Soft start and soft stop

Soft start and soft stop overview

Soft start and soft stop overview

A soft starter is an electronic motor control device for the soft start and stop of three-phase induction motors. The motor voltage is adjusted with a phase control by a ramp function. The supply frequency of the motor remains identical to the mains frequency. With soft starting, the initial voltage (= starting torque) and the voltage rise (= acceleration) are adjustable. During soft stop, the voltage is reduced with a ramp function.

Applications:
* Speed control e.g. of fans and blowers 
* Motor starting – conservation of resources

Sanftanlaufgerät SoftCompact

SoftCompact® AM, SM

Start attentuation (AM) and soft starters (SM, SM2)
0,5 – 7,5 kW

Features Application
  • 1- or 2-phase controlled
  • AM Start attenuation with bridging relay
    SM Soft start with bridging relay for single-phase capacitor motors
    SM2 Soft start with bridging relay and soft stop
  • Switch-on torque and run-up voltage ramp separately adjustable
  • Module housing for mounting on 35 mm DIN rails. Very compact version with a width of 45 mm.
  • With integrated bridging contactor
  • Easily retrofitted
  • Can be used as a combined soft-start and injection brake using the electronic brake modules LEKTROMIK B1
  • Conveyor belts
  • Packing equipment
  • Long-travel drives for cranes
  • Compressors
  • Heat pumps
  • Vibration transporters
  • Machines with gearbox, belt or chain drives
  • Special version for pole-change motors
LEKTROMIK<sup>®</sup> S2, SD2

LEKTROMIK® S2, SD2

Soft start and soft stop LEKTROMIK®S2, SD2
4 – 2000 kW

Features Applications
  • 3-phase control
  • Wide voltage range 3AC 110 – 500 V or 3AC 220 – 690 V
  • Ramp-up time, ramp-down time and starting torque adjustable
  • Ramp-up times up to 100 s possible
  • Can be combined with electronic DC injection brakes
  • Current limit and upgrading with special functions
  • Control of external bridging contactor
  • Can be used as voltage controller
  • S2: Option I2 integrated
  • SD2: “Delta” connection (6 motor cables)
  • Pumps
  • Fans and compressors
  • Refrigeration compressors
  • Conveyor belts
  • Grinding machines
  • Saws
  • High speed and high load belts
  • Drives with pole-change motors
  • Machines with gearbox, belt or chain drives
  • Centrifuges