Kā izmantot multimetru, lai atrastu noplūdes strāvu?
Noplūdes mērījums galvenokārt ir paredzēts, lai noteiktu, vai strāvas vads, neitrālais vads un siena ir labi izolēti un vai strāvas vads (strāvas vads, neitrālais vads) ir labi izolēts no elektrisko ierīču, piemēram, ledusskapju, indukcijas plīšu, metāla korpusa. , mikroviļņu krāsnis, elektriskās tējkannas un citi metāla korpusi.
1. Under normal circumstances, the surface of the live wire and the neutral wire is well insulated, and the resistance between the wire and the wall is generally more than MΩ, and the minimum should be 0.5MΩ to be considered qualified. Measurement steps: ① Cut off the main power switch to ensure that the power supply is disconnected; ② Use a multimeter to measure the 20MΩ ohm range; ③ Connect one test lead to the wall, and measure the impedance between it and the wall with the other test lead live wire and neutral wire. If it is less than 0.5MΩ, it means that the wire has leakage, it may be because the wire is worn or the connection is not well wrapped, etc. It is best to check the line.
2. The principle of measuring whether the metal casing of electrical appliances is leaking is similar. Use a multimeter to measure the 20MΩ ohm range when the power is off. One test lead is connected to the casing, and the other test lead is connected to the power line (live wire, neutral wire) to measure its impedance. Under normal circumstances, it should be more than 0.5MΩ , if the impedance is small, there is a leakage phenomenon.
