Home Products News Contact Us
Home > Supports > Generators > The Principle of Automatic Switching Diesel Generator Sets

The Principle of Automatic Switching Diesel Generator Sets

Apr. 25, 2022

In order to quickly supply power to electrical equipment in some power supply systems, diesel generator sets are converted into intelligent automatic units, which can realize unattended, safe and free switching between power generation and mains. Such as hospitals, banks, real estate fire protection, and special enterprises where the power supply cannot be interrupted. Starlight Power Generation Equipment introduces the principle of automatic switching of diesel generator sets, so that everyone can better operate and maintain them in use.


standby genset


The main functions of the automatic switching diesel generator set system include automatic start, automatic speed increase, automatic power supply, automatic shutdown, low oil pressure alarm, high water temperature alarm, speed increase failure alarm and three start failure alarm functions. At the same time when a fault alarm is issued, the automatic engine closes the throttle of the diesel engine to realize automatic shutdown.


(1) Automatic starting and automatic switching of power supply: When the mains is interrupted, the mains switching circuit immediately cuts off the mains power supply circuit, and at the same time, the mains monitoring circuit makes the starter motor run through the self-starting controller, thereby starting the diesel generator set. After the start is successful, the oil pressure of the lubricating oil rises. When the oil pressure rises to the specified value, the oil pressure sensor is started successfully, and the control circuit of the electromagnetic field valve of the lubricating oil circuit is connected. The pressure lubricating oil pushes the cylinder piston and drives the throttle handle to move in the direction of speed-up. Under the action of the speed-up limit controller, the diesel engine works at the rated speed. At this time, under the action of the automatic voltage regulator, the generator outputs the rated voltage. Then, the power generation switching circuit is turned on, and the diesel generator set starts to supply power to the load.

(2) Automatic shutdown after the mains is restored: After the mains is restored, under the action of the mains monitoring circuit, the diesel engine power supply circuit is first cut off, then the mains switching circuit is put into operation, and the load is powered by the mains. At the same time, the self-starting controller makes the stop electromagnet act to control the throttle of the diesel engine. The diesel generator set runs at low speed first, and then automatically stops.

(3) Fault shutdown and alarm: During the operation of the unit, when the outlet temperature of the cooling water reaches 95℃±2, the temperature controller sends out an audible and visual alarm signal through the system controller and cuts off the load. At the same time, the shutdown electromagnet acts, and the diesel The generator set stops running.

(4) During the operation of the automatic switching diesel generator set, when the oil pressure of the lubricating oil is lower than the specified value, the contact of the low oil pressure alarm sensor is closed, the controller sends out an audible and visual alarm signal through the display alarm device, and at the same time cuts off the oil motor Switch the circuit, then stop the electromagnet to run, and the diesel generator set will automatically stop. When the speed of the unit exceeds the rated speed, the high-cycle relay in the diesel-electric monitoring circuit will act, and the diesel generator set will automatically stop.


Starlight Power was founded in 1974 and is one of the earliest manufacturers of generators and diesel generator sets in China. If you want get more information, please feel free to send email to sales@dieselgeneratortech.com we will pay highly attention on your question.

Contact Us
  • Add.: Room 601, Laboratory Building, No.2 Gaohua Road, Nanning, Guangxi, China.
  • Tel.: +86 771 5805 269
  • Fax: +86 771 5805 259
  • Cellphone: +86 134 8102 4441
                    +86 138 7819 8542
  • E-mail: sales@dieselgeneratortech.com
Follow Us

Copyright © Guangxi Dingbo Power Equipment Manufacturing Co., Ltd. All Rights Reserved | Sitemap

Contact Us