Precautions for Low Load Operation of Diesel Generator Sets

Long term full load operation of diesel generators can not only improve their performance, identify safety hazards, but also avoid major communication accidents. The relevant precautions include the following four aspects:

Preparation before startup. Before turning on or off, be sure to check whether the cooling water or antifreeze in the diesel engine water tank meets the requirements, if it is not fully filled. Pull out the oil dipstick and check for any missing lubricating oil. If the specified "static" scale line is missing, carefully check the relevant parts for any potential faults. If any faults are found, promptly troubleshoot and start the machine.

It is strictly prohibited to start the diesel engine under load. Before starting a diesel engine, it should be noted that the output air switch of the generator must be in the closed state. After the ordinary diesel generator set is started, after 3-5 minutes of idling (about 700 rpm), the winter temperature is low, and the idling time should be appropriately extended for a few minutes. After starting a diesel engine, the first thing to observe is whether the oil pressure is normal and whether there are any abnormal phenomena such as oil or water leakage (under normal circumstances, the oil pressure is above 0.2MPa). If any abnormalities are found, the engine should be immediately shut down for maintenance. If there are no abnormal phenomena, increase the diesel engine speed to 1500 rpm. At this time, the generator displays a frequency of 50HZ and a voltage of 400V. Then, close the output air switch and put it into use. The unit shall not operate without load for a long time. (Due to prolonged no-load operation, the diesel engine's fuel injectors may spray diesel fuel and cause incomplete combustion, resulting in carbon deposits and valve and piston ring leaks.). If it is an automatic generator set, there is no need to run it at idle speed because the automatic generator set is generally equipped with a water heater, which keeps the diesel engine body at around 45Co. After starting, it can be powered normally within 8-15 seconds.

Pay attention to the working state during work. During the operation of the unit, a dedicated person should be on duty to regularly observe a series of faults, especially the changes in important factors such as engine oil pressure, water temperature, oil temperature, voltage, frequency, etc. In addition, it should be noted to have sufficient diesel fuel available. If fuel interruption occurs during operation, it may objectively cause a load shutdown, which may lead to damage to the generator excitation control system and related components.

Prohibit parking with load. Before each stop, gradually cut off the load, then turn off the output air switch of the unit, and finally let the diesel engine run at idle for about 3-5 minutes.

Therefore, Dingbo Company suggests that when using diesel generators, the operating time at low load/no load should be minimized as much as possible, and the minimum load should not be less than 25% -30% of the unit's rated power to prevent diesel generators from malfunctioning during low load operation. This is not only beneficial for extending the service life of diesel generators, but also for better performance.

As a professional diesel generator manufacturer, we always insist on using first-class talents to build a first-class enterprise, create first-class products, create first-class services, and strive to build a first-class domestic enterprise. If you would like to get more information welcome to contact us via sales@dieselgeneratortech.com.