In the rainy and humid weather, many leakage faults will occur. In fact, the reason for the leakage can be easily detected by using the multimeter in hand. First of all, you have to have a normal table.
Fault finding analysis
Before analyzing the leakage, we must first look at what is happening, what are the obvious features; secondly, observe the visual point of failure from the surface, and then proceed to the next step.
1. Disconnect the main isolation switch of the power supply line and turn off all the user's power load, such as unplugging the refrigerator and disconnecting the water pump switch.
2. Place the gear of the digital multimeter on the 200M block of the ohm file, one pen on one of the two outlets on the load side, and the other pen touches the wall, preferably touch the ground wire or temporarily Ground wire. After the number displayed on the multimeter is stabilized, the value of the insulation resistance of the main line is read.
If the value of the insulation resistance is less than 0.5 megohm, then there is a problem with the main line. If the insulation resistance is above 0.5 megohm, it can be ruled out that the main line is out of order. Use the same method to measure another wire and check the value to see if there is a problem with the main line.
3. Check the insulation resistance values of the shunt and each electrical appliance, and use the same method to detect one by one until the fault point is found.
1. When using the 200M block of the multimeter ohm block, be careful not to touch the metal part of the test pen by hand during the measurement, which will make the reading inaccurate.
2. When measuring each electrical equipment, be careful to discharge first to prevent the capacitive current in the electrical equipment from injuring people.
This method is a safer way to find fault points in an unpowered state. This method is also suitable for the search of power users and plant leakage, but in the search, not only to disconnect the power supply, but also to disconnect the neutral line to avoid electric shock.
This article tags: elevator elevator safety elevator maintenance elevator maintenance elevator knowledge elevator installation