Maintenance Cycle Time and Test Contents of Diesel Generators

The importance of diesel generator sets in factories and enterprises is unquestionable. In order to ensure the normal standby and stable operation of diesel generator sets, their regular testing and daily maintenance are particularly important. Taking Cummins diesel generator sets as an example, this article explains the items that need to be checked during the regular test of diesel generator sets, as well as the safety matters that need to be paid attention to in the daily maintenance and overhaul of diesel generator sets

Maintenance cycle time of diesel generators

The maintenance cycle of diesel generators is usually determined by the frequency of use and the use environment. If the diesel generator is in a high-load operation state for a long time, the maintenance cycle should be more frequent than that in normal use. If the diesel generator encounters some special environments during use, such as extremely high altitude areas, etc., then the maintenance cycle needs to be appropriately extended according to the situation. Generally speaking, it is recommended to maintain every 500 hours or at least once a year to ensure the operating efficiency and safety of the diesel generator. If an abnormality is found in the use of the diesel generator, it is also necessary to notify professional maintenance personnel in time for inspection and repair.

Periodic start test of diesel engine

1. Inspection items before periodic start test

• Air filter: The air filter element should be installed and clean to prevent unfiltered air from entering the engine.
• Air intake: The air intake should be clean and not blocked.
• Battery: The battery connection should be tight and the battery voltage should be above 24V.
• Coolant level: The coolant level should be kept between the high and low scale lines. The coolant temperature should not be lower than 37℃. If the energized heating element is not immersed in coolant, the cylinder heater will be damaged. Before turning on the cylinder heater, fill the cooling system, run the engine until it becomes hot, and then add coolant to the radiator to remove air from the cooling system before the cylinder heater is powered on.
• Drive belt: Check the belt condition and the tension of the cooling fan, water pump and battery charging generator belt.
• Exhaust system: The exhaust system must not leak or be blocked. Check the condition of the muffler and exhaust pipe, and check the tightness of the exhaust system connections. Check the exhaust system components (exhaust manifold, exhaust electrical connections, exhaust hoses, clamps, muffler and exhaust pipe) for cracks, leaks and corrosion. Metal parts must not be corroded or broken, otherwise they need to be replaced. Clips and hooks should not be loose, corroded or detached. Tighten and/or replace exhaust pipe clamps and hooks as necessary. The exhaust port should not be blocked. Visually inspect the exhaust system for leaks (air leaks). Check for carbon deposits or carbon black residue on exhaust components. Carbon and carbon black residue indicate exhaust leaks. Seal as needed.
• Fuel level: Check the fuel level and keep the fuel tank full to ensure adequate fuel supply.
• Engine oil level: The engine oil level should be kept at the full mark on the dipstick, or close to it, but not exceeding it.
• Work area: Check the site for obstacles that affect the flow of cooling air. Keep the air intake area clean. Do not leave rags, tools or debris on or near the generator set.

2. Inspection items after regular start-up test

After the pre-startup inspection is completed, the duty officer starts the diesel generator set through the remote computer. After starting, the diesel generator outlet switch automatically closes, and the switch closing indicator lights of each phase are on. Check that there are no abnormalities in the sound and vibration of the diesel generator. After running for 15 minutes, check the following items and make records

• Coolant temperature: The coolant temperature must not exceed 92℃℃.
• Battery voltage: The battery voltage is below 32V.
• Machine end voltage: Check that the machine end line voltage of the diesel generator is 400V+10%.
• Generator speed: Check that the diesel speed is 1500r/min+2%.
• Fuel pressure: Check that the fuel pressure is greater than 393kPa.