Inverter Amp Draw Calculator: Let’s Simplify It -
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Inverter Amp Draw Calculator

Short on Time? Here’s The Article Summary

The article discusses the importance of monitoring the amp draw of an inverter in a solar power system to manage battery usage efficiently. It introduces an inverter amp draw calculator to simplify this process. The article explains how to calculate the amp draw based on the size of the inverter and provides a list of estimated values for different inverter sizes.

It also addresses common questions, such as whether inverters draw power when not in use (they do, but it's minimal), and advises on disconnecting the inverter when not in use to prevent battery depletion. The article also highlights the importance of monitoring battery levels to avoid damage and suggests cleaning and maintaining terminals if the inverter is disconnected for an extended period. Finally, it explains how to calculate the amp draw for appliances connected to the inverter based on their wattage, providing a simple formula to determine the amp draw. It offers additional calculators and guides for solar power users to make the process of managing their system easier.


As a solar power user, one of the tools that can help you is an inverter amp draw calculator. 

It can get complicated to monitor usage and battery levels consistently, so we’ve created this guide to make one of those aspects easier.

We’re on a mission to make solar simple, so we’ve also got a range of other handy guides to make this process easy for you. More on that later!

For now, let’s get into how many amps your inverter draws, and why that should be important to you as a solar power user.

How Many Amps Does My Inverter Draw?

The number of amps your inverter draws depends on its size. The larger the inverter, the more amps it uses.

inverter power draw calculator

Here’s a useful list that can help. Your inverter might differ slightly, but the figures will be in this region:

If you have a 1,000W 12V inverter, you can expect it to use between 88 and 105 Amps.

If your inverter is 1,000W but 24V, you can expect it to use between 44 and 52 Amps. 

A 1,000W 48V inverter uses between 22 and 26 Amps.

Once you’ve worked out these values, you can figure out other important things. This is how you convert amps to VA

If you’re using this calculator for your camping trip, check out our RV amp-hour calculator to help you along.

Does My Inverter Draw Power When Not in Use?

Inverters unfortunately draw power from the batteries storing your power harvested from the sun. This is only if it’s switched on, though. If you want your inverter to stop drawing power from the battery completely, it’s best to disconnect it.

This ensures your battery isn’t depleted. We recommend doing this if you’re going to be leaving your house for a while. That way, once you get back, you can be sure that all your equipment is good to go.

inverter load calculator

Yes, the sun’s energy will still be used. It’s important that you’re monitoring your battery levels at all times though. If one of your appliances suddenly starts using more power than it normally would, you run the risk of depleting your battery.

When this happens repeatedly, the battery life is degraded. Eventually, you’ll need to replace it. This can get costly.

Your inverter for solar panels draws current even in standby mode. It’s a lot less current than when your inverter is in active use, but it can add up over time.

An inverter in standby mode can use anything between 0.2A and 2A of current at any moment in time. It all depends on the unit you have, and how it’s designed to operate when it’s not in active use.

If you’re going away and disconnecting your inverter from the battery to avoid depleting it, you should clean the terminals after disconnecting it. It’s also a great idea to apply petroleum jelly to the terminals to keep them clean while you’re away, and avoid the process of erosion.

When the terminals erode, you might not be able to use your inverter when you’re back and reconnect it. The current won’t be able to flow between your battery and inverter.

inverter battery drain calculator

So now that you know how much power your inverter draws when not in use, what about when it is in use?

This differs depending on a few factors, so let’s take you through it.

So, How Many Amps Does My Inverter Draw?

This all depends on how many appliances are plugged into your inverter. When calculating the amps being drawn by your inverter, you need to know the load being drawn. This refers to the load in watts.

So, to put it simply, you divide the load in Watts by 10. For example, if you have an appliance plugged in that has a rating of 300W, you’d divide that by 10 to determine how many amps of current it’s pulling. The answer would be 30A.

If you’ve got a few appliances plugged into your inverter or a circuit run by your inverter, you’d need to repeat this process per appliance in use.

inverter battery load calculator

If you’re not sure where to find the wattage rating on your appliances, don’t worry. There’s usually a sticker somewhere indicating it, or you can find it on the box the appliance came in.

Have a look at our house amp calculator if you want to know the amperage of your entire household.

We can also help you convert volts to amps and convert mAh to Ah.

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Article by

Cody Oehm

Cody is the Head of Marketing at Shop Solar, and joined the company in spring of 2022. 

He has an entrepreneurial background and has been in the ecommerce industry since 2015. With 4 businesses under his belt and a drive to make a bigger impact, he decided to team up with Shop Solar on their mission to make solar simple and affordable. You can browse best seller's here.

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