The Schneider SSP05EMA12 is an Altistart 22 series soft starter designed for three-phase asynchronous motors. Rated at 5A with a supply voltage of 200-240V AC, this soft starter provides smooth acceleration and deceleration of motors up to 1.1kW (1.5 HP). It reduces mechanical stress on driven machinery and eliminates electrical disturbances caused by direct-on-line starting. The unit integrates a bypass relay that automatically engages after starting to reduce heat dissipation, allowing it to be mounted in small enclosures without external ventilation. The Altistart 22 series is known for its compact size, ease of configuration, and built-in motor protection functions including thermal overload, phase loss, and jam detection.
Rated operational current (Ie): 5 A (for standard duty). Motor power: 1.1 kW at 200-240V AC. Supply voltage: 200-240V AC, 50/60 Hz. Control voltage: 24V DC (integrated). Starting torque: adjustable from 0 to 100% of motor rated torque. Deceleration torque: adjustable for soft stopping. Protection functions: thermal overload (class 10, 20, or 30 selectable), phase loss, phase imbalance, motor jam, and short-circuit. Built-in bypass relay: operates after start to reduce losses. I/O: 2 logic inputs (start, stop), 1 analog input (0-10V or 4-20mA for torque reference), and 2 relay outputs (fault, run). Communication: integrated Modbus RTU (RS-485) as standard. Dimensions: 55 mm (W) × 144 mm (H