Six taboos for inverter control circuit wiring

Six taboos for inverter control circuit wiring

 Although the inverter auxiliary control method has many advantages, if the control circuit wiring is unreasonable, it will often bring adverse effects to the normal operation of the inverter, and even cause unnecessary faults. Today, based on my own work experience, I summarized six taboos regarding the wiring of the inverter control loop:

 1. The wiring of the inverter control circuit should be separated from the main circuit cable (power line), so as to avoid the harmonic interference component in the inverter main circuit from polluting the inverter control circuit; 2. The fault signal and multi-function of the inverter Terminals such as contact output signals may drive high-voltage AC contactors/relays. When used, separate the wiring from the terminals or contacts of other control circuits to avoid high-voltage breakdown at the fault point.

 3. In order to prevent misoperation caused by interference signals, when wiring the low-power control circuit of the inverter (such as the wires used by the sensor under the PID control function, etc.), you should choose a shielded wire or twisted wire with strong anti-interference ability;

 4. For the wire length of the inverter control loop, 50m is the reference base point (in some cases, the value is 100m, which is mainly related to the cross-section of the wire, material, signal strength and other factors). When the wiring distance exceeds this length, you should Use relay circuits or relays to amplify the signal;

 5. When crimping the control circuit wires of the inverter, pay special attention to the polarity of the analog signal to prevent the polarity from being reversed and causing damage to the inverter's auxiliary control electronic circuit;

 6. When the inverter is energized, the digital multimeter with buzzer function file (this file has the highest output voltage than other files) can not be used to measure the on/off of the control circuit to prevent the power in the digital multimeter from being The test leads are conducted to the control terminals of the inverter, causing malfunction!