Reasons for Difficult to Start Diesel Generator Sets at Low Temperature

Diesel generator sets are difficult to start at low temperature because the temperature and pressure in the cylinder are too low at the end of the compression stroke due to the low air temperature, fast heat dissipation, and low crankshaft speed, which cannot reach the spontaneous ignition temperature of the fuel. In general, diesel engines require that the temperature in the cylinder after compression reach more than 400 °C and cannot be lower than 350 °C. Below, Starlight power generation equipment will analyze the reasons and effective measures for you.

Diesel generator sets are difficult to start at low temperatures in winter. The reasons are analyzed by the diesel generator set manufacturers as follows:

(1) Due to the low gas temperature, fast heat dissipation, and low crankshaft speed, the temperature and pressure in the cylinder at the end of the compression stroke are too low to reach the spontaneous ignition temperature of the fuel. In general, diesel engines require that the temperature in the cylinder after compression reach more than 400 °C and cannot be lower than 350 °C.

(2) The viscosity of lubricating oil increases greatly at low temperature, or even solidifies, which increases the starting resistance of the engine and cannot reach the low speed required to start the engine (generally above 100r/min (revolution/min)).

(3) At low temperature, the terminal voltage of the battery is reduced, the capacity is reduced and the charging is insufficient, so that the starting motor cannot reach the starting speed when driving the crankshaft, or even cannot be driven at all.

In view of the above reasons for the difficulty in starting, the following measures can be taken when the diesel generator set is started:

(1) The starting fuel with light fraction, high evaporation and low self-ignition point is used to solve the problem that diesel oil is not easy to spontaneously ignite at low temperature.

(2) Use thickened oil instead of ordinary oil to solve the difficulty of crankshaft rotation at low temperature.

(3) The main component of the starting fuel for diesel generator sets is ether, and there are various formulas. The effective and simple formula is: 70% ether + 27% aviation kerosene + 3% No. 10 gas engine oil. The auto-ignition point of the mixture is only 191°C, so it is easy to ignite in a diesel engine. Practice has proved that the use of starting fuel and thickened oil can ensure that the diesel generator set can start quickly when the temperature is -45℃.

Starlight Power has advanced testing equipment, modern production technology, professional manufacturing technology, perfect quality management system, and strong technical research and development capabilities. It can provide 3KW～2500KW various specifications of ordinary, automatic, four protection, automatic switching, low noise and mobile generator sets, high quality and low energy consumption to meet the diverse power needs of customers, and can also meet users with different voltages and different frequencies. It is required to create a parallel power supply system for multiple units. If you are interested in our product or any question on generator, welcome to send email to sales@dieselgeneratortech.com.