• Line protection link

    Line protection link

    1. Short-circuit protection When a short circuit occurs, the main circuit is cut off by the fuse of the fuse FU. In order to expand the protection range, the fuse is as close to the power supply as possible in the line, and is generally installed directly under the knife switch.   2. Overload prote... read more

    18-11-2020 News
  • Design principles of PLC control system

    Design principles of PLC control system

    The essential difference between a programmable controller and a traditional relay control system is the use of the scanning mode and the concept of a relay. PLC system design includes two parts: hardware design and software design. The design method of parallel development of hardware and software... read more

    18-11-2020 News
  • The role of the contactor

    The role of the contactor

    The contactor is an automatic electromagnetic type electric appliance, which is suitable for frequently connecting and disconnecting AC and DC main circuits and large-capacity control circuits over long distances. It is mainly used in automatic control of AC and DC motors, electric heating equipmen... read more

    18-11-2020 News
  • Speed control circuit of multi-speed machine

    Speed control circuit of multi-speed machine

    The synchronous speed of the motor n = 60 f / P. When the grid frequency f is fixed, n is inversely proportional to the number of pole pairs P. If the number of pole pairs P can be changed, then n will also change. Pole-changing speed regulation is only applicable to cage asynchronous motors. Multi... read more

    18-11-2020 News
  • Introduction to contact systems

    Introduction to contact systems

    The contact system is the actuator of an electrical appliance, and it functions to open and close the circuit. Therefore, the quality of the contacts directly affects the working performance of the entire appliance. There are many types of contact mechanisms, and according to their contact types, t... read more

    18-11-2020 News
  • Basic Technology of Power System Dispatching Automation

    Basic Technology of Power System Dispatching Automation

    Power system dispatching automation collects real-time information on the operation of the power system through the remote terminal (RTU) installed in each power plant and substation, and transmits it to the dispatching master station (MS) via the communication channel. Perform safety analysis, loa... read more

    18-11-2020 News
  • About the outline classification of the relay

    About the outline classification of the relay

    According to the size of the relay: 1) Miniature relays: relays with the longest side dimension not greater than 10 mm. 2) Ultra-compact miniature relays: relays with the longest side dimension greater than 10 mm, but not greater than 25 mm. 3) Miniature relays: relays with the longest side dimensi... read more

    18-11-2020 News
  • Introduction of low voltage circuit breaker

    Introduction of low voltage circuit breaker

    Low-voltage circuit breakers are also called automatic air circuit breakers, or automatic switches for short. Low-voltage circuit breakers are functionally equivalent to a combination of knife switches, fuses, thermal relays, and undervoltage relays. Their function is not only to frequently turn on ... read more

    18-11-2020 News
  • Principles for determining the control plan

    Principles for determining the control plan

    There are many electrical control methods for equipment, including relay contactor control, non-contact logic control, programmable controller control, computer control, etc. In short, the reasonable determination of the control plan is an important prerequisite for the realization of a simple, reli... read more

    18-11-2020 News