A digital multimeter is an electronic instrument used for electrical measurements. It can have many special functions, but its main functions are measuring voltage, resistance, and current. As a modern multipurpose electronic measuring instrument, it is primarily used in the fields of physics, electricity, and electronics.
In daily life, you may encounter situations where household appliances leak electricity without realizing it, which can be quite dangerous!
We can use a digital multimeter to measure whether there is leakage. Use the continuity setting of the multimeter to measure the ground and the part of the circuit being measured. If the meter shows a resistance value, it indicates that there is no insulation. However, in reality, a megohmmeter should be used to measure leakage. This is because the voltage across the probes of the multimeter during measurement is very low, generally not exceeding 9V, which cannot penetrate the gap for leakage. A megohmmeter can reach over 1000V. Insert the multimeter leads into the corresponding terminals for measuring AC voltage, then use one probe to measure the neutral line or ground line, while using the other probe to measure the suspected leakage area. Check the reading on the multimeter; if it is 0, it indicates no leakage and no voltage! If it shows 220 or any voltage exceeding 36V, it indicates leakage, meaning it is unsafe!
Use the resistance setting of the multimeter on the 200M scale to measure insulation resistance, first determine which wire is leaking or which two wires are shorted.
The method is as follows:
Measure the insulation resistance between the live wire and the neutral wire, measure the insulation resistance between the live wire and the ground wire, and measure the insulation resistance between the neutral wire and the ground wire. If there is a short circuit, the insulation resistance will be close to zero. Knowing which wire is leaking, use a segment search method to gradually narrow down the fault range. Alternatively, use an elimination method by separating the lines and conducting power tests section by section.
If you find this useful,
please follow and share our article!
Teacher Li 180 7312 7718
Teacher Li 189 0079 3946
Teacher Liu 133 4869 6575
Teacher Liu 177 0844 2926
Teacher Chen 186 2757 3582
Teacher Wang 186 8498 4659
Teacher Lang 155 7515 0051
Shuguang Education offers
FREE SERVICES
————————
Pre-exam Theory Review Guidance
On-site Simulation Practice
Note: This service is only available during normal working hours on weekdays.
Shuguang Education Special Industry Certification
Electrical Work
High Voltage Electrician Low Voltage Electrician Power Cable Relay Protection Electrical Testing
Welding Work
Melting Welding and Thermal Cutting
High-altitude Operations
High-altitude Installation, Maintenance, and Dismantling Operations
Refrigeration and Air Conditioning Work
Installation and Repair of Refrigeration and Air Conditioning Equipment Operation of Refrigeration and Air Conditioning Equipment
Safety Officer
Enterprise Production Safety Officer
