Reduced Voltage Motor Starting Panels by Reactors

 

Using a series reactor is one method that can help to lower the current when starting up a motor. Either iron or air core reactors can be used during startup. If an air core is used for the series reactor, then a very efficient and reliable soft starter can be designed, which is more suitable for high MW ratings of synchronous/induction motors at MV levels. All of our reactors are designed with taps.

 

Using a reactor during startup always reduces motor accelerating torque. Unlike with an autotransformer, voltage reduction in the reactor is not fixed, but rather varies with the current. Since this current is determined by total circuit impedance, motor voltage during acceleration depends upon the relative reactor and motor impedances.

 

General Options for RVMS Panels

  • Instead of an incoming vacuum contactor (IVC), a vacuum circuit breaker (CB) can be used
  • If a vacuum CB is used, no need to use MV fuses
  • Power factor correction capacitors
  • Incoming / outgoing surge arresters
  • Voltage transformers

 

Technical Specifications

  • Reactor types: Air core or iron core
  • Type of construction: Metal enclosed or metal clad
  • Rated voltage: Up to 15kV
  • Rated Current: Up to 1600A*
  • Ambient Temperature: -30°C to 55°C
  • Protection: Motor protection relay

* Consult factory for higher values.

 

 

Reduced Voltage Motor Starting Panels by Auto-Transformers

 

Reduced Voltage Motor Starting Panels(RVMS) are designed to be used in the startup of squirrel cage induction and synchronous motors.

 

An RVMS Panel reduces the torque by temporarily reducing voltage and/or current input. Voltage applied to the motor during start up is reduced, resulting in lower starting currents from the connected grid.

 

One way to limit the motor starting current is by placing an auto-transformer in series with the motor during startup. The transformer action reduces the voltage applied to the motor terminals, causing a decrease in current at startup.They are designed as per the standard voltage taps of 50%, 65% and 80%.

 

Technical Specifications

  • Autotransformer types: Dry type cast resin
  • Type of construction: Metal enclosed or metal clad
  • Rated voltage: Up to 15kV
  • Rated Current: Up to 1600A*
  • Ambient Temperature: -30°C to 55°C
  • Control: Digital controller based on motor current
  • Protection: Motor protection relay, Surge arrester for autotransformer

* Consult factory for higher values.

 

MV Soft Starter

 

This page is under construction.

 

Slip-Ring Motor Starting Panels

 

Slip-Ring Motor Starters are part of the series of resistors applied to rotor circuits in order to control the speed/torque characteristics of a motor.

 

Rotor starters are mainly used for motor startup applications requiring high-starting torque, such as loaded belt conveyors in the mining industry. By using external resistors, it is possible to shift the motor’s maximum (break-down) torque up to the starting torque point for motors under heavy loads during start-up. The resistors are split into steps and controlled via contactors by a motor startup control system. As the motor speed increases, the external rotor resistors are eliminated by shorting contactors until all external resistors have been shorted out.

 

Slip-ring motor starters are made in two types: dry- or oil-immersed.

 

Application

  • Fans
  • Pumps
  • Conveyors
  • Crane systems
  • Mill application
  • Mixer

 

Technical Specifications

  • Resistor types: Dry- or oil-immersed
  • Type of construction: Metal enclosed / metal clad
  • Rated voltage: Up to 15kV
  • Rated Current: Up to 1600A*
  • Ambient Temperature: -30°C to 55°C
  • Control: Digital controller based on motor current or time-relay
  • Protection: Motor protection relay

*For higher values, consult factory.

 

Braking Chopper for External Resistors

 

Braking chopper is used for limiting the DC link voltage of a frequency converter based motor drive. When an induction motor slows down, it acts as a generator and feeds energy back into the converter, and hence the dc link. The braking chopper transmits this braking energy of the drive to a resistor, to be dissipated as heat.

 

Typical applications of braking choppers are motor drives with high inertia loads such as trains, cranes, centrifuges, elevators, conveyors, large fans, etc.

 

Features

  • Suitable for all brands of 3Φ motor drives
  • Panel wall-mounted
  • Easy installation
  • Simple wiring
  • Simple operation
  • Maintenance free
  • High reliability
  • Smart digital control
  • Self and Remote RESET functions
  • Over-voltage protection (OV)
  • Over-temperature protection (OT)
  • Short-circuit protection (SC)
  • Resistor thermal protection (RT)
  • Led display for status and faults: “RUN”, “OV”, “OT”, “SC”, “RT”

 

Technical Specifications

  • Input Voltage: 650 VDC *
  • Suitable Drive Voltage: 400 VAC
  • Suitable Drive Power: 2.2 - 100 kW
  • Rated Continuous Current: 40A
  • Rated Pulsed Current (ED=10 %): 200 A
  • Rated Continuous Power: 26 kW
  • Rated Pulsed Power (ED=10 %): 130 kW
  • Minimum resistance value: 3.1 Ohm
  • Ambient Conditions: -10 to 40⁰C *, max 1000m * altitude
  • Storage Temperature: -25 to 70⁰C
  • Dimensions (WxHxD): 209,1mm x 293.4mm x 146,9mm
  • Weight : 4 kg
  • Protection Degree: IP 20, EN 60529
  • Parallel Operation: Up to 7 modules, approximately 1000kW peak braking power
     

 * Input voltage can be between 200-900VDC.

 ** For higher values, please consult us.