Learn to use a multimeter to find faults
Method of checking for short circuits in wires with a multimeter
Short circuit of wires: refers to the connection between the live wire and the zero wire, so we call it a short circuit of wires
To determine whether the live wire and zero wire are short circuited with a multimeter, we need to use the beep gear of the multimeter. In the event of a power outage, we first place the red probe on the live wire and the black probe on the zero wire. If there is a beep sound, it indicates that the live wire and zero wire are connected. If the live wire and zero wire are connected, it indicates that the electrical wire is short circuited. If the multimeter does not respond, it indicates that the electrical wire is not short circuited. If the live wire and zero wire are not connected, it indicates that the electrical wire is not short circuited
Note: To check for a short circuit with a multimeter, first cut off the power and disconnect the live and zero wires from the load
Open circuit in the wire: refers to the fact that the wire is disconnected and there is a breakpoint in the middle of the wire, also known as an open circuit
The multimeter is used to determine whether the wire is open, and the multimeter's beep range is also used. Red and black probes are placed on both ends of the wire. If there is a beep, it indicates that the wire is open. If the multimeter does not respond, it indicates that the wire is open
Note: Use a multimeter to determine if the wire is open, and measure the wire break point
The method of using a multimeter to determine whether a wire is leaking electricity
Electric wire leakage: refers to the connection between the live wire and the ground wire, or the connection between the zero wire and the ground wire, which is called leakage. The connection between the live wire and the ground wire is the leakage of the live wire, and the connection between the zero wire and the ground wire is the leakage of the zero wire
Leakage of household appliances: refers to the connection between the wires of household appliances and the metal casing of the appliances, which is called leakage of household appliances
A multimeter is used to determine whether there is leakage in the wires. We also use the beep range of the multimeter to measure the live wire and ground wire, as well as the zero wire and ground wire using red and black probes. If there is a beep, it indicates leakage. If the multimeter does not respond, it indicates no leakage
A multimeter is used to determine whether a household appliance is leaking electricity. We also use the beep range of the multimeter to place red and black probes on the wires and metal shells of the household appliance. If the multimeter beeps, it indicates leakage. If the multimeter does not respond, it indicates that there is no leakage
Note: When using a multimeter to measure leakage, the first step is to cut off the power. For hidden leakage of wires or household appliances, it is generally not possible to measure with a multimeter, and a megohmmeter should be used to measure it
The methods of measuring short circuits, open circuits, and leakage with a multimeter are basically the same, using the buzzer gear of the multimeter to determine whether there is a short circuit, open circuit, or leakage by measuring the on/off method
