Proper Cable Maintenance for Diesel Generator Load Operation

For both naturally aspirated and supercharged diesel generators, it is emphasized that the low-load/no-load operation time should be minimized, and the minimum load should not be lower than 25% to 30% of the rated power of the unit (for reference only). Because if the diesel generator set operates under low load for a long time, it will have varying degrees of impact on the unit. For example, the internal parts of the engine body will be thermally deformed, reducing the overall stability of the unit; the crankshaft in the diesel engine may break, leading to the overall scrapping of the diesel engine; more seriously, it will cause intensified wear of moving parts, deterioration of the engine combustion environment, etc., resulting in the consequence of the overhaul period being advanced.

Based on the above understanding of the hazards of diesel generator low load, we need to use diesel generator sets correctly, and the operating load is inseparable from cable output. Therefore, we should correctly maintain the cables when loading the Dingbo Power generator set. The specific points to be achieved are as follows:

1.The purpose of line inspection is to prevent accidents caused by external destructive incidents and cable head defects. Inspections should be carried out in accordance with the specified cycle, and the cycle should be shortened if necessary. If defects are found during inspection, measures should be taken in a timely manner.

2.Preventive voltage testing is an effective measure to identify insulation and detect hidden accidents. The withstand voltage test uses DC voltage, which will not cause damage to good insulation and requires small equipment capacity.

3.Current load measurement. The allowable load of a cable depends on the cross-sectional area of the conductor, the maximum allowable temperature, thermal resistance coefficient, structure, ambient temperature, etc. In principle, cables are not allowed to operate with overload, but they can operate for two hours under 10% overload and one hour under 15% overload. Therefore, overload measurements must be carried out frequently to ensure that the cable operates under safe load.

4.Temperature detection is very important because checking the load alone cannot guarantee no overheating. In practice, it is difficult to match the design value with the actual value, and the actual impact will be more complex than considered in the design.

5.Cable grounding resistance check. Dingbo Power generator set manufacturer recommends measuring the resistance value of the cable metal sheath to the ground once a year, which should not be greater than 2Ω. When one end of the single-core cable metal sheath is grounded, the sheath-to-ground resistance value at the other end should be measured at least once a season. The measurement should be carried out at maximum load, and the voltage to ground should not exceed 65V.

6.Cables should be protected against corrosion, as corroded cables are prone to accidents. Therefore, it is necessary to regularly analyze the laying area to ensure the safety of the cables.

The above content is exclusively written and shared for you by Guangxi Dingbo Power, a professional generator manufacturer, hoping to be helpful to everyone.  If you want get more information, please feel free to send email to [email protected], we will pay highly attention on your question.