DIY Electronic Test Fixture Projects

Preparation

• 1

  Identify the fixtures you want to test. You may have a wall socket that doesn't work correctly, or maybe a light fitting or switch. All of these fixtures can be tested using an electronic multimeter.

• 2

  Put on a pair of lightweight rubber gloves before testing the fixtures. This prevents you from getting an electric shock if you touch a hot wire, as you need the electricity on to test the fixtures.

• 3

  Turn on the multimeter. Set it to measure voltage using the dial or buttons on the front of the meter. Ensure that you set the voltage on the meter to 120 volts, as this is the voltage of your home electrical supply.

Wall Socket

• 4

  Insert the metal prong on the end of the black wire from the meter into the top hole in the wall socket; this is the ground connection.

• 5

  Insert the metal prong on the end of the red wire into the lower left side hole in the wall socket. This is the hot or live connection.

• 6

  Read the voltage displayed on the meter. It reads between 110 and 120 volts, if the wiring to the wall socket is working, meaning there isn't a problem with the fixture. If there isn't a reading, then there's a problem with the wiring or a fault in the wall socket, so it is sensible to call an electrician.

• 7

  Test other wall sockets you've identified that may have a problem. Use the same method as before.

Light Switch

• 8

  Remove the screws holding the light switch cover in place using a screwdriver. Carefully pull the light switch cover toward you slightly so you can access the terminals in the light switch.

• 9

  Look at the terminals on the back of the light switch. The number of terminals depends on the type of circuit the light switch is connected to. A switch that operates a single light has two terminals: one has a black screw and is always hot, and the other is brass and is only hot when the light switch is turned on . A light switch that operates more than one light, or is connected to more than one light switch, has three terminals. One terminal screw is colored black, and the other two are brass. The black terminal is always hot, and the other two alternate depending on what position the light switch is set to.

• 10

  Place the black prong on a part of the metal casing, as this is ground. Put the red prong on the black terminal. Read the meter. It reads 110 to 120 volts, if electricity is getting to the switch. If there isn't a reading, there is a fault in the wiring, so you need an electrician.

• 11

  Place the red prong on the two brass terminal screws. If there are two terminals choose one; it doesn't matter which one you select. Read the meter. If there is a reading, then electricity is getting through the switch fine. If there isn't a reading, move the switch to the other position. The meter displays the voltage if the switch is working correctly. If it doesn't have a reading, you need to replace the light switch.

• 12

  Repeat the process by putting the red prong on the other terminal, if the switch has more than one brass screw. Read the meter as before. If there is a reading, the switch is fine. If there isn't, then move the switch to the other position and read the meter again. If there still isn't a reading, replace the switch. Replace the switch cover after you have tested the switch.

Light Fixture

• 13

  Turn on the light to check whether it is working. If it is, then there is no need to test further. If it isn't, then turn off the light switch.

• 14

  Remove the bulb and put in a new one. Turn on the light switch again. If it works, then everything is fine. If it doesn't, then leave the switch in the "on" position. Remove the light bulb from the socket again.

• 15

  Remove the light fixture's cover, so you can access the two terminals. Either unscrew the cover using your fingers, or use a screwdriver to remove the screws holding the cover in place and then remove.

• 16

  Look at the two wires connected to the terminals. One is black and is the hot wire when the light switch is turned on. The other is white or gray and is the neutral wire that completes the circuit. Place the black prong on a metal part of the light fixture. Place the red prong on the terminal that the black wire is connected to.

• 17

  Read the meter. If you get a reading, then electricity is getting to the light switch, so the light switch has a fault and needs replacing. If it reads zero, there is a fault in the wiring between the switch and the light fixtures, so you need to have it checked by an electrician.