NVF5 Series User Manual        Chapter 8 Maintenance 
Discriminant criteria: Whether there is liquid leakage, whether the safety valve has 
projected, measurement of the electrostatic capacitance and insulation resistance.   
3.Relay 
Possible damaged reason: Corrosion, frequent action.。 
Discriminant criteria: Opening and closing failure. 
8.6 Storage 
After purchasing the inverter, attention must be paid to the following for temporary and 
long-term storag: 
1.Avoid storing in the hot, humid environment with much dust, metal powder; ensure good 
ventilation; 
2.The inverters which have been stored for more than 2 years must been done precharge 
experiment. When energized, the  voltage  regulator is used to slowly increase the 
voltage to the rated value for nearly five hours without load. 
- 100 -