Soft Starter

200 kW – 30,000 kW

ISA-TS – IGBT based Medium Voltage advanced Soft Starter – The first of its kind

Designed for applications that require low starting current and high starting torque.

Advantages at a glance

  • High starting torque from standstill (up to 80 % of the motor’s pull-out torque)
  • Capable of long starting time without forced cooling
  • Freely adjustable acceleration characteristics, no speed encoder required
  • Provides a solution for applications which do not require motor speed and/or torque control during operation, but where soft starting with reduced voltage is not suitable
  • Starts most of the driven machines with nominal current or less
  • Automatic synchronization with the mains
  • No increased current or torque shock during synchronous transfer
  • Integrated bypass function
  • No start-related heat losses in the rotor
  • Low line harmonics
  • No torque surge at energizing
  • No torque pulsations on the drive train
  • No significant dV/dt stress on the motor windings

Why did we developed another type of starter?

  • The available starting torque is significantly higher compared to conventional methods with reduced voltage.
  • Some grids cannot tolerate even e.g. “only” three times nominal motor current – ISA-TS can be set to a starting current even below nominal.
  • The run-up characteristic is freely adjustable regarding run-up time and acceleration ramp.
  • The motor is operated at its nominal slip frequency during the whole starting process.
  • The motor can be started any number of times without suffering from thermal stress.
  • In case of a power supply interruption the motor can be “caught” at any speed, re-accelerated to line frequency and synchronized again.

Your cost savings

  • Significantly lower price compared to a medium voltage VFD of similar starting and stopping performance.
  • Integrated bypass avoids losses during continuous operation direct on line, thus saving operational costs.
  • Reduction of peak power demand from the grid
  • Optionally integrated incoming disconnector switch with no increase in cabinet size
  • No need for a cooling system, only natural convection – no maintenance, no noise, no moving parts
  • Streamlined design translates into at least 50 % reduction in footprint compared to a VFD with equivalent performance

Technical specifications

  • Input voltage up to 11 kV 50/60 Hz + 10 %/ –15 %.
  • For motors in the power range from 200 kW to 3000 kW Mains starting current adjustable from 10 % to 120 % of motor rated current
  • Starting capacity of 100 % of FLC for 600 seconds at 50 °C ambient, numerous number of starts
  • Starting torque up to 180 % of motor rated toque
  • Internal synchronization system (bypass), from TorqueStart to mains and back
  • Soft start and soft stop
  • Multi-start capability
  • Electronic potential and current transformer (EPCT) for voltage and current measurements via fiber optics
  • Integrated data logger and wave form capture for all relevant system signals (current and voltage)
  • Option for remote diagnostics and failure analysis

Industries and Applications

Water/waste water pumps
Booster Pumps
Desalination plants

Oil and gas
Screw type pumps
Recip pumps
Gear pumps
Diaphragm pumps

All types of compressors
Refrigerating compressors – even against full system pressure
Mixers and extruders
Sinter fans
Descaler pumps
Compressors for air separation plants
Blast furnace blowers

Fans and blowers
Conveyor belts
Ball mills and vertical mills

Thruster drives
Cargo pumps
Positioning drives for floating platforms