Minimum Recommended Battery Options for Inverters:

This is a selection guide to help you choose the right battery to power your 240V inverter. 

12V to 240V Inverter Size

1000W

2000W

3000W

Good

Renogy Core 100Ah

Renogy Core 200Ah

Renogy Core 300Ah

Zeal 100Ah

 Zeal 200Ah  

Better

Renogy Pro 100Ah

Renogy Pro 200Ah

Renogy Pro 300Ah

Projecta 100Ah

Projecta 200Ah

Projecta 400Ah

Best

 

Enerdrive 100Ah B-TEC

Enerdrive 200Ah B-TEC

Enerdrive 300Ah B-TEC

Invicta 100Ah

Invicta 200Ah

 

Victron 100Ah (High Current)

Victron 200Ah

Victron 200Ah

 

*Use the corresponding size battery to calculate how long your appliances can run in the table below.

 

Calculate how long your 240V appliance will run via inverter:

 

Appliance

Power Draw (Watts)

Battery Size Ah

Run Time Hrs (at full load)
x
x
x

 

*Assumes appliance is running at full load

*Assumes inverter has 90% efficiency

*Assumes battery voltage is 12.8

 

Hot Tip: Thinking of running a domestic refrigerator in your caravan?

Although it might sound appealing to pickup a cheap domestic 240V fridge/freezer with a highly efficient energy star rating it is important to understand the whole picture.

To run a 240V fridge your inverter needs to be powered up 24 hours a day. All 240V inverters consume power even when no load is applied. So this is another device depleting your battery storage. Secondly the inverter consumes extra power to convert 12V DC power into 240V power. These losses are considered in the table above. A reputable 12V DC caravan fridge will be more efficient than a domestic 240V fridge. Caravan fridges are designed with greater insulation and can withstand the rigours of mobile applications.

 

Example: Westinghouse 225L Refrigerator

Domestic fridges will provide a kWh/year in this case it is 282 kWh/year. Therefore 773Wh per day.

So 32Wh is the average power draw at 240V. We then add an average of 15Wh for the inverters constant no load power draw, thus the total average is now 47Wh . 

Using the table above this model would run for 39.2 hours from a 200Ah battery.

Comparing with a Dometic RUC 8408 12V 224L Fridge the average power consumption is 3Ah. If you were to run it with the same 200Ah battery as the example above it would run for 53 hours.

This is a huge difference when travelling out on the road and should be considered. 

Starlink dishes operate between 48 and 56 volts (V). The standard Starlink setup includes a 240V plug, which users must connect to an inverter when using off-grid power sources. This setup involves two voltage conversions:

  1. From a 12V battery to 240V using an inverter.
  2. From 240V down to 48-56V using Starlink's equipment.

A more efficient way to power the Starlink Dishy is through a direct conversion from a 12V battery system to 48-56V using the RV WIFI DishyDock for Starlink System. This product can be found here: RV WIFI DishyDock.

This method conserves battery power by eliminating the need to run a 240V inverter, which typically has a no-load power draw even when not in active use.

To power a Dometic 2 Zone Induction Cooktop off-grid you could use an Enerdrive 2000W Inverter and an Enerdrive 200Ah Lithitum Battery. 

This induction cooktop has the following power requirements: Induction zones 1000W (Left), 1300W with Boost Function 1700W (Right)

If you were to run the left zone at 1000W the table above shows a run time of 1.8 hours from Enerdrive 200Ah Battery. 

Another way to look at this is 30 minutes of cooking time would use approximately 22% of the Battery. 

Pro tip: The Enerdrive 2000W Inverter with RCD & AC Transfer Switch and the Enerdrive 2600W Inverter with RCD & AC Transfer Switch are a recommended option for a caravan and RV inverters due to their inbuilt RCD safety feature. 

 

Cable Sizing For Inverters

High powered 240V appliances when connected via an inverter will lead to higher currents (Amps).

Undersized cabling will result in efficiency losses to heat, damage to cabling and appliances and voltage drop. Here is a general guide for cable sizing to connect a battery and inverter:

Inverter Capacity

1000W

2000W

3000W

Recommended Fuse Size

150A

250A

350A

Cable Size 1m

16mm2

50mm2

90mm2

Cable size 1.5m

35mm2

70mm2

120mm2