Should Inverter Be On When Plugged Into Shore Power? Ultimate Answer

Your RV inverter provides AC power when not plugged into shore power. So what should you do when plugged into shore power? Should you keep your inverter plugged in? Does it do any harm to you or your RV?

There are some advantages and disadvantages when leaving your inverter on all the time when plugged into shore power. For starters, having your inverter on when plugged into shore power has your ac current ready should shore power suddenly cut out. On the other hand, keeping your inverter on when not needed will consume power and create some wear and tear to the life of your inverter. This post will review all the advantages and disadvantages, including:

  • Power
  • Battery
  • Charger
  • Solar Power

Knowing the pros and cons of leaving on your power inverter will help you decide what is best for you.

Table of Contents

Advantages

Let’s first review the advantages of leaving your inverter on when plugged in.

Power

When you always leave your RV inverter on, the main advantage is that you are ready for ac current should you have an interruption with shore power. Many things can happen to shore power, which can go off at the most inopportune times, especially if the power goes off at night. If your inverter is on, it will take over your ac system, and you won’t need to get out of bed to turn anything on.

Depending on the type and size of your RV inverter, it can automatically take that dc power and give you that 120V ac instantly. For instance, if you have anything plugged into your outlet, like a fan, that will continue to run automatically with the inverter power. Also, small ac appliances, such as microwaves and electric refrigerators, will continue should the shore power get disturbed.

Depending on the size of the inverter, you will likely not be able to run your air conditioner. A small RV air conditioner will need at least 3,000 watts of power. And to run that amount of watts through a DC battery will require a large battery bank to power for any length of time.

Disadvantages

Where there are advantages, there are also disadvantages.

Power

There is a disadvantage to having your inverter on all the time, and that is power consumption. Even when there is no ac load that the RV inverter provides, it still consumes power on standby. Even a smaller 1,000-watt inverter will consume 0.9 Amps. That may not seem like much, but consider that this will run 24 hours daily when plugged in. That is over 21 amps of power wasted in one day!

An inverter consumes power just by being turned on

If you a looking to conserve energy, it may be in your interest then to not keep the inverter plugged in if not necessary.

Battery

With that power consumption comes the talk about battery life and battery capacity. Your house battery is the main source of power for your RV. Even when plugged into shore power, your house battery is the power source for most of your motors and life safety features. Visit this post to see everything that your battery powers in a travel trailer.

Most batteries used for inverters are a lead acid battery. There are updated choices, such as AGM and a Lithium battery that provide additional capacity and longer battery life. As you use any electrical appliance, battery voltage reduces your battery capacity. 

As you keep your inverter turned on, it demands power from your RV battery. Although it doesn’t sound much at just under an amp an hour, the battery capacity is reduced, and it will need to be charged more often.

Sometimes, people use a battery disconnect switch to reduce battery consumption when not plugged into shore power.  This battery disconnect will help if you leave on the inverter when not plugged into shore power. 

Charger

As your RV inverter is left on, it drains your battery like any other household appliance. This may not be a concern as your converter is working on charging the battery and providing that needed dc power. As your battery drains, the RV converter works as a battery charger.  And since the inverter is on and consuming battery power, you are also working your converter more to keep the battery fully charged.

Solar Power

We just reviewed battery capacity and how the inverter uses power for just being turned on. If you are connected to solar power or a generator as your shore power, using unnecessary ac power may be more of your concern.

An additional 20 amps per day of lost power will reduce your solar panel’s capacity and limit your reserve capacity.

Wear and Tear

One last thing to consider is the wear and tear of leaving on an electrical appliance that is not needed.  As the power inverter stands idle, there is lost power, and some heat will be generated. The inverter fan will occasionally run to keep the fan from running continuously. Having this run unneeded does reduce the life of the inverter. 

Final Thoughts

Should the inverter be on when plugged into shore power? The answer is yes, and doing so has some advantages and disadvantages. Your main advantage is that you have backup power ready on demand should there be an issue with shore or generator power. This allows you to keep an ac appliance going without disruption. However, there are a few disadvantages, including wasted power consumption, added work for your converter, and more strain on your solar panels to keep up.