GKGR 3-in-1 HV vacuum soft starter cabinet for mining (hereinafter referred to as soft starter cabinet) is signaled as “kA”, applies to coal mining places of no hazards, gas, dusts, explosives and non-coal mines places of an underground control room, an underground parking lot, main ventilation duct, mechanical and electronic chamber. It also can be widely used in aboveground places of large steel plant, petrochemical plant, sewage treatment plant, power plant and so on.
A complete soft starter cabinet includes power module, silicon controlled rectifier (SCR) module, motor protection module, communication module and so on. The control core of a soft starter cabinet is a microprocessor (CPU), which starts and protects the motor.
CPU controls the SCR to conduct phase angle trigger control, lowering the voltage on motor, then controls the voltage on motor and increases the motor torque of the smooth current until motor runs in full speed. The above way of starting can lower the inrush current of motor, reducing the impact on power grid and motor itself. Meanwhile, it also reduces the mechanical impacts on motor loading device, prolonging device service life and reducing motor breakdown.

Product Features:

Structure Features

It adopts the isolation setting of three rooms, namely the power component room, main control relay room, main circuit connection room.

Electrical Features

A qualified controlling system passed through the strict test of Electro Magnetic Compatibility, processes with a high anti-electromagnetic interference performance; has fully independent intellectual properties in soft starter controlling technology; is capable of providing free service for users in upgrading software control systems to ensure an advance place of its products and technology.
Negative feedback function: it adopts the dynamic fuzzy control concept to automatically adjust motor’s starting time and torque according to the size of load torques, realizing smooth acceleration in motor. When motor speed reaches the rated working level, the bypass contactor shall automatically pull in, which solves an unmatched problem between man-made starting curve and load torque curve. Also known as a unique feature in MV/HV solid soft starter cabinet of our company compared to domestic peers.

Strong load adaptability, and GKGR has 3 ways of starting and controlling mode:

Voltage ramp start: a voltage ramp with current limiting function according to factory defaults shall be used in most occasions. The original value of torque shall be set to the one happens to drive the load before a smooth increase in voltage. The motor gets a smooth rise to full-speed operation in limited ramp time and starting current.

Current-limiting start: In starting, the current shall accelerate to a limited value, until the motor runs in full voltage;

Direct start-up；

An option between free parking and soft parking: it can be used in many parking occasions, for example, erase a water hammer effect of the pump to meet special needs;

Text display function: a wide choice of all kinds of working conditions and languages displayed in LED screen, both programming and faults shall be explanatory noted for easy operation.

System communication function: it has inbuilt communication ports. It enables the RS-485 and multipoint communication (an option between the communication protocol Modbus and Profibus) in remote terminals communicate directly with the upper PC machine to realize telecontrol, remote message and other functions.

Trigger circuit- provides strong trigger pulses up to 2A to ensure the dynamic voltage equalizing of SCR in series. The trigger circuit and SCR are with high voltage, isolated from the control panel through optical fiber and transformer.

SCR high voltage components - are composed of multiple SCR in series, the number of which shall be determined by the user's motor voltage.

2.High voltage current transformer and vacuum circuit breaker coordinate in providing motor protection.
3.The high voltage part communicates with the low voltage control part through optical fiber.
4.The inbuilt 220VAC control transformer provides the control power needed for the soft starter.
5.Bypass vacuum contactor
6.   Isolation transformer
7.Control panel
8.   Zero-sequence current protection (Optional)
9. Silicon controlled rectifier (SCR) 630066
10.   Over-voltage Absorber

Technical Indexes ：

1. Ambient air temperature: no more than +50℃, and the average temperature in 24 hours shall be no higher than +45℃ and no lower than -20℃.
2.  With clean air and a relative humidity of no more than 50% in the highest temperature of +50℃, and a relative higher humidity in lower temperature, for example, 90% of humidity in an no condensation environment of +20℃.
3. An altitude of no more than 2000m, otherwise an extra agreement shall be made.
4.It shall be used in places of no fire, explosion, heavy dust, chemical corrosion or violent shocks;
5. The soft starter cabinet shall be delivered and stored in the following temperature: -25℃~+55℃, no more than +70℃in less than 24 hours. (If the above conditions of use failed to be satisfied, the user shall consult with the manufacturer on technical problems.)

Statement on Product Model:

Applications

It is widely used in squirrel cage ac asynchronous or synchronous motors of coal mines, non-coal mines, electric system, machinery manufacturing, cement production, metallurgy, oil extraction, chemical industry, water treatment and other industries. It shall be used for motor start-up, control, protection and soft stop as a three phase voltage of 3KV to 10KV.

Model Selection Table of GKGR HV Vacuum Soft Starter Cabinet for Ordinary Mining Type

Remark ：

1. When the rated current of a motor is larger than +8% of current limit, we shall choose the product with a higher power.
2.  When the motor power is higher than the motor power, we shall choose the product with a higher power.
3.  If the motor power is above 2000kw, a differential protection box shall be added;
4. The rated current of the soft starter shall be stated according to the rated current of user’s motor.

Schematic Diagram of HV Vacuum Soft Starter Cabinet for Ordinary Mining Type

Installation Figure of a Soft Starter Cabinet

Primary Circuit Diagram of Soft Starter Cabinet