What is a PV module tester?

Feb 10, 2022 Detection of photovoltaic modules

What is a PV module tester?

Photovoltaic module tester is a device specially used for electrical performance testing of solar monocrystalline silicon, polycrystalline silicon and amorphous silicon photovoltaic modules. Here is an example of a photovoltaic module tester developed and produced by a company.

What is a PV module tester?
PV module testing unit

1. Technical features of PV module tester
A photovoltaic module tester uses imported high-power, long-life pulse lamps as the simulator light source, imported ultra-high-precision four-channel synchronous data acquisition card for test data acquisition, and professional ultra-linear electronic load to ensure accurate test results. Its technical features include the following aspects:

(1) Constant light intensity, to ensure constant light intensity in the test interval, to ensure that the test data is true and reliable. The pulse width of the flashing light is 0~100ms and is continuously adjustable, with a step of 1ms, which can be adapted to the measurement of different battery components.

(2) Digital control ensures test accuracy; programmable control hardware parameters. Equipment commissioning and maintenance are simplified. Using 2M x 4 high-speed synchronous acquisition cards, more details of the test curve are restored, and the actual working conditions of the tested cells are accurately reflected.

(3) Infrared temperature measurement is used to truly reflect the temperature change of the cell and automatically complete the temperature compensation.

(4) Automatic control, real-time detection of the working status of the battery slices and main unit circuits in the entire test range, and software/hardware protection to ensure the reliable operation of the equipment.

Usually photovoltaic module testers are composed of module test box, pulse light source equipment, electronic load equipment, control computer (control and test software), etc. The key technical parameters include the level of the solar simulator, the test area, and the uniformity of the light source. , the repeatability of the test and the test speed.

What is a PV module tester?
PV module testing

2. Operation steps of PV module tester
The operation steps of a photovoltaic module tester are as follows:

(1) Power on.
①Open the air switch inside the device.
②Release the emergency stop switch (see the description of the operation panel).
③ Turn on the key switch and power on the device (see the operation panel description).
④ After the device is powered on normally, start the computer.

(2) Click the “SCT.exe” icon on the desktop to enter the test software (please make sure to insert the dongle).

(3) Click the green “Charge Capacitor” button on the right side of the test software interface. At this time, the “Current Charging Capacitor Status” indicator light will turn from red to green, and the voltage on the “Operation Panel” will rise to the set value.

At this time, the working status indication of the LCD screen of the control panel changes from “STOP” to “WORK”, the device capacitor is charged, and the charging process can be seen from the LCD screen in front of the device.

(4) Put the battery module to be tested on the PV module tester and ensure that the alligator clips are in good contact with the positive and negative poles of the module (red is the positive pole, the positive pole of the component to be measured; black is the negative pole, and the negative pole of the component to be measured).

(5) Click the “Test” button with the mouse to test. After the test, you can see the test results and curves on the screen.

(6) Parameter adjustment. In the main interface of the software, select the “parameter setting” menu or press the F4 key to enter the “battery parameter” interface as shown in Figure 7-1-7.
First click the “Add” button in the “Battery Type” entry to add a battery type according to the actual application, or you can select an existing battery type to change it. “Battery type name” can be input arbitrarily, “Battery area” should be input according to the actual cell area, and click the “Apply” button to take effect. Click the Quick Settings button or press the F2 key on your keyboard to access General Controls.

Select the battery type just added or changed in “Battery Specification Selection”. After confirming the battery type, return to the “Battery Parameter Interface” again, and the parameter adjustment operations are as follows:

(1) Clear all parameters to zero first.
①Clear the current correction coefficient setting. Click the “Parameter Settings” button and select “Battery Parameters”. Fill in “0” in the “Current Correction Target” dialog box, click the “Calculate” button, the current correction coefficient will become “1”, and then click the “Apply” button to confirm the modification.
②Clear the voltage correction coefficient setting. Fill in “0” in the “Voltage Correction Target” dialog box, click the “Calculate” button, the voltage correction coefficient will become “1”, and then click the “Apply” button to confirm the modification.
③Clear the curve correction coefficient setting. Fill in “0” in the “Curve Correction Coefficient” dialog box, click the “Apply” button, and finally click the “OK” button.

(2) Select “Main Interface” or press Fl key to test. Observe the test results.

3) Go back to the “parameter setting” menu, enter the short-circuit current and open-circuit voltage values ​​of the standard PV modules and calculate them according to the parameters of the standard modules.
Enter the short-circuit current value of the standard battery assembly into the “Current Correction Target” dialog box, click the “Calculate” button and click “Apply” to correct the short-circuit current.
Enter the open circuit voltage value of the standard battery pack into the “Voltage Correction Target” dialog box, click the “Calculate” button and click “Apply” to correct the open circuit voltage.

(4) Select “Main World” to test and observe the test results. If there is an error between the “maximum power” measured at this time and the “maximum power” of the standard component, perform the following operation (5). If not, proceed directly to operation (6).

(5) Enter the value of “Curve Correction Coefficient” in the “Curve Correction” dialog box. The value entered in the curve correction factor can be used to fine-tune the maximum power tested. This value is based on “0”, the larger the value, the higher the power, and the smaller the value, the lower the power.

(6) Set the light intensity to 100mW/cm². Click the “Parameter Settings” button and select “Battery Parameters”. Enter a value in “Light Intensity Correction Factor” so that the measured light intensity is 100mW/cm². The larger the value, the higher the light intensity, and the smaller the value, the lower the light intensity.

(7) The parameter adjustment ends.

What is a PV module tester?
PV Module Tester Operation

3. Precautions for PV Module Tester
Photovoltaic module tester is a precision device for the characterization of the electrical performance of photovoltaic modules. In order to ensure the accuracy of the test data of the device, the following matters must be paid attention to during the operation.

(1) Ensure that the equipment works under the conditions of constant temperature of 25℃±5℃ and humidity of less than 90%RH.

(2) Ensure that the indoor light is constant.

(3) When the equipment is not used for a long time, the voltage on the control panel should be reduced to 0.

(4) In order not to affect the test results, regularly clean the table with anhydrous alcohol.

(5) The set parameters cannot be adjusted at will.

(6) It is strictly forbidden to test the equipment empty to prevent short circuit.

(7) Non-operators are prohibited from opening the equipment.

(8) It is forbidden to insert external U disks, CDs, etc. into the computer to prevent viruses in the computer. It is recommended to install anti-virus software and check regularly.

(9) Before turning off the power of the device, make sure that the voltage on the control panel drops to within 10V to avoid damage to the device circuit.

(10) The equipment should be re-calibrated at least once every 24 hours of use.

(11) The voltage on the control panel has been set at the factory, and it is strictly forbidden for non-professionals to adjust it (important).

In addition, the daily maintenance and maintenance of the photovoltaic module tester must also be done.

(1) Before the test every day, use a soft cloth to clean the dust on the glass table and other fish clips.

(2) Regularly clean the glass countertops and fish clips with anhydrous alcohol.

(3) When replacing the argon lamp, please wear gloves to prevent fingerprints from contaminating the surface of the jaw lamp.