A **2,000 watt/ 24v** inverter can draw a **continuous current** of approximately **83 amps (2,000W)** at full-load with good ventilation.

It may be able to draw a surge current of about 186 amps (4,000W) for a fraction of a second, typically twice its continuous current.

This can happen when for example it is connected to large inductive loads such as *motors, large fridges*.

It is worth noting that even when no load is connected to the inverter, it can draw approx. 1.5 amps (36 W) depending on its efficiency.

**Note:** For accurate values of the continuous, surge, and no-load current, check the technical specifications section of a particular inverter model.

To calculate an inverter’s approximate amp rating based on its power rating and voltage, use the formula below.

#### Formula for calculating an inverter’s continuous amp rating

To find the inverter’s continuous current at maximum load, use the formula, *I = P÷ V* where:

- I= continuous current (amps)
- P= Inverter power (Watts)
- V= inverter voltage (V).

**Related questions**

#### # 1. Should you get a 12V or 24V rated 2000W inverter?

While you may be able to get a 12V/ 2,000W inverter, in general, Inverters with power ratings up to 750W are usually rated at 12V. Higher power-rated inverters (>750W) will likely be rated at 24V and above. This is done to limit the current levels for improved safety.

#### # 2. Inverter no-load current and why it is important

While an inverter is switched on, it consumes some power and continuously draws a current, the no-load current even when there is no appliance connected to them.

This no-load current level depends on the size and efficiency of the inverter. Higher efficiency models or smaller inverters for example tend to draw smaller amounts of power compared to less efficient or larger inverters.

*This is the reason why an inverter that is switched on even with no appliance connected can completely drain a battery.*

To conserve the battery, therefore, always switch off the inverter if no load is connected or better still use inverters with a power-saving feature which helps the inverter to ‘sleep’ drawing a much smaller current (~4W for some models).

### # 3. What appliances can the 2000W inverter power at a given power rating?

A 2,000W inverter can be used as a backup power solution in the home, camper or RV for appliances such as lights, TV, freezer, light tools, laptops, DVD player, PSP, camera and other electronics provided its power supply capacity is not exceeded.

If connecting several appliances to the inverter, make sure the total appliance load does not exceed both the inverter’s continuous and surge power ratings.

*As a personal rule, I only connect appliances up to 80% of an inverter’s maximum power rating to avoid damage to the inverter.*

*For example, if an inverter is rated 2,000W, I will only load it up to 1,600W to avoid damage. Some inverters can only provide power at their maximum rating for a limited time! *

Below is a handy calculator to help you quickly work out the combined power consumption of several appliances that you plan to connect to the inverter.

Adjust the number of appliances and their corresponding power ratings and check the combined appliance load – this will give you an idea of the appliances that can be connected to an inverter based on its power rating.

*Remember, the combined appliance load (Watts) should be less than the inverter’s power rating!*

**Note:** This is indicative and for guide purposes only. Consult a professional when designing your application.

### # 4. How many batteries for 2000W inverter?

You can use the *inverter battery size calculator* to work out the *battery *size needed to run the inverter at based on its power rating. To use the calculator, you need the following:

- inverter power rating (watts)
- voltage (v)
- expected runtime for appliances (hours)

**Note:** This is indicative and for guide purposes only. Consult a professional when designing your application.

The above calculator is based on the formula described below.

#### Formula for calculating the battery size for an inverter

The calculator above is based on the formula, battery size ((Ah)= P÷V x t)÷ DOD, where:

- P= inverter rating
- V =battery voltage
- t= time that inverter will supply load
- DOD = battery DOD

### # 5. How to calculate the number of batteries in a battery bank

To work out the number of batteries that will make up a battery bank-based, divide the battery size from the calculator by the capacity of the battery you plan to use.

*Example #1.*

To work out how many batteries you need for a battery size of 400 Ah at 24V when using 100Ah, 12 V batteries, first combine 2 x 100Ah 12V batteries in series to get the equivalent of 1 x 100 Ah battery at 24V.

*The number of batteries required for 400 Ah at 24V is 4 x 2 = 8 x 100 Ah.*

Example #2.

To work out how many batteries you need for a battery bank size is 400 Ah at 24V with 200Ah, 12 V batteries, first, combine 2 x 200Ah 12V batteries in series to get the equivalent of 1 x 200 Ah battery at 24V.

*The number of batteries required for 400 Ah at 24V is 2 x 2 = 4 x 200 Ah.*

Sometimes in addition to working out the recommended battery size for an inverter, you may need to know the number of batteries in the battery bank. The batteries in a battery bank calculator below can help you work it out.

The calculator takes into account the inverter voltage, depth of discharge of the battery, and expected run-time of the load. *Battery efficiency is assumed to be 85%, i.e. only 85% of the stored energy is available for use.*

**Note:** This is indicative and for guide purposes only. Consult a professional when designing your application.

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