Common fault maintenance and maintenance precautions for power distribution cabinets

Distribution cabinet common fault maintenance and maintenance precautions The distribution box is also called the distribution cabinet, which is the general name of the motor control center. The distribution box is to assemble the switchgear, measuring instruments, protective appliances and auxiliary equipment in a closed or semi-enclosed metal cabinet or screen according to the requirements of electrical wiring, forming a low-voltage power distribution device. The distribution box has the characteristics of small size, easy installation, special technical performance, fixed position, configuration function, not limited by site, relatively common application, stable operation, high space utilization, less land occupation and environmental protection effect.

Distribution cabinet maintenance

1. The circuit breaker cannot be closed 1. Press the closing button, and the closing coil is electric but does not operate – replace the undervoltage coil; 2. Poor contact of the closing button – replace the closing button; 3. The melt core (insurance) of the control loop burns out – replace the melt core; 4. There is no energy storage in the circuit breaker – check that the motor voltage must be greater than 85%; 5. The voltage of the closing solenoid is too small – the voltage of the closing solenoid must be greater than 85%; 6. Closing solenoid is damaged – replace the closing solenoid; 7. Poor contact of the secondary circuit of the drawer circuit breaker – shake out the drawer circuit breaker, and then shake it back to the connected position to check whether the secondary circuit is connected reliably; 8. The 10,000-turn switch is in the stop position – turn the switch to the power transmission position.

2. The main switch of the incoming cabinet cannot be opened1, and the opening button is in poor contact – replace the opening button; 2. The opening coil burns out – replace the opening coil.

3. The main metering reactive power meter reverses or does not rotate 1, the power factor of capacitance compensation is high – adjust the capacitance compensation to 0.92-0.97; 2. The phase sequence of the transformer incoming line is wrong – readjust the phase sequence; 3. The voltage and current circuit is normal – replace the reactive power meter.

Fourth, the capacitor cabinet can not be automatically switched 1, the current sampling signal line is not connected – connect the current sampling signal line; 2. Compensate for the burning out of the melt core of the controller – replace the melt core; 3. The voltage is high, and the controller displays overvoltage – adjust the overvoltage protection point; 4. The current is small, and the controller display is ahead – it can work automatically after increasing the current; 5. The capacitor cabinet compensator shows overvoltage – re-set the voltage value.

Fifth, the drawer outlet line electric energy meter does not rotate 1, the secondary plug-in contact is poor – readjust the secondary plug-in contact piece; 2. The current and voltage are normal – replace the electric energy meter.