There are many inverters on the market, how to determine the quality of an inverter, various information on the Internet directly mislead users to make the right choice. We will show you here, what is the standard of a good inverter? We’re going to do some extreme tests to see if the inverter is good or bad; it’s going to be the most brutal inverter test you ever seen.

How do you test a inverter?

The models tested this time are BP series 1000W and 2000W, the main test object is B12P1000-2, DC 12Vdc input, 230Vac/50HZ/1000W output, when we test some actual loads, such as 1.5HP air conditioner, If the controller cannot be started if we use 1000W inverter, we will use 2000W to test whether it can be done.

Test modelB12P1000-2
Input12Vdc
Output230Vac/50HZ/1000W

Main test items:

1. Overload test, 120% load, 150% load, 200% load, 300% load, 500% load, 700% load

2. Short circuit test, 100 times of repeated short circuit, restart after power-on load short-circuit, power on and restart when short circuit occurs.

3. Over temperature test, under the circumstance of ambient temperature of 55 degrees, 100% load running time,

4. Quiescent current, in the absence of any load, the inverter itself loses

5. Conversion efficiency, conversion efficiency at 25% load, 50% load, 75% load, and 100% load respectively

6. Load capacity, mainly use load halogen lamps, air conditioners and water pumps

Combined with the customer’s usage, we use the commonly used load to test the limit of the 1000W inverter, which is not the data of the laboratory, but is closer to the actual situation.

Test itemsContent
Test 1Overload test
Test 2Short circuit test
Test 3Over temperature test
Test 4Quiescent current
Test 5Conversion efficiency
Test 6Load capacity

How do I know if my inverter is faulty?

During the test, we will perform all fault simulations to trigger the protection function of the inverter. Various faults and phenomena will occur during the inverter test, so that users can easily judge the cause of the fault when they encounter the same fault phenomenon in use. There are mainly the following situations.

1. Under-voltage protection, when the battery voltage is lower than the under-voltage protection value, the under-voltage alarm of 12Vdc 1000W is 10.5V, and the under-voltage shutdown is 10V. At this time, the inverter has no AC output.

2. Under-voltage recovery, when the battery voltage recovers to a certain value, the inverter will restart, 12Vdc 1000W is 12.8Vdc, and the inverter has no AC output at this time.

3. Overvoltage protection, when the battery voltage is higher than the overvoltage protection value, the overvoltage shutdown of 12Vdc 1000W is 15.5Vdc, and the recovery is 15.4Vdc

4. Overload protection, when the load is larger than 120%, the inverter will turn off the output after 6 seconds, when the load is 150%, the inverter will turn off the output after 3.5 seconds, when the load is 200%, the inverter will The output will be turned off after 3 seconds, the output will be turned off after 2.7 seconds when the load is 300%, and the output will be turned off after 2 seconds when the load is greater than 300%.

5. Over temperature protection, when the internal temperature of the inverter is higher than 83 degrees, the inverter will turn off the output. When the internal temperature of the inverter is lower than 75 degrees, the output will resume.

6. Short-circuit protection, when the load is in a short-circuit state and the inverter is turned on, the inverter has no output, the inverter is running, and the load is damaged and short-circuited, and the inverter has no output.

 Fault phenomenon simulated
1Under-voltage
2Under-voltage recovery
3Overvoltage
4Overload
5Over temperature
6Short-circuit

Overload Test:

Test objectB12P1000-2, 12Vdc/230Vac/50Hz/1000W
Test equipment0-30V 300A adjustable DC power supply, oscilloscope, power meter, load box
Test conditionsroom temperature 25 degrees, DC input voltage 12Vdc

Overload Test Outcome:

LoadOutput VoltageProtection method
1000W228Vaccontinuous operation
1100W227Vacturn off after 7 seconds
1200W225Vacturn off after 5 seconds
1300W186.5Vacturn off after 4 seconds
1400W182Vacturn off after 3.5 seconds
1500W180Vacturn off after 3.5 seconds
1600W177Vacturn off after 3.5 seconds
1700W172.5Vacturn off after 3.3 seconds
1800W166Vacturn off after 3 seconds
1900W159.5Vacturn off after 3 seconds
2000W154Vacturn off after 3 seconds
2500W132.2Vacturn off after 2.8 seconds
3000W117Vacturn off after 2.7 seconds
3500W106Vacturn off after 2.6 seconds
4000W96.8Vacturn off after 2.5 seconds


Short circuit test:

Test objectB12P1000-2, 12Vdc/230Vac/50Hz/1000W
Test equipment0-30V 300A adjustable DC power supply, oscilloscope, power meter, short circuit device
Test conditionsroom temperature 25 degrees, DC input voltage 12Vdc
SituationProtection
The inverter is turned off, connect to the short-circuit load, turn it on and restartYes
The inverter is in the running state, the short-circuit is suddenly short-circuited, the power is turned on and restartedYes


Undervoltage protection/recovery, Overvoltage protection/recovery Test:

