In the transformation of the two networks, a large number of residual current action leakage protector has been used. Several years have passed, it has been proved that the leakage protector is damaged and manually removed from the operation phenomenon is very serious.The problem of power consumption, the problem of safe power consumption is still serious.The causes are various, but the direct cause is the frequency of the leakage protector, refuse to move, seriously affect the normal electricity use, make the pipe, electricity personnel to leakage protector lose confidence, or even give up.

The frequency of leakage protection, including two aspects: leakage protection is the first is the grid does have grounding, leakage protection normal operation.In this kind of normal action, because of the aging of the power grid, climate and environmental change, the action caused by the grid grounding point accounted for the majority, and the action caused by electric shock is very few.It can be imagined that to be able to use electricity normally is the first demand of people, in order to prevent the occurrence of personal electric shock injury with a very low probability and incur frequent power cuts, affecting normal production and life will certainly cause people's troubles.

The grid did not have grounding originally, but the leakage protector may produce misoperation under the following circumstances:

1. Since the action of the leakage protector is triggered by the signal, the action of the leakage protector will also be triggered by the signal under other electromagnetic interference, resulting in misoperation.

2. When the power switch is closed for power transmission, shock signals will be generated, resulting in the wrong operation of the leakage protector.

3. The sum of multiple branch leakage can cause misoperation.

4. Repeated grounding of neutral wire may cause misoperation of serial current.

It can be seen that due to the possibility of misoperation of leakage protector in technology, the frequency operation of leakage protector becomes more serious and complex.From the technical principle analysis, the leakage protector also has the possibility to produce the rejection movement the technical erroneous zone.

1. When the neutral line is repeatedly grounded, it will cause shunt rejection of the leakage protector, and it is difficult to find the neutral line repeated grounding site.

2. When the power supply is out of phase, which happens to be the working power supply of the leakage protector, the resistance will occur.

From the above analysis, it can be seen that the frequency movement and resistance movement of the leakage protector in practical use are caused by both objective environment and management reasons, as well as the technical errors of the leakage protector itself.In particular, the use of leakage protector requires that the neutral point of the grid must be grounded, and the technical errors of the leakage protector are mostly related to the grid neutral point grounding:

First, because the neutral point is grounded, the support of the phase line of the power grid bears the phase voltage all year round, so the support is broken down, forming the grid connection point, causing leakage, causing the frequency movement of the leakage protector.

Second, due to the neutral point grounding, when the phase line occasionally grounding, will immediately produce a large leakage current, not only increase the electrical loss, easy to cause fire, but also aggravate the frequency of leakage protector.

Third, because the neutral point is grounded, when the person gets an electric shock, it will immediately produce a very large electric shock flow, the threat to people's life is very big, even if there is a leakage protector is the first shock, and then action protection, if the action is slow or malfunction, the consequences will be more serious.

Fourth, since the neutral point is grounded, the distributed capacitance of the grid to the ground is connected in the loop, which will increase the shock current to the ground when the switch closes, resulting in misoperation.

Fifth, because the neutral point has been grounded, the repeated grounding of the neutral line is difficult to be found, and the repeated grounding of the neutral line will cause shunt rejection and misoperation of the leakage protector.

It can be seen that there are technical errors in the leakage protector, and these technical errors are closely related to the grid neutral point grounding, and the use of the leakage protector, the grid neutral point has to be grounded, so in the leakage protector's technical ideas to solve the problem of frequency, refuse to move is unlikely.

Two points need to be noted:

1. When single-phase electric shock accident occurs (this kind of accident has the highest probability in electric shock accident), that is, when the load side of the leakage protector contacts a phase line (fire line), it can play a very good protective effect.If the human body to the ground insulation, this time touching a phase line a zero line, leakage protector can not play a protective role.

2. As the role of leakage protector is to prevent problems in the future, when the circuit works normally, it can not reflect its importance, often not easy to attract people's attention.Some people in the leakage protector action is not carefully to find the cause, but the leakage protector short connection or removal, which is extremely dangerous, is absolutely not allowed.