ZKETech EBC-A20 Capacity Tester 30v 5a Charge 20a Discharge
These testers are awesome and a great tool to have for battery testing. They are brand new and we use this brand here to test all of our 12v batteries. We have a large testing cabinet with dozens of these. They all have been working flawlessly for years.
You can program this and connect it to your computer for full control and create charts. You can set this to charge, discharge, and recharge to properly test batteries. It will show you the capacity as well.
For example to test a 4s lifepo4 12.8v battery you can program it to charge up to 14.6v at 5a until the amps reach a 0.2a cutoff, then have it automatically discharge at 8 amps down to 10v cutoff, then recharge up to 12.8v nominal voltage.
Note: you can charge from 0-19 volts and 0-5 amps. You can discharge from 30-0 volts and 0-20 amps. If you need to test 24v batteries you can use a separate charger then use this to discharge.
To connect to your computer you need to download the driver (click here) then download the EB Tester software (click here). Note: if you have a windows computer in S-Mode you can disable that first. Go to microsoft store then search "switch out of s mode" then click "Get". S-mode is usually enabled for laptops with little memory so it doesn't allow you to download anything outside of the Microsoft store to save storage memory.
Next you can power on the tester and connect the USB adapter (included) from the tester to your computer.
Open the software then you will see Comm Setting. Select the Com Port of your USB and click connect. Com Ports will be a number between 3-9. If this is the only USB you have connected it will likely show up as Com3.
Now you are connected to the tester and Cycle test tab will appear on the top right. Click on Cycle Test. Then Setting on the bottom right of the screen (not the top setting tab). Now you can program the steps and parameters of your test. Keep in mind you can charge 0-19v and 0-5a. For discharge the range is 0-30v and 0-20a.
For this example we are testing a 12.8v 22ah lifepo4 battery.
Step 1 you will select Mode as C-CV (Constant Voltage). Current (amps) 4. Volt 14.6. Cutoff 0.2. This means the battery will fully charge at 4 amps until it reaches 14.6v then it will continue to charge until the amps drop to 0.2. This means a full charge. Then we selected Add.
Step 2 we have chosen Mode as D-CC (Discharge constant current). We selected current to be 4a and voltage cutoff to be 10v. Then we selected Add.
Step 3 we want to recharge but only to nominal voltage. Mode is C-CV again. Cutoff 0.2a. Current 4a. Volt 12.8v. Then we selected Add.
Now that we are set up to the correct parameters select OK.
Now you will notice the parameter settings are loaded on the next screen. Connect your battery to the alligator clips. Click on Start.
The tester will fully charge to 14.6v at 4a until the amps drop to 0.2a. Then it will discharge at 4a until the voltage reaches 10v. Then it will recharge at 4a until the voltage reaches 12.8v and the amps drop to 0.2a for an exact full charge.
Below is the finished result of that battery we tested.
Notice the red and blue lines in the chart. The red line represents the amps and the blue line represents the voltage. This battery started at 12.3 volts. When we hit start the amps increased to 4 and the voltage went up to 14.6, then you'll see the amps dropped slowly until it reached 0.2 amps for a full top charge. Then it switched to discharge. You'll see in the middle of the chart the amps went back up to 4 as the voltage dropped until it reached 10 volts. Then it recharged back to nominal voltage and reached 12.8v at 4a until the amps dropped to 0.2. The D-CC shows the 22ah battery tested at 23.91ah. Total watt hours 307.85. The test took 12 hours 40 minutes. If you are testing a lithium ion battery you will notice the discharge curve is more angled compared to lifepo4 which tends to hold a steady curve near nominal voltage.
You can save test parameters as well then reopen it easily on that screen. Also if you want to change the title just click on Setting at the top tab and then Curve Title.
You can also use this unit for single cell testing too. This is perfect for all batteries up to 4s configuration to use as a charge and discharge tester. For 24v batteries use a different charger then you can just program this unit to do a discharge. You should always test your batteries with a BMS connected and in a safe area. This will display the capacity after the test is complete and also show you the charge and discharge curve in the chart.
For the English manual click here.