Common faults of low voltage switchgear

As we all know, the low-voltage switchgear has GCS, GCK and MNS, which belong to the low-voltage extraction switchgear. After being used for a long time, there will be some difficult problems and common faults. Today, I will tell you about the difficult problems of the low-voltage drawout switchgear.

1. Common failures of primary and secondary plug connectors

The most common problem with withdrawable switchgear shell is the common failure of the plug connector. And the key reason for the common failure of the plug connection head is bad contact phenomenon. Poor contact of the first plug connector leads to overtemperature of the connection head, burn the surrounding insulation layer material of outdoor switchgear, produce the shell or two color short circuit fault; The secondary plug connection head contact phenomenon, will make failure of the precise measurement.

The reason for the bad contact of the plug connector is that the precision of the installation of the power plug and socket is insufficient, and the error is too large, and then the bad contact and hot phenomenon are more serious. Although some power plugs and power sockets are accurate, they are not inserted into the deep layer, and the total area of the touch is insufficient, which leads to the expansion of the resistor at the touch area and burning hot. The misalignment of the secondary power plug also often occurs. There are generally 20 pairs of secondary plug connectors. Be sure to plug each butt carefully.

As for the first and second plug connecting head and matching power socket, we should ensure a certain mechanical equipment service life.

2. The natural ventilation in the low voltage switchgear services is poor, and the working temperature in the control and switchgear is too high, which endangers the insulation layer and the service life

At this stage, the waterproof level of the low-voltage distribution switchgear that the customer stipulates is getting higher and higher, and the waterproof level of IP40 has become the lowest level. Generally, as for high voltage switchgear used in the room, IP20 or IP30 waterproof rating will do.

If you choose IP40 waterproof level, be sure to add natural ventilation heat exhaust.

3. Lack of compressive strength of control and switchgear body

In some cases, the compression strength problem of the low voltage switchgear cabinet body is highlighted. If there is a three-phase five-wire switchgear, the vertical main bus groove is double 120mm×11mm grounding copper bar, and the bus groove support frame uses 40mm× 20mm aluminum profile containing the standard displacement coefficient perforation. Here on the support frame, only the 50mm diameter pillar insulator is installed, and the fixed anchor bolt corresponding to the composite insulator is only M10 type. In that case, it has already been deformed without experiencing short circuit. Therefore, it is only possible to replace the 50 mm ×5 mm stainless steel plate "C" aluminum profile and increase the pillar insulator diameter. When the bus groove support frame interval is more than 0.8 meters, the bus groove insulation layer should be added in the middle. Metal was chosen to better reduce eddy current effects. Support insulators with high aspect ratio are selected so that the bus groove does not have to be too close to the level support.

Above is the common failure of low-voltage control and switchgear services for everyone, hoping that it can help you.