General installation environment requirements of frequency converter: ambient temperature -5℃-40℃. A large number of studies show that the failure rate of inverter increases exponentially with the increase of temperature, and the service life decreases exponentially with the increase of temperature. If the ambient temperature increases by 10℃, the service life of inverter will be halved.
In addition, whether the inverter runs well or not has a great relationship with the cleanliness of the environment. Summer is the frequent period of inverter failures, and only through good maintenance can we reduce the occurrence of equipment failures. Please pay attention to it.
When maintaining the high-voltage inverter in summer, attention should be paid to the temperature of the installation environment of the inverter, and the dust inside the inverter should be cleaned regularly to ensure the smooth cooling air path. Strengthen inspection and improve the surrounding environment of frequency converter, motor and line. Check whether the terminal is fastened, ensure the correct and reliable connection of each electrical circuit, and prevent unnecessary shutdown accidents.
I. Matters needing attention in daily inspection
1. Carefully monitor and record the display parameters on the man-machine interface of the frequency converter, and report any abnormality immediately.
2. Carefully monitor and record the ambient temperature of the frequency conversion room, which should be between-5℃ and 40℃. The temperature rise of phase-shifting transformer should not exceed 130℃.
3. When the temperature is high in summer, the ventilation and heat dissipation of the inverter installation site should be strengthened. Ensure that the surrounding air does not contain excessive dust, acid, salt, corrosive and explosive gases.
4. Summer is a rainy season, so rain should be prevented from entering the inverter (for example, rain enters along the wind outlet).
5. The filter screen on the inverter cabinet door should usually be cleaned once a week; If the working environment is dusty, the cleaning interval should be shortened according to the actual situation.
6. During the normal operation of the frequency converter, a piece of A4 paper with standard thickness should be firmly adsorbed on the filter screen at the air inlet of the cupboard door.
7, frequency conversion room must be kept clean and tidy, should be cleaned at any time according to the actual situation.
8. The ventilation and lighting of the frequency conversion room must be good, and the ventilation and cooling equipment (air conditioner, ventilation fan, etc.) can operate normally.
Second, the need to maintain the project after downtime
1. Clean the inside and outside of the inverter cabinet with a vacuum cleaner with a plastic suction nozzle to ensure that there is no excessive dust around the equipment.
2. Check the ventilation and lighting equipment in the frequency conversion room to ensure that the ventilation equipment can operate normally.
3, check the connection between the cables inside the inverter should be correct and reliable.
4, check the inverter cabinet all grounding should be reliable, grounding point without rust.
5, every six months (within) should tighten the connecting nuts of the internal cable of the inverter again.
6. When the frequency converter resumes operation after a long downtime, the insulation of the frequency converter (including the phase-shifting transformer and the main circuit of the bypass cabinet) shall be measured, and a 2500V megohmmeter shall be used. Only after the insulation test is qualified can the frequency converter be started.
7, check the tightness of all electrical connections, check whether there are abnormal discharge traces in each circuit, whether there is a strange smell, discoloration, cracks, damage and other phenomena.
8. After each maintenance of the frequency converter, carefully check whether there are any missing screws and wires, etc., to prevent short-circuit accidents of the frequency converter caused by small metal objects. In particular, after making great changes to the electrical circuit, ensure the correct and reliable connection of the electrical connecting wires, and prevent the occurrence of "reverse power transmission" accidents.