? you may be asking yourself.

Considering that your RV already has a battery bank, is having two sources of power available simultaneously dangerous?

When hooked into shore power, your battery often doesn’t need to be removed.

But in a few exceptional circumstances, you may choose to cut the connection.

Let’s first take a closer look at your RV’s electrical systems.

The appropriate time to unplug your RV batteries will next be discussed.

AC And DC Electrical Systems In Your RV

There are two distinct electrical systems in your RV, one for AC power and the other for DC power.

But how do they differ?

AC Power

The term “alternating current” refers to the fast, back-and-forth direction shifts that occur 50 to 60 times per second while using AC electricity.

The voltage of AC electricity is around 120 volts in North America (and most of South America).

In a normal house, AC electricity is what exits the wall outlets.

To function effectively, the majority of consumer devices need AC power.

Most often, a shore power connection is used to power the AC power system in your RV.

Your consumer gadgets as well as other non-DC equipment in your RV may be powered by this method.

Suggestion reading: PopUp Camper Battery: The Unlimited Guide

DC Power

The term “direct current” (DC) refers to electricity that only travels in one direction.

DC power is used by the majority of batteries, including those in your RV.

Additionally, DC electricity typically has a voltage of 12 volts.

The battery bank in your RV supplies power to the DC electrical system.

The lights, slides, and several appliances in your RV are all powered by this system.

Inverters and Converts

Converters and inverters are two additional crucial parts of your electrical system that we should highlight.

These convert power from DC to AC or the other way around.

Most RVs already have a converter installed, which converts AC power to DC electricity.

Your converter can power your DC equipment and charge your batteries when it is connected to shore power.

DC electricity is converted to AC power via inverters.

They are still widespread and highly helpful even if they are not often included with RVs.

Even without a shore power connection, the inverter enables you to utilize the electricity from your batteries for your AC gadgets.

When should I disconnect RV battery?

So, when you plug in to shore power, should you unplug your RV battery? Most of the time, no.

Although being hooked into shore power isn’t always a good idea, there are specific situations when you should disconnect your RV’s batteries.

Your RV’s converter uses the electricity from the shore outlet to charge your batteries while you are plugged in.

Additionally, it directly powers DC-powered gadgets, keeping your battery from being discharged.

When should I disconnect RV battery?

When using shore power, there are only three legitimate reasons to disconnect your battery:

  • An outdated, ineffective converter without overload protection is in your RV.
  • In this situation, unplugging the battery will stop it from overcharging.
  • You wish to use a different smart charger to charge the battery.

Disconnecting your battery while using shore power after it has been charged will help it last a little longer.

Your batteries should continue to run with a shore power connection in all other circumstances.

However, it doesn’t follow that there are never any valid reasons to unplug your batteries.

In actuality, a lot of RV batteries either ship with a battery disconnect switch or have one added later.

A battery disconnect switch, however, is not necessary.

The primary purpose is to lessen battery depletion while your RV is idle for an extended period of time.

Even when they are turned off, your devices continue to use a tiny amount of power.

This may be avoided by disconnecting the battery, albeit the batteries will still deplete but much more slowly.

Therefore, disconnect your batteries if you anticipate being gone from your RV for a lengthy time, such as when you store it.

RV Battery Disconnect Switch

You may always walk outside and pull the positive and negative load cables to unplug the batteries from your RV.

This method disconnects your camper from the home batteries and works wonderfully.

The main drawback is that replacing the load wires on RV batteries takes a long time, particularly if you have other devices attached or a big battery bank with several batteries and cables strung throughout.

A battery disconnect switch is one addition you may make to greatly simplify the procedure (click to view on Amazon).

How It Works

The action of physically disconnecting the wires from the battery terminals is accomplished by a battery disconnect switch, sometimes referred to as a battery isolator.

By leaving a hole in the circuit on either the positive or negative side, it breaks the link between the batteries and the RV.

Since the general rule is to connect the positive load first, then the negative, it is advised to put an RV battery disconnect switch on the negative side of the battery.

Technically, when you turn the batteries back on, you always connect the positive first, followed by the negative if the switch switches off the negative.

Just so you know, it also prevents the converter from charging the batteries in the RV.

In what location

The location of a battery isolator switch might really vary greatly.

What sort of RV battery disconnect is being utilized actually makes a difference.

If the master switch has both a switch and an isolator built into it, like this one (click to see on Amazon), it will be placed near to the batteries.

However, I’ve also seen travel trailers with a switch like this located inside the front beneath storage.

The majority of folks will install one directly on the battery box.

Typically, a switch like this is just a few feet away from the batteries.

A rocker switch similar to this one (click to view on Amazon) that is linked to a solenoid or relay (click to view on Amazon) that does the actual disconnecting is the second kind of RV battery disconnect switch that is often seen in motorhomes.

It may be difficult to locate the battery disconnect solenoid.

Since you must follow the wires from the rocker switch, which is often found just inside the camper door or close to the “control center” where you can see all of the tank and battery levels, you can truly find it anyplace in a motorhome.

Why Use It?

Even if everything in your camper is off, minor appliances will still draw power from the batteries of your RV.

The carbon monoxide sensors, water heater motherboards, and other devices all need energy, which adds up over time.

It is essential to totally unplug the batteries before storing your RV.

Because you don’t want the fridge to break down and decide to turn on or the carbon monoxide alarm to trip and begin beeping until you return, I advise doing this even if you are going to have a charger attached.

If you want to operate on certain electrical components of your RV, you may quickly turn off the electricity using the battery disconnect.

It serves as a form of safety precaution as well in the event that an RV battery fails or one of the 12 volt appliances begins to malfunction.

Most campers like to have one installed even if they don’t use it all the time, just in case.

Related Also: Does My Travel Trailer Battery Charge When Plugged In?

Effective Factors On RV Battery Life


Your RV batteries might lose electrolyte if you keep it plugged in after it has finished charging.

Unless you have a smart charger, a modern RV converter with a three- or four-stage charging procedure, or if you’ve connected a battery tender, this might result in a reduction in battery life.

You may add distilled water to lead-acid batteries to restore electrolyte levels if they drop due to overcharging, but battery life will still be lost.

Be cautious, particularly while storing RVs over the winter, since overcharging is typical when they are plugged in for months on long without a battery tender.


Sulfation, a chemical reaction that happens when a battery is undercharged, may cause the battery life to be shortened.

Long-term partial charging of batteries results in a buildup of sulfur known as sulfation.

It may stop batteries from converting chemical energy into electrical energy, which would reduce their capacity to store a charge.

Batteries may get undercharged as a result of excessive usage or voltage drop during storage.

The easiest technique to avoid sulfation is to quickly recharge the battery.

The battery should always be between 80% and 100% charged while being stored.

The ideal method to accomplish this is with a battery tender, although a battery tester and regular maintenance are other options.

Biological Loads

When your RV is not in use, parasitic loads like gas detectors, clocks, and other tiny electrical equipment use electricity.

Battery life may suffer if the power drops too low.

Battery disconnect switches on your RV should be activated when the vehicle is turned off or in storage to avoid this.

Temperature Variations

Temperature is another element that has an impact on battery life while being stored.

Batteries will gradually lose their voltage capacity if they are exposed to extreme heat or cold.

So, it could make more sense to remove the batteries and sometimes charge them during the winter if you want to store your RV outdoors while it is plugged in.

Battery life may suffer from freezing.

The Function of an RV Converter

The 12 volt system in a camper may be operated without the need of batteries thanks to the RV converter, which converts 120 volt AC electricity into 12 volt DC power.

Additionally, when you are hooked into electricity, it is what recharges the batteries in your camper.

Your batteries are what power your RV while the converter is off, and they aren’t being charged either.

The breaker box is where you switch on or off the RV converter.

Usually, one of the 15 amp switches is the converter.

How to Recognize a Malfunctioning RV Converter

You may test your RV converter in a variety of ways without any instruments.

First, the lights, fans, and water pump should all operate if you hook into electricity and unplug the house batteries.

If they don’t, your RV converter isn’t converting the AC electricity to DC, which is why.

The RV converter may possibly be failing if the lights start performing strangely and flickering.

If your battery declines even while you are hooked into 120 volt AC power, your RV converter may not be functioning properly.

It indicates that your RV batteries aren’t being charged and that your camper’s 12 volt system is using power from the battery.

The battery indicator on your RV should always show a 100% charge when you are hooked in.

If not, your RV converter may not be functioning if it doesn’t.

There may be a bursting sound coming from the converter or maybe some smoke and an electrical burn smell if it has truly failed.

How To Tell If An RV Converter Is Bad
RV breaker box with the 15 amp breaker for the RV converter turned off.

If it hasn’t already done so on its own, you should in this situation quickly disconnect your RV converter by switching its breaker.

Until the issue has been resolved, you may also wish to unplug your RV’s batteries and disable the electricity.

Recommended reading: Replacing an RV Chassis Battery: Everything You Need to Know

Buzzing Noise from RV Converter

Some RV converters emit a faint buzzing sound when they are connected to electricity.

A little amount of buzzing is typical, and it might also simply be the cooling fan turning on.

Sometimes turning on a light to place a load on the converter will stop the converter from buzzing and alter the frequency.

You may turn the buzzing noise off using the breaker if it bothers you at night, as it sometimes does.

A modern RV converter might be substituted for an older one if yours is creating an obnoxious buzzing noise.

If the noise appears especially loud, there may be a problem with the batteries‘ connection.

Make that the connections at the battery terminals are secure and clean.

Another potential problem is a faulty battery.

There can be a buzzing sound if the converter is having problems charging it.

Only when you are hooked into shore power does the sounds occur.

If your camper has a battery disconnect relay, it may be malfunctioning if the converter is producing sounds while your RV is just powered by your battery.


The electrical system in an RV might be a little daunting, so it never hurts to be extra cautious.

However, there’s no reason to fear in this instance.

Keeping your batteries linked when you are hooked into shore power poses neither a risk nor a problem.

It’s really quite typical, and your RV probably has everything it needs to deal with it.

In order to charge your batteries and operate your DC equipment, your RV’s converter will use the AC electricity from your shore connection.

Related Videos from Youtube

RV Battery Disconnect Switch – What it Does and When to Use it – Colton RV
Why I Removed The RV Battery Disconnect. – All About RV’s
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Ryan is a RV product expert with nearly a decade of experience researching, developing, and testing RV products.

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