Troubleshooting and solving six common problems of

Check and solve 6 common problems of leakage protector tripping

leakage protector is different from circuit breaker and disconnector. In addition to the function of opening and closing circuit, the circuit breaker also has the function of short-circuit protection. The disconnector has only the function of opening and closing circuit. In addition to the function of opening and closing the circuit and short-circuit protection, the leakage protector also has the function of leakage protection (the leakage current ranges from 30mA to 500mA)

TN-C-S system is often used in building power supply and distribution system. Generally, two-stage leakage protection is set, and the test result is very different from the actual value. The first level is set at the main switch at the entrance of the power supply, that is, the main switch at the entrance of the power supply selects the leakage switch of level 4 (L1, L2, L3 and N lines) with the leakage current value of 300ma-500ma; The second level is set in the socket circuit in the user's switch box (the leakage switch is not allowed for the suspension air conditioning circuit), and the leakage switch of level 2 (L1 or L2 or L3 and N lines) with the leakage current value of 30mA is selected. Thus, the occurrence of electric shock accidents of power users is prevented and the reliability of safe operation of building power supply and distribution system is improved

after the leakage protection switch trips due to fault, the leakage current detection link of the leakage protection switch must not be removed. According to the fault tripping phenomenon, analyze the cause of fault tripping and find out the solution to the fault. There are roughly six kinds of leakage switch fault tripping phenomenon:

the first kind is that the insulation of the electrical equipment itself is damaged, resulting in the leakage switch fault tripping phenomenon when using electricity

the second kind, the wet insulation strength of the line decreases, resulting in the leakage switch fault tripping phenomenon when not using electricity

the third kind, personal accidental electric shock, resulting in leakage switch fault tripping phenomenon

in the 4th, 5th and 6th categories, the wiring is incorrect during construction and installation, resulting in leakage switch fault tripping during power utilization

the detailed analysis is as follows ↓↓ ↓

type 1: the insulation of the electrical equipment itself is damaged and leakage occurs (the N line in the equipment is short circuited with the PE line). As shown in Figure 1

fault phenomenon: when the socket circuit is powered, the leakage switch of the socket circuit trips

fault cause: after analysis, the line wiring is correct, so it is judged that the insulation of the electrical equipment itself is damaged and leakage occurs (the N line and PE line in the equipment are short circuited)

solution: replace or repair electrical equipment

type 2: the wet insulation strength of the line decreases. As shown in Figure 1, stop the machine immediately after the sample is broken

current

fault phenomenon: when power is not used, the main leakage switch or socket circuit leakage switch in al1 also trips

fault cause: after analysis, the wet insulation strength of the line is reduced, resulting in the leakage current exceeding the allowable leakage current value of the leakage switch. It may also be caused by short circuit

solution: dry the circuit and improve the insulation strength. Check if the circuit is caused by a short circuit, and eliminate the short circuit fault

type 3: someone gets an electric shock, and the main leakage switch or socket circuit leakage switch in al1 trips. As shown in Figure 1

fault phenomenon: the main leakage switch or socket circuit leakage switch in al1 trips

fault cause: someone got an electric shock

solution: strengthen the nationwide education on electricity safety to avoid electric shock accidents

type 4: the wiring is incorrect during construction and installation, and the N line is connected to the PE line in the lighting circuit. As shown in Figure 2

fault phenomenon: the socket circuit can use electricity normally. When the lighting circuit uses electricity, the main leakage switch in al1 trips

fault cause: after analysis, the wiring during construction and installation is wrong and incorrect. The N line in the lighting circuit was connected to the PE line by mistake

solution: change the PE line in the lighting circuit to the N line

type 5: the wiring is incorrect during construction and installation, and the N line and PE line in the socket box are connected incorrectly. As shown in Figure 3

fault phenomenon: the lighting circuit can use electricity normally. When the socket circuit uses electricity, the socket leakage switch in aly trips, and sometimes the main leakage switch in al1 also trips

fault cause: after analysis, the wiring during construction and installation is wrong and incorrect. The N line and PE line in the socket box are connected incorrectly

solution: exchange the N line and PE line in the socket box

type 6: the wiring is incorrect during construction and installation, and the N line and PE line are mixed in al1 box. As shown in Figure 4

fault phenomenon: when the socket circuit or lighting circuit is powered, the main leakage switch in al1 trips

fault cause: after analysis, the wiring during construction and installation is wrong and incorrect. Mix the N line and PE line in al1 box

solution: at the load end of the main leakage switch of al1 box, move the lower piston rod down and exchange the N line and PE line