Soft Starter

60–2,500 A and 1,500–15,000 V

ITS-HD Digital Medium Voltage Transformer Starter

Advantages at a glance

  • Up to 50°C ambient temperature
  • Comprehensive motor protection and control package
  • IP 41 as standard, up to IP 65 optional
  • Advanced electronic potential transformer utilizing patent pending “wireless” voltage measurement system
  • Wide 50 – 60Hz range
  • Engineering included
  • Closed control circuit by current measurement, Back-up via time control
  • Innovative low voltage test – testing of complete function
  • Nominal voltage test – option
  • Optic data logging
  • Real-Time-Clock


For full view please move the table horizontally if necessary.
System Voltage Current Motor Dimensions Weight
kV A kW W (mm) H (mm) D (mm) kg
2.3 60–2,500 170–5,400 900–1,100 2,300 900–1,200 500–1,200
3.3 60–2,500 250–7,700 900–1,100 2,300 900–1,200 550–1,250
4.16 60–2,500 320–9,200 900–1,100 2,300 900–1,200 550–1,300
6.0 60–2,500 540–14,000 1,100–1,500 2,300 900–1,300 850–1,350
6.6 60–2,500 600–15,500 1,100–1,500 2,300 900–1,300 850–1,350
10.0 60–2,500 910–23,000 1,400–3,500 2,300 900–1,400 2,100–2,800
11.0 60–2,500 1,000–25,500 1,400–3,500 2,300 900–1,400 2,100–2,800
13.8 60–2,500 1,260–31,500 1,600–4,200 2,300 900–1,400 2,800–3,100
15.0 60–2,500 1,370–35,000 1,600–4,200 2,300 900–1,400 3,150–4,200


1) Case by case

Current limit

The voltage increases linearly from the “Initial Voltage“ pre selected point. If the adjusted “Current Limit” is reached, the voltage will stop ramping and remain at its level until the current is reduced below the adjusted “Current Limit“ level. In that case ramp up time is prolonged until the current has reduced below “Current Limit” level 

Soft starter output voltage

Although the current is limited the motor provides suitable torque to accelerate the driven load and reach “End of acceleration”. If the motor torque does not exceed the load torque the motor will not start. In the so rare cases severe damages might occur to the motor and starter.

Motor start measured with an oscilloscope
(Ch1, voltage; Ch2-4 current L1 – L3)

The oscillogram shows, the soft starter providing a smooth and stepless current and voltage ramp to the motor. The voltage ramps up until “Current Limit” is reached. After the motor is at nominal speed, the current will decrease, to the nominal motor current.


  • Illuminated LCD with 2 lines of 16 characters each
  • Selectable languages: English, German, French or Spanish (aditional on request)
  • The LCD indicates the motor current, fault descriptions and statistical data.
  • The LEDs provide a quick status indication. (control voltage on, motor soft start, motor on, motor soft stop, motor stop, fault)
  • Easy settings by six clearly marked keys, user-friendly software with factory default parameters.

Communication RS 485

Modbus Profibus

RS 485 with MODBUS or PROFIBUS protocol enable:

  • Remote (start, stop, etc.)
  • Monitoring (motor current, faults, statistical data)
  • Remote parameter setting
  • Remote reset


Internal bypass

  • This reliable components bypass the power electronics after the motor is at speed.
  • In addition the starters provide an auxiliary contact, allowing signaling of a successful motor start.
    Attention! Many of our competitors call these auxiliary relays “a bypass contact”!
  • The bypass function reduces the heat dissipation and eliminates the EMC load of the system.