When your electrical appliances fail to function after they have been plugged into a particular socket, it’s likely that the outlet is faulty. The problem could be that the outlet is not well grounded or that the voltage is not flowing through it properly.
With the best multimeter/best digital multimeter, you can diagnose such problems on your own without having to call an electrical technician for help. But before you do that, it’s important that you first factor in your own security.
For a start, don’t attempt to diagnose the outlet when there are kids or pets around because their clumsiness can be messy. In addition to that, you should wear shoes and gloves to protect yourself against stray current. Here is a list of steps that you should follow when testing an outlet with a multimeter.
Identify the Outlet to be Tested
You obviously have more than one electrical outlet in your home. Since all of them can’t be faulty at the same time, it’s advisable that you select the one that’s not functioning. If there are things in front of the outlet such as drawers and coaches, you should remove them so that you can have more space when carrying out the test.
The next thing is to identify the terminals of the outlet. Although outlets come in different designs, they usually have three terminals. The hole on the left hand side is the neutral terminal. The hole that’s on the right hand side is the positive terminal or the one that holds the live wire. There is another hole that’s located just below the live and negative polarity terminals. The hole is reserved for the earth terminal.
Switch to AC Voltage
A multimeter can be used for testing voltage (AC and DC), resistance, temperature and decibels. If the device is not set to measure voltage, you will definitely get the wrong readings that can mislead you. You should therefore ensure that you have configured the multimeter to voltage mode before getting started.
Connecting the Leads
Every multimeter comes with two leads; black and red in color. The colors are used to determine where each lead should be connected. The black lead is supposed to be attached to the connector that has a minus sign while the red lead goes into the terminal that has a positive sign.
To establish whether there is current inside a socket, you should insert the black lead into the hole on your left hand side and the positive lead into the hole on the right hand side. Depending on your geographic location, the voltage should range between 110 and 120 or 220 to 240. If the display of the multimeter doesn’t show anything, the wiring of the socket could be faulty or the socket needs to be replaced because it’s dead.
Check for Earthing
Every outlet has a ground terminal that’s reserved for absorbing excess current. If a socket is not earthed, you might get electrical shocks when you touch an appliance that’s connected to the outlet.
To get started, simply put the red lead into the positive terminal that’s located on the right hand side and then insert the black lead into the ground hole. If you get a negative reading, it means that grounding was done the wrong way or the wires are reversed.