LCR-T4 component tester

[JJM]

Does anyone know if these cheap component testers can damage an electrolytic capacitor by reverse charging ?

 

[Superduper]

No, these testers don't care about polarity. As these are "smart" testers, the microprocessor almost certainly tests the device in both directions otherwise there would be no way for a tester to identify a diode or transistor or the lead pinout. Electrolytic caps tested with these types of testers generally measure the same readings regardless of how you connect them. They are good for identifying unknown components such as whether a 3 pin device is a PNP or NPN transistor, SCR, dual diode module, or whether an unknown radial (or even smd) device is a resistor, cap, or diode. I would not trust the accuracy of the results however. In short, these are good for hobby use in identifying component types, not so good for precise value measurements. If you really want to test caps and get accurate results, get a dedicated LCR meter. You get what you pay for. If $15 can buy you an accurate test instrument, there would be no market for a Fluke or Agilent instrument costing thousands (or tens of thousands).