Introduction to Continuity Measurements
You can use the same connection procedure used in measuring current to verify that a circuit, wire, fuse, or switch is complete without breaks in the circuit. This is called a continuity test, and most DMMs will have an audible continuity setting (). If there is no audible alarm, then the circuit is broken. You can test the audible setting by touching the leads together while the leads are inserted into the common and continuity () jacks. A good example is testing a heating element when you suspect the heating element might be “burned out”. If the heating element is complete without breaks, the audible sound will ring out when tested. However it is important to note that the portion of the circuit to be measured needs to be isolated to ensure a false reading is not obtained. Failure to do so can mean that other parts of the circuit may be read inadvertently thus providing an inaccurate reading.