**It is not safe to run your inverter at its full capacity,** which as a result may cause damage to your inverter or appliances connected with the inverter

that is because of the inverter efficiency rate and the type of inverter you have.

Like, the difference between a pure sine wave inverter and a modified sine wave inverter, and what can you run with both of these?

Also choosing the right size battery and wire cable is also very important, Which I’m gonna share with you guys in this short guide.

**What will a 1500-watt inverter run?**

in short, **You can run up to 1300 watts of output load with a 1500 watt inverter e.g fridge, TV, mini microwave, Laptop, Space heater, etc... This can be a single appliance or a combination of appliances but the total watt consumption should not exceed 1300 watts **

You must be thinking that if you have a 1500W inverter you can run up to 1500 watts of load with it. well, it’s not that simple

**Why 1300 watts of load when it says it can support 1500 watts of power?** well, the answer is because of its efficiency rate, Which I’m gonna cover in a moment.

There are a lot of things to keep in mind before running the load on your inverter like what size battery should you use and what size cable will be suitable to pass this amount of load.

first of all, let’s discuss the job of an inverter, its efficiency rate and how it will affect the load capacity, and also what is the maximum surge rating in the inverter.

**Introduction to an inverter, Efficiency rate, & Surge power**

As we know that the job of the inverter is to convert Direct current (DC) coming from the battery into Alternating current (AC) so we can run our household appliances that require AC current.

**While converting DC into AC there will be a power loss due to the inverter’s efficiency rate**. Inverters are not 100% efficient but the standard inverter efficiency rate is 85%.

This means if you have a 1500W inverter so to run 1500 watts of load it will have to pull 1725 DC watts from the battery (1500+15% = 1725).

So your inverter will have to handle more power than its capacity. This as result will increase the internal temperature of your inverter and if you’re running it continuously beyond its full capacity this can cause internal damage

**A rule of thumb is to minimize 15% of your inverter’s full capacity to get the value of the total load you can run on your inverter**.

Minus 15% for 80% efficient inverter, 10% for 90% efficient inverter, and so on…

**For example:** if you have a 1500W inverter with 85% efficiency rate (1500-15% = 1275)

That is why I have mentioned 1300 watts of load in the above answer session.

**Maximum Surge Rating**

in simple words, A surge of power is a burst of power to run the appliance which will last for a few seconds.

**When an inverter is rated at a certain number of Watts, that number usually refers to its continuous rating. But the maximum surge rating in an inverter is the amount of maximum power it can provide for a small duration of period to start the appliance which requires a surge power**

Some appliances, especially the ones with electric motors need surge power in order to get started. **e.g** fridge or refreeze, microwave, dishwasher, clothes washer, vacuum cleaner, etc needs a surge power in order to get started

So the good news is that most of the inverters do support the surge power. The surge power limit will be between 2x-3x of its full capacity

Like this Renogy 2000W inverter has a surge maximum surge rating of 4000 watts

So your 1500-watt inverter will be able to provide 3000 watts of maximum power which will last for a few seconds. (Make sure to check if your inverter has surge ratings)

If it doesn’t so you won’t be able to run large appliances which required surge power to get started.

**Must Watch** – Pure sine wave Vs modified inverter & what they can run?

**will a 1500-watt inverter run a refrigerator?**

The power consumption of the fridge is usually between 100-250 watts. So **Yes**, a 1500-watt inverter will easily run a fridge/refrigerator.

If you’re thinking about running a fridge then you should have a **pure sine wave inverter** type

Also, the fridge requires a sudden burst of power at the initial to get started which will be between 400-600 watts which a 1500-watt inverter can handle.

**Will a 1500W inverter run a microwave?**

The power consumption of a microwave is usually between 800-2000 watts (depending on the size of the microwave)

**if you have a small microwave that has a power input of less than 1300 watts then you can run it with a 1500-watt pure sine wave inverter**.

**What size battery & cable for 1500 watt inverter**

What size and battery for your inverter will highly depend on the total output load. if you’ll use it at its full capacity then I would suggest you go with a 24V inverter and battery system.

Becuase if you’ll have a 12V system you’ll require a very thick wire which will cost you a lot of money. **Why?** (Amps = Watts/Voltage)

if you’re running a 1300 watts of load on your inverter with a 12v battery

`1300/12 = 108 amps`

To pass is the amount of huge current you’ll very thick wiring system like 2 AWG cable size

**Here’s a chart with the inverter voltage, its capacity, and what cable/fuse size you should use.**

Forget about the inverter capacity size, just keep in mind how many watts of load You will run on your inverter then calculate the number of currents (amps) with the help of this you’ll be able to see what size of cable will be suitable.

Also, the number of input amps in the chart is high because of surge ratings.

So if you’re running any appliances like fridges, microwave keeps in mind that you’ll have to calculate the current by putting the surge wattage of your appliance.

**The size of the battery for 1500 watts inverter** will depend on the c-ratings of the battery.

In short, **you’ll need two 12V 100Ah lead-acid or AGM batteries connected in series or a single 100Ah lithium battery**.

There are many things to look for before sizing the battery capacity for your 1500 Watt inverter. like battery type, C-rating, how many hours you would like to run the load, etc…

I have discussed all this in another blog which you can read to get in-depth knowledge about it.

**Must Read:** How many batteries for a 15000W inverter?

**How long will a 1500-watt inverter run?** will depend on the output load and battery size. e.g 24v 100Ah lithium battery will last 1 hour and 30 minutes with a 1500W inverter running at its full capacity

**Final Words**

You can run up to 1500 watts of output AC load with 1500 watt inverter but, running your inverter at its full capacity can be dangerous for the inverter and the connected load.

So you can safely run up to 1300 watts of AC output load with 1500 watt inverter.

**Related Posts**

- 1500 Watt Inverter: Battery Sizing Guide
- What Will An Inverter Run & For How Long? (With Calculator)
- Charging Battery While Connected To Inverter
- Can I Use Solar Panel And Inverter Without Battery?

I hope this guide was helpful to you. if you still have any queries don’t hesitate to Contact Us. Thank You!