1. Phenomenon: Overcurrent (OC): It is the most frequent phenomenon of inverter alarm. (1) When restarting, it will trip at a speed. This is a very serious overcurrent phenomenon. The main reasons are: load short circuit, mechanical parts are stuck; inverter module is damaged; motor torque is too small and so on. (2) Jumping on power-on, this phenomenon can't be reset generally. The main reasons are: bad module, bad drive circuit, and bad current detection circuit. (3) When restarting, it does not immediately trip but during acceleration. The main reasons are: the acceleration time setting is too short, the current upper limit setting is too small, and the torque compensation (V/F) setting is high. 2. Example: A LG-IS3-43.7kW inverter will jump “OC†as soon as it starts up. Analysis and Maintenance: Open the cover no sign of burn out, on-line measurement IGBT (7MBR25NF-120) is determined substantially no problem for high-power transistors opening and closing off a further judgment, after the measuring means 7 are detached IGBT well. 3, troubleshooting: when the half-bridge driver circuit in the measurement along with the other two found a significant difference between the way, after careful examination revealed an optocoupler A3120 output pin and the negative power supply circuit, substantially the same three-way replacement. Module fitted with a power run everything. Incremental Encoder,Linear Scale Encoder,Dual Concentric Rotary Encoder,Dc Servo Motor Encoder Yuheng Optics Co., Ltd.(Changchun) , https://www.yhenoptics.com
Causes and treatment methods of inverter overcurrent fault
The use of frequency converters can greatly reduce the energy consumption. Therefore, the inverters are used in large and small equipments. The inverter runs through the entire power plant. The safe operation of the inverter becomes a key link of the power plant. Once the inverter has problems, it will lead to large equipment. Damage or even explosion, the safe operation of a crisis power plant, brings incalculable economic losses to the power plant. It can be seen that the power industry personnel, especially the power plant staff, have a little knowledge of the inverter fault and the analysis of the cause of the fault, and can detect the running status of the inverter in the first time, which is an urgent task.