Test objectB12P1000-2, 12Vdc/230Vac/50Hz/1000W
Test equipment0-30V 300A adjustable DC power supply, oscilloscope, power meter, short circuit device
Test conditionsroom temperature 25 degrees, DC input voltage 12Vdc
Input VoltageProtection
10.45VdcLow voltage alarm
9.97VdcLow voltage shutdown
12.8VdcLow voltage recovery
15.6VdcOvervoltage protection
15.5VdcOvervoltage recovery


Over temperature protection test:

Test objectB12P1000-2, 12Vdc/230Vac/50Hz/1000W
Test equipment0-30V 300A adjustable DC power supply, oscilloscope, power meter, short circuit device
Test conditionsroom temperature 25 degrees, DC input voltage 12Vdc, remove the fan

Test outcome:

1. Without fan, 83 degrees, over temperature protection, no output
2. When the temperature returns to 80 degrees, resume the output

Quiescent current test:

Test objectB12P1000-2, 12Vdc/230Vac/50Hz/1000W
Test equipment0-30V 300A adjustable DC power supply, oscilloscope, power meter
Test conditionsroom temperature 25 degrees, DC input voltage 14.66Vdc, no load

Test outcome:

1. No-load current:  14.66Vdc 0.46Amp about 6.75Watt

Conversion Efficiency Test:

Test objectB12P1000-2, 12Vdc/230Vac/50Hz/1000W
Test equipment0-30V 300A adjustable DC power supply, oscilloscope, power meter, multimeter, ammeter, load box
Test conditionsroom temperature 25 degrees, DC input voltage 12Vdc

Test outcome:

LoadEfficiency
30%90%
60%89%
100%88%

Load capacity test:

Test objectB12P1000-2, 12Vdc/230Vac/50Hz/1000W
Test equipment0-30V 300A adjustable DC power supply, oscilloscope, power meter
Test conditionsroom temperature 25 degrees, DC input voltage 12Vdc
Load 1Halogen lamp 500W*2
Load 21.5HP air conditioner
Load 31.1KW water pump

1. Halogen lamp 500W*2

We used an oscilloscope + current probe to check the starting power of the halogen lamp. The 500W halogen lamp has a starting power of 13.3A (230Vac) in cold state, peak power about 3000Watts:

But in the hot state, the 500W halogen lamp start power is only 3.84A (230V), the peak power is 883W. this is completely two states, if your requirements are very strict, you need to use such a test method. But if your inverter does not have enough load carrying capacity and protection, it will be burned out.

And for this test, we used the BP series 12V/1000W inverter to directly drive two 500W halogen lamps and it performed well.

2. 1.5HP air conditioner

Failed when using BP series 1000W inverter for 1.5HP air conditioner. We tried the 2000W inverter and it worked easily and ran in the office for 4 hours with no problems. This time we found that the 1.5HP was running with a current of 100A at the input, which is not possible for the 1000W inverter, and we guessed that it should start at more than 4000W, so the BP 1000W could not run.

3. 1.1KW water pump

We were testing a 1.1KW pump, without any water source, and let it rotate; we found an amazing figure, it ran with a rated power of 2600W as much as possible, which surprised us, if it runs with a load, will it need a higher power?

Of course, we use BP series 1000W to test the 1.1KW water pump, we are not asking to be able to drive this pump, after all, it needs 2600W to run the rated power, if it is the peak function, it may be 10kw, we just want to test in this extreme situation, BP series 1000W inverter, can it protect itself without being damaged. In fact, many inverters would simply burn out in such a test.

Next we will conduct a more brutal test, in a high temperature box, set the temperature to 55 degrees, and then run at full load to see if the BP 1000W can run properly. It is worth noting that we still use 12Vdc 1000W to do the test, because 12Vdc compared to 24Vdc and 48Vdc, the machine itself has a higher temperature rise and generates the most heat. This is equivalent to military grade standards.

BP series 1000W inverter passed the high temperature test, we tested it at 45 minutes, 2 hours, 4 hours and it worked fine, finally we tested it for 10 hours and we think it is one of the best inverters on the market today, it is very stable and fully protected.

We finished the toughest inverter test and the B12P1000-2 performed very well without failure, normally in such extreme tests the inverter would just burn out, but the B12P1000-2 passed the test. The new version of the BP series upgraded in August 2022 once again defines the quality standard of the inverter. We summed up 4 key points that can damage the inverter.

1. The positive and negative poles are reversely connected, which will burn the fuse and may break down the front-rear Mosfet
2. The input voltage is too high, the 12Vdc inverter is connected to 24V, 48V or higher voltage, the Mosfet is damaged, and the capacitor will be burned if it is not removed for a long time
3. The AC output is connected in parallel with the mains. Many users will mistakenly connect the inverter output to the mains when using another battery charger, which will damage the rear Mosfet and the driver board, and will burn the PCB in severe cases.
4. Water leaks in, or long-term use in a very humid environment will cause short-circuiting of components on the PCB. Although we have used conformal paint on the control board, it cannot be completely ruled out that the components on the mainboard will be short-circuited.If the user  can avoid the above four incorrect usage methods when using the inverter, the failure rate of the inverter will be reduced to less than 0.5%.

If you are choosing an inverter, you can refer to our method to test the reliability of the inverter. To be a thoughtful inverter creator will be the constant corporate vision of CNBOU now and in the future.

Last modified: August 29, 2022

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