Technical Specifications of Current Transformers in Diesel Generator Control Panels

The main function of a diesel generator set control panel is to distribute the electrical energy output by the generator to user loads or electrical equipment. It also indicates the operating status of the diesel generator and maintains the generator's voltage stability under varying load conditions. A simple diesel generator set control panel typically contains components such as a voltage regulator, silicon rectifier diodes, rheostats, automatic air switches, and current transformers. More complex control panels may additionally include overload and short-circuit protection devices, electronic speed governors, thyristors, relays, various safety devices, and small transformers.

A current transformer is an instrument that converts a large primary-side current into a small secondary-side current based on the principle of electromagnetic induction. It consists of a closed iron core and windings. The primary-side winding has very few turns and is connected in series with the circuit whose current needs to be measured.

1.Generally, current transformers with an accuracy class of 0.5 should be used for electricity meters intended for billing purposes, while class 3 current transformers can be used for measuring instruments in non-critical circuits.

2.The accuracy of a current transformer is related to its operating capacity. Therefore, its operating capacity must be less than or equal to its rated capacity. Specifically, the secondary-side operating current of the current transformer should be less than or equal to the rated secondary-side current, and the secondary-side load (taking the maximum phase among the three phases) should be less than or equal to the rated secondary-side load. If the calculated primary-side load exceeds the secondary-side load, two current transformers of the same model and transformation ratio can be connected in series in the forward direction, which doubles the secondary-side load capacity. Key technical parameters of commonly used current transformers in generator sets, such as models LQC-0.5 and LM-0.5, are provided in the table below.

3.The wiring polarity of the current transformer must be correct; otherwise, the readings of measuring instruments will be inaccurate, and corresponding relay protections may malfunction.

4.The current coils of the secondary-side load of a current transformer should be connected in series, not in parallel. Only through series connection will the current flowing through each coil be equal, ensuring an accurate reflection of the current in the circuit.

Guangxi Dingbo Power Equipment Manufacturing Co.,Ltd was founded in 1974 and is one of the earliest manufacturers of generators and diesel generator sets in China. The company has a registered capital of 218.88 million yuan. The company covers an area of 86,000 square meters and a building area of 55,000 square meters. There are more than 660 employees, including 456 professional technicians and 106 senior technicians. It has 46 sales and service outlets nationwide. The main products are diesel engines, generator sets, and diesel generators, providing users with a one-stop service of design, supply, debugging and maintenance at any time. Dingbo has always insisted on using first-class talents, building first-class enterprises, manufacturing first-class products, creating first-class services, and making every effort to build a first-class domestic enterprise. If any question please feel free to visit our website https://www.dieselgeneratortech.com/ or send email to [email protected].