1. In order to use and communicate with the reliability of AC variable frequency power supply and prevent other disturbances, it is necessary to use independent grounding, and the grounding resistance is less than 1. All the I-o communication interfaces and other grounding wires of the communication variable frequency power supply should be independently connected with the grounding wires of the corresponding system.
2. Correct wiring and voltage frequency setting.
1) It is necessary to read the operation manual carefully and grasp its application, precautions and wiring methods before the equipment and operation communication of the variable frequency power supply.
2) After the equipment is well equipped according to the technical conditions required by the equipment, the voltage and frequency should be correctly set according to its own application requirements to prevent the damage of the back-end load due to the incorrect setting of voltage and frequency.
3. In order to prevent damage to the power supply in the actual use of AC variable frequency power supply, the following 6 points should be noted:
1) The communication frequency conversion power supply and the starting motor should not be directly equipped to communicate with the contactor (excessive voltage and short-circuit current will occur when the contactor is damaged).
2) The output back end of the AC variable frequency power supply should not be equipped with capacitance compensation equipment (a.).Prevent damage to the capacitor caused by higher harmonics or bProtection against overcurrent and malfunction of the power supply).
3) Prevent the use of communication variable frequency power supply to start the motor or other loads (harmonics in the current that do not match the power supply capacity to adversely affect the system of the variable frequency power supply. When using AC variable frequency power supply to drive multiple motor loads, in addition to considering that the total current of the motor running is less than the rated current, the influence of the max starting current of the motor should also be considered).
4) The length of the configuration cable should be shortened as much as possible between the AC variable frequency power supply and the back-end load in accordance with the standard specifications (reduce the cable dispersion between the two to reduce the occurrence of parasitic current).
5) It is necessary to convert 50Hz power frequency output and 60Hz frequency conversion output firmly (if the AC frequency conversion power supply is assumed to work in the mode of power frequency and frequency conversion, it is necessary to have a good coordination between the order and time of power frequency and frequency conversion).
6) The input and output of the communication variable frequency power supply are equipped with filters (which can be useful to reduce the harmonic disturbance of the communication variable frequency power supply to the power grid and related electrical equipment in the power grid and reduce the harmonic disturbance of other loads at the back end) If the conditions permit, the input end of the communication variable frequency power supply is equipped with a reactor to improve the power factor, reduce the harmonic disturbance, and reduce the energy consumption to achieve the purpose of saving the cost.