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RQ-4 soft starter

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Product description


  RQ-4 motor soft starter is a new motor starting and protection device that combines power electronic technology, microprocessor and automatic control. It can start / stop the motor smoothly without steps, avoiding mechanical and electrical shock problems caused by starting the motor using traditional starting methods such as direct starting, star / delta starting, and auto-buck starting, and can effectively reduce starting. Current and power distribution capacity to avoid increasing investment. At the same time, the current transformer is integrated inside the RQ-4 soft starter, and the user does not need to connect it externally.


  ◆ Unique SCR trigger closed-loop control algorithm

  Unique SCR closed-loop control function, specially designed for standard load and heavy load. The user can choose current limiting start and voltage ramp starting according to the load conditions to achieve an absolutely smooth torque-free vibration starting effect.

  ◆ High control accuracy, real-time efficiency

  Adopt high-performance Cortex-M3 32-bit core CPU to perform central control, with fast speed, high precision and strong anti-interference ability.

  ◆ Beautiful appearance

  The patented main circuit has a three-in and six-out structure and a built-in current transformer scheme, which is convenient for wiring and high in reliability.

  ◆ Configurable standard MODBUS-RTU protocol

  When ordering, users can choose standard MODBUS-RTU communication protocol with or without according to the needs of the site.

  ◆ Integrated advanced protection functions

  With input and output phase loss, overload, overcurrent, phase current imbalance, thyristor overtemperature and other protection functions, it can protect the motor and related equipment in all directions.

  ◆ Full refractory

  Below 90KW is a full plastic shell structure, which is made of flame-retardant ABS material. The upper cover of the power section of 90KW and above is a plastic shell structure, and the main frame is made of aluminum-coated zinc plate material.

  ◆ External panel

  The panel can be led to the operation surface of the equipment for remote operation through the interface of the fuselage, which is convenient for on-site use.

  ◆ Simple maintenance

  The monitoring signal coding system composed of 4 digital displays can monitor the working condition of the system equipment 24 hours, and provide fast fault diagnosis.


  Soft starter model description


  Basic wiring diagram


  Soft starter terminals 1L1, 3L2, and 5L3 are connected to a three-phase power supply, and 2T1, 4T2, and 6T3 are connected to a motor. The soft starter can choose whether to detect the phase sequence through parameter setting. When the bypass contactor is used, the contactor is connected to the soft starters 1L1, 3L2, 5L3 on one side, and B1, B2, B3 on the other side.

  Note: The communication interface is a functional optional port, which uses fiber optic crystal head connection terminals, as shown in the figure from the top to the bottom from 1 to 8 feet. Please refer to the terminal definition for the specific terminal definition.


  Terminal description

  RQ-4 series soft starters have 12 external control terminals, which provide convenience for users to realize external signal control, remote control and system control.


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Address: Building 3, Xingsha International Enterprise Center, Changsha Economic and Technological Development Zone

Changsha Hengkai Electrical Equipment Co., Ltd.