Soft starter
SH11/SH21

The most important advantages:
  • Simple cabling
  • Quick configuration
  • Universally applicable

Soft starter – SH21

SH11/SH21

Gentle protection for the engine and mechanics

The SH11/21 series ensures smooth starting (SH11) or soft starting and stopping (SH21) of asynchronous motors. Torque surges, current peaks, and voltage drops are a thing of the past, while the service life of your mechanical drive elements increases.

SH11 is suitable for single-phase and three-phase motors that require a progressive start-up.

The advantages

Soft starter SH11/SH21

A series of devices ranging from 0.37 to 55 kW. With 3 to 110 A rated current for asynchronous motors.
For voltage ranges: 110 to 480 V, 1~ and 3~ and power ranges: 0.37 to 55 kW.

Areas of application

Small compressors, fans
Conveyors, conveyor belts
Automatic doors
Car Washes

Product information

The SH21 series soft starters for progressive start-up and run-down are used to control the starting torque, reduce the starting current, and control the run-down in single-phase and three-phase motors.
The soft starters are designed for a voltage range of 110 to 480 V and are therefore universally applicable.

  • Operating status display with 2 LEDs
  • Booste entrance at SH21
  • Logic output for “run-up” signaling
  • No neutral conductor (Mp/N) required
  • Simple installation, even retrofitted
  • Jerk-free start-up and shut-down of all machines
  • Available for networks from 110 to 480 V
  • Suitable for all winding circuits
  • Suitable for V3 circuit
  • Top-hat rail mounting
  • Control voltage only required for SH11

In contrast to electromechanical starters, the electronic starters of the SH11/SH21 series allow the adjustment of the starting torque and the starting time.

The soft starters are particularly suitable for conveyors and conveyor belts, automatic doors, drag lifts, small gantry cranes, fans, pumps, refrigeration compressors, compressors and machines with high inertia and all machines with belt drive.

In the case of the SH11 series soft starters, the current in one phase, and in the case of SH21 in two phases, is controlled as a function of time by a rising voltage ramp.

The starting torque can be adjusted using a potentiometer.
A second potentiometer is used to adjust the ramp-up time according to the requirements.

With the SH21 devices, the deceleration time can be adjusted via a third potentiometer. SH21 devices also have a relay output that indicates the status of the soft starter.
After start-up, a built-in bypass relay bypasses the electronics and the motor runs directly on the mains.

Device overview

Type designationNominal
operating current
(A)
Motor
rated power
at 3 x 400 V
(kW)
Motor
rated power
at 1 x 230 V
(kW)
Motor
rated power
at 3 x 230 V
(kW)
Motor
rated power
at 3 x 460 V
(hp)
Dimensions
W x H x D
(mm)
Mass
(kg)
SH11-1.1/4231,10,371,522,5 x 100 x 100,40,16
SH11-3.0/4263,00,753,022,5 x 100 x 100,40,16
SH11-4.0/4294,01,15,045 x 124 x 130,70,28
SH11-5.5/42125,52,245 x 124 x 130,70,28
SH21-3.0/2260,751,145 x 124 x 130,70,42
SH21-4.0/2291,11,545 x 124 x 130,70,42
SH21-5.5/22122,23,045 x 124 x 130,70,42
SH21-11.0/22224,05,545 x 154 x 130,70,56
SH21-15.0/22325,57,545 x 154 x 130,70,56
SH21-3.0/463,045 x 124 x 130,70,42
SH21-4.0/494,045 x 124 x 130,70,42
SH21-5.5/4125,545 x 124 x 130,70,42
SH21-11.0/42211,045 x 154 x 130,70,56
SH21-15.0/43215,045 x 154 x 130,70,56
SH21-18.5/43818,511,025,055 x 165 x 1651,30
SH21-22.0/44522,011,030,055 x 165 x 1651,30
SH21-30.0/46530,018,540,055 x 165 x 1651,30
SH21-37.0/47337,022,050,055 x 165 x 1651,30
SH21-45.0/48045,022,060,081 x 222 x 1802,30
SH21-55.0/411055,030,075,081 x 222 x 1802,30
SH21-3.0/4664,045 x 124 x 130,70,42
SH21-4.0/4695,545 x 124 x 130,70,42
SH21-5.5/46127,545 x 154 x 130,70,42
SH21-11.0/462215,045 x 154 x 130,70,56
SH21-15.0/463220,045 x 154 x 130,70,56

Device types in bold: Preferred type, available from stock. Subject to prior sale.

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