Inverter maintenance problem set as the output side of the electromagnetic contactor, what precautions ① Do not run off again pull, will have a huge impact because current. It is sometimes the drive may trip. ② momentary power failure occurs, the inverter stop. Due to the instantaneous electrical power failure occurs very short period of time (0.1 seconds) when 6se70 maintenance inverter, the contactor disconnects and the drive does not appear undervoltage alarm. Therefore, in the resumption of power generation inrush current, the inverter may overcurrent trip. Drive repair entry - When Protecting the basic performance characteristics of siemens with varistors (1) repair the drive, when the impact of the strong impact of the source (or inrush current Isp = Usp / Zs) does not exceed a predetermined value, the varistor limit voltage must not exceed the protected object can withstand impact resistance voltage (Urp). (2) impact resistance maintenance inverter, namely the varistor itself should be able to withstand the impact of current, the impact energy, and several attacks have appeared when the average power. (3) Life features are two, one is the continuous operating voltage of life, namely the varistor predetermined ambient temperature and system voltage conditions should be able to work reliably specified time (hours). Second, the impact of life, that can reliably withstand the impact of the number of times specified. (4) Varistor intervention system, in addition to play a protective role 'safety valve', it will also bring some additional impact of domestic maintenance inverter, which is called 'secondary effects', it should not reduce the normal system performance. Then there are factors to consider three, one varistor itself capacitance (tens to tens of thousands PF), the second is in the system voltage leakage current, three are non-linear current source impedance by varistor coupling effect on other circuits. Maintenance inverter igbt, maintenance inverter, electrical heavy on the people by the Shenyang Electric Limited. Shenyang Electric Co. on people (www.zsmsy.com) strong, credible, and other industries in other Shenyang, Liaoning province has accumulated a large number of loyal customers. The company better work attitude and constantly improve the innovative ideas will lead sink into the brilliant electric and you work for a better future!