The MTU diesel generator manufacturers find out how to prevent wet generator sets in wet weather:
1. Drying mode with load:
If the surface is only wet, it can be dried by a load drying method. When dry, the generator set can operate at 50% rated current load. Then increase the rated current by 65%, 85% and 100%. The load is 4 to 5 hours at each stage. The insulation resistance of each winding should be tested regularly during the drying process. After the insulation resistance is satisfied, drying can be stopped and the generator set is usually tested.
2. Cold operation method:
In the case of AVR power line disconnection, the generator set placed in a dusty or humid environment for a long time can be idle for about 10 minutes. This may be sufficient to dry the winding surface and increase the insulation resistance value to more than 1 megohm for power generation. The device can be restored to normal operation.
3. Hot air method:
Remove all cover plates of the generator set to vent damp air. Use a hair dryer to blow through the generator set air intake. Please note that the heat source and windings should be kept at least 300mm to avoid overheating and lead to insulation damage and control the surface temperature of the windings. The winding surface temperature shall not exceed 85°C, the inlet temperature shall not exceed 90°C, continue blowing every half hour and record the insulation resistance value. When this value is greater than the specified value, the drying process is complete. Remove the hair dryer, cover all the LIDS, and try again.
4. Short circuit current drying method:
First of all, the safe operation of the electrical and mechanical equipment of the generator set to ensure the safe operation of the generator set. The output end of the generator set is short-circuited by a short circuit sheet, which shall be able to withstand the rated current of the generator set. Turn off the AVR and switch to the external 0~24V DC power supply. Adjust the DC power supply voltage so that the stator current per phase is 50-70% of the rated current. Stop every 30 minutes, disconnect the external excitation power supply, check and record the insulation resistance value. If the insulation resistance is greater than the specified value, the external DC power supply can be removed and the AVR can be reconnected and retuned. The generator set can operate at rated speed, but the speed should be kept constant to avoid temperature instability.
Jiangsu Meao Power Technology Co., Ltd. focuses on the development and manufacture of diesel generator sets, and has accumulated rich experience in manufacturing and service in this field. As a professional generator manufacturer, MEAOPOWER attaches great importance to product development, innovation and service quality, and maintains close strategic cooperation with famous domestic and international enterprises such as Cummins, Perkins, Doosan, Yuchai, Weichai, Shangchai, Wuxi Wandi, Lillesomer, Stanford, Marathon and so on.
