Inverters are responsible for converting direct current into alternating current for appliances to use. Solar inverters or power inverters both have the same function with one slight difference. Solar inverters take direct current from solar panels and transfer the converted current to solar batteries. Whereas normal inverters take current from batteries and transfer the alternating current to the connected appliances. But do you know inverters consume power even when not in use? How much power does an inverter draw with no load? Do Inverters Use Power When Turned Off? Come find out.
What is No Load Current? Why Does it Matter?
Every inverter is featured with a no-load consumption facility. The amount of electricity consumed by a battery charger (inverter) when it is plugged into the socket is known as idle consumption. During this time, the batteries are not connected to the socket. Another function is standby consumption, which means the inverter absorbs power from the battery even in standby mode.
It is important to understand no-load current because you do not want to waste energy. Here are the two main reasons to do so-
- To get an idea of whether the inverter is consuming more power than the load that is connected to it. For example, sometimes a radio connected to the inverter uses just 5 watts but the inverter itself consumes 10 watts. This is a complete waste of money and energy.
- Secondly, accumulation of no current load like imagine your inverter is left on 24 by 7. Now, with a 10-watt no-power draw rating, it is almost 70 watts per week that will be wasted.
How Much Power Does an Inverter Draw with No Load?
This may sound confusing because at times when the inverter is not connected to any load then also it consumes power. It is because inverters produce waveforms even on standby mode and the larger the inverter is the more power it needs to start.
You can find No Load Current mentioned on the specification sheet as no load current draw (amps) or as no-load power (watts). Now to determine how much power your inverter is drawing without any load, multiply the battery voltage by the inverter no load current draw rating.
Battery voltage = 1000 watts
Inverter = 24V
No load current = 0.4 watts
Power drawn = 24V * 0.4 = 9.6 watts
This formula and calculation are applicable to all inverters irrespective of their size. 12V or 24V is the only thing that will make the difference in the power consumed. Remember, the higher the voltage is the greater the no-load current will be.
In some configurations, a standard inverter may consume between 0.416 amps and 2.83 amps of power in idle mode. But this amount may vary depending on the type of battery bank used and the types of loads connected to the inverter. Typically, in a no-load current, the energy drawn by the inverter is only 2 to 10 watts an hour.
What Amount of Power is Wasted by Inverter?
Do not confuse the inverter’s no-load current with the efficiency rating of the inverter. Efficiency means the amount of power the inverter can convert. The amount of energy preserved during the process is the efficiency rating of the inverter. For example, an inverter with an 85% efficiency rating means that the remaining 15% of energy will not be used and is wasted. However, new inverters have a 90% to 95% efficiency rating that considerably reduces the amount of power wasted, but there are no inverters with a 100% efficiency rating.
In other words, more power is wasted with lower efficiency ratings. And when you sum up this loss with no load current it can be a lot. This is why you should buy an inverter with the highest possible efficiency ratings. This fact is an important consideration in determining how much power does an inverter draw with no load.
So, if the inverter is on the power consumed by it from the no-load current cannot be avoided. However, it can become negligible if connected to a large load. Suppose you are using a 5000 watts inverter and run it at almost full load then 0.4 no-load currents can be ignored. Now, let’s see does an inverter draw power when not in use.
Also See: What is a Central Inverter?
Does an Inverter Draw Power When Not in Use?
Yes, the inverter turned on but not in use will draw power. The amount of power drawn can range between 0.2 amps to 2.0 amps depending on the size of the unit and the standby systems design. So, the answer to does an inverter draw power when not in use is yes it does.
Do Inverters Use Power When Turned Off? Should You Switch Off the Inverter When Not in Use?
Even when the inverter is turned off it is drawing power no matter which brand it is. This is common in most inverters. To calculate the amount of power being drawn by the inverter you should know about its maximum and minimum draw. The former is the highest amount of electricity the inverter uses at a time and the latter is the lowest amount of the same.
Yes, it is a good idea to do so if you are using the inverter for over a long period of time and also if many appliances are connected to it. Once the batteries are fully charged and the inverter is no longer in use, you can turn it off. This will also help to save on your electricity bill.
Do Inverters Consume Power When Fully Charged?
In case the inverters are fully charged they hardly consume less than 0.99% of their capacity. With this, there is little to no impact on the power bills. Also, it would be better if you switched off the inverter when fully charged.
But if using it at full speed while it is plugged in it will consume more power. This sounds tricky, but this activity can be monitored with an energy monitor. Now, you must also be curious to know how much power does an inverter draw from a battery.
How Much Power Does an Inverter Draw from a Battery?
After learning about how much power does an inverter draw with no load, it is time to know about the amount of power drawn from the batteries. Yes, inverters drain batteries if not in use and the amount of power drained depends on the design and size of the inverter. Generally, it is said that modern inverters save more power than traditional ones. And if an inverter is left connected to the batteries without any load, then it will drain the battery completely over time. It will draw from the batteries around 1 amp per hour, 24 amps per day, and around 168 amps per week.
How Many Amps Does a 2000 Watt Inverter Draw with No Load?
Without any load connected to it, a 2000-watt inverter can draw approximately 1.5 amps depending on its efficiency. A 2000-watt 24V inverter can draw approximately 83 amps of continuous current at full load. It is also capable of drawing a surge current of about 186 amps for a fraction of a second, which is typically twice its continuous current. This usually happens when the inverter is connected to large inductive loads like large refrigerators or motors.
|Inverter rating (Watts)
|Battery current (A)
|Output current (A)
|Inverter output (Watts)
|100 – 500
|8.33 – 41.67
|0.33 – 1.67
|80 – 400
|550 – 900
|45.83 – 75
|1.83 – 3
|440 – 720
|950 – 1100
|80 – 91.67
|3.17 – 3.67
|760 – 880
|1200 – 1400
|100 – 116.67
|4 – 4.33
|960 – 1120
|1500 – 1700
|125 – 141.67
|5 – 5.67
|1200 – 1360
|1800 – 1900
|150 – 158.33
|6 – 6.33
|1440 – 1520
|2000 – 3000
|166.67 – 250
|6.67 – 10
|1600 – 2400
Note: Figures mentioned above are subject to change. Check the technical specification section of the inverter model. Here is a table of inverters with different ratings and amounts of power consumed in idle mode.
How to Prevent Inverters from Wasting Power?
Start with looking for an inverter with a very low no-load current and if the system has an on/off switch then it is better. Also, a pure sine inverter is a good choice in this case. And after learning about how much power does an inverter draw with no load, here are a few more things to consider preventing power wastage.
1. Always Check System Efficiency
Here the entire system is considered: solar panels, batteries, charge controller, and other related components. So, for the system to work smoothly with the least possible power wastage, it is necessary for the efficiency rating of all these components to match.
2. Higher Volts Mean Lower Amps
Low voltages will draw more power in comparison to higher volts. Let us take an example here.
Watt load – 230 watts
Inverter – 12V
Here, 230/12 = 19.1
So, the amount of power drawn or wasted is 19.1 watts.
Watt load – 230 watts
Inverter – 24V
Here, 230/24 = 9.5
So, with a 24V inverter, you can see there is a considerable reduction in the amount of power wasted. If you are calculating it for deep cycle batteries, you need to divide the power drawn in half because of their discharge rate.
3. Inverter Watt Rating vs. Power Consumption
How much power an inverter uses is not determined by its watt rating. To know the power consumption, you need to add a percentage to the power used by a load according to the inverter efficiency. For example, an inverter with a watt load of 200 watts and an efficiency rating of 90% will draw 230 watts or 200 watts plus 10% to make up for the inefficiency.
Also Read: Can You Run Inverters in Parallel?
4. Use the Right Inverter System
Different applications require different types of inverters. For an RV a 12V inverter should be enough and for an off-grid cabin or mobile home a 24V inverter is ideal. But for more powered or large applications, a 48V inverter system is preferred.
Well, today you learned how much power does an inverter draw with no load? Depending on the no load current, you can determine the amount of power your inverter is drawing with and without load. To calculate it you should know about battery and inverter voltage, along with no load current rating mentioned on the specification sheet of the inverter. The answer can be calculated by multiplying battery voltage by no load current. How many amps does a 2000 watt inverter draw with no load? The answer to this is 1.5 amps approximately but can differ on the basis of inverter size and efficiency ratings.
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