Photovoltaic module IV tester: Do you understand these common questions?

　　In the production and testing of photovoltaic modules, the IV tester is an indispensable "inspector", which can accurately capture the current and voltage characteristics of the modules and directly reflect the product quality. But many frontline operators may encounter situations where instruments get angry, and in fact, many problems have patterns to follow. Today, let's talk about the most common problems with IV testers to help everyone avoid detours.

　　The most commonly asked question is' The test curve suddenly deforms and deviates significantly from the standard curve ', which is also the most influential issue on the test results. Don't rush to report for repair in this situation, check the stability of the light source first. The IV test has extremely high requirements for the light source. If the xenon lamp of the simulator is used for too long or the reflector is covered with dust, it will cause uneven light intensity, and the curve will naturally show peaks or depressions.

　　The poor repeatability of test data is also a headache inducing problem. Despite being from the same batch of components, the results of several consecutive tests show significant deviations. There may be two reasons behind this: one is poor contact. If the probe of the tester oxidizes and rusts, or if the contact with the component junction box is not tight, it will cause resistance fluctuations and affect data. It is recommended to regularly wipe the probe with alcohol to check if the contact pressure meets the standard. The second is environmental interference. The drastic changes in temperature and humidity in the testing environment will directly affect the electrical performance parameters of the components. So the testing workshop needs to do a good job in temperature and humidity control, and the instruments also need to be preheated in advance to keep themselves in a stable working state.

　　There is also a situation where the instrument does not respond or reports an error after being turned on. In this case, we should first conduct a basic investigation. Firstly, check the power supply circuit to ensure that the plug is securely plugged in and the power supply voltage is stable. Often, this is caused by temporary power outages or loose wiring. If there is no problem with the power supply, then check the heat dissipation of the instrument. Long term high-intensity work will cause the internal temperature of the instrument to become too high, triggering overheating protection. At this point, simply turn off the instrument, wait for about 30 minutes for it to dissipate heat, and then restart it. If the error persists, you can refer to the error code instructions in the instrument manual to troubleshoot sensor or motherboard issues.

　　Many people are still confused that 'test results are always lower than theoretical values'. This may be caused not only by quality issues with the components themselves, but also by expired instrument calibration. The IV tester needs to be calibrated regularly with standard components. If it is not calibrated for a long time, the measurement accuracy will decrease. In addition, the ambient light during testing can also have an impact, even indoors, strong direct sunlight can interfere with the test, so it is best to operate in a dark environment.

　　In fact, many problems with IV testers are related to daily maintenance and operating standards. Regular cleaning, timely calibration, and standardized operation can not only reduce malfunctions but also ensure the accuracy of test data. If you encounter complex problems that are difficult to solve on your own, it is more reliable to contact the professional technical personnel of the instrument manufacturer in a timely manner than blindly debugging. I hope these practical skills can help everyone better use the IV tester and ensure the quality of photovoltaic modules