Multimeters have an option to measure resistance indicated on their front panels. By switching the dial to the ohms setting and turning the power off to the appliances being measured, the status of a circuit can be determined.Continue Reading
A multimeter tests resistance by sending a small electrical charge through the device and recording the current. If the power is on, it will disrupt the device and blow the fuse of the multimeter. Therefore, remove the battery or unplug the appliance from the wall.
The red lead goes to the port marked "VA" or something similar. The black lead goes to the port labeled "COM". Turn the measurement setting of the multimeter to resistance, which is indicated by the ohms symbol. Many digital multimeters will adjust range, but analog multimeters may have ohm, kiloohm, or even megaohm ranges.
Touch the red lead to the positive terminal, marked with a plus sign or the shorter outlet plug, and touch the black lead to the negative terminal or larger outlet plug. Although current can travel either way, it's best to get into the habit of learning which leads are which. Also, always grip the leads by the plastic or rubber housing, never by the metal tip.
Triacs can be tested with the use of a multimeter. A more advanced way of testing a triac is to perform a circuit test.Full Answer >
To test a circuit breaker using a multimeter, remove the circuit breaker box cover and turn the switch on. Using the multimeter's red prong, touch the screw that connects to the breaker. Touch the grounded box using the black prong. If there's no voltage reading, then the breaker is faulty.Full Answer >
Using a multimeter, insert one of the probes from the multimeter into one of the parallel slots in the 240-volt outlet and insert the other probe into the other parallel slot to test if the outlet is indeed carrying 240 volts. If the voltage does not add up to 240 volts, check the slots individually to see which one is carrying less voltage.Full Answer >
You can troubleshoot electrical problems in your house by using a multimeter to test outlets and by checking for obvious problems. A multimeter is a device that tests voltage, resistance and current along a circuit, enabling you to pinpoint problem spots. If you don't feel comfortable, call an electrician.Full Answer >