continuity test on capacitor and inductor.

[prateek3790]

if i have a board which is not powered up basically (initial condition) how they will behave if i check them for continuity test using multi meter. meaning whether the capacitor/inductor will be open or short. i am assuming that the capacitor should be short and inductor should be open.

 

[barry]

It also depends on what's connected to the parts you're testing.

 

[FredCailloux]

First of all, Out Of Circuit capacitor is supposed to be Open and coil is supposed to be Close. A coil is a usually a piece of copper wire wrapped around, hence, should read CLose. Capacitors, when under test will take the charge from your tester and eventually become full at the same potential then the tester leads, not taking anymore current will show just like an Open circuit.

In circuit it is another story. If you test a coil when in a circuit, the most likely reading you will have is a Close circuit. Meaning the current flows through the coil. Usually a coil is low resistance (unless it is made of thousands of turn and usually pretty big, but those tend to be rare and expensive so they are not likely to be seen often). A coil is low resistance whether in a circuit or not. If you read Open on a coil, unsolder and take it out of the circuit and retest.

Capacitors are more tricky. Because they are suppose to be Open the performed test might indicate Close because the test leads current passes somewhere else in your circuit. So a capacitor that indicate Close is not necessarily defective. Then it must be taken out of circuit and tested again. Also, some capacitors are so big that you have to test them for some time before they charge ( 5 or 6 seconds in the case of a 1/2Farad, but that is not so common either).

The best way to test a component is Out Of Circuit. Otherwise you may have to do some more thinking and interpretation with a schematic. Good luck with your testings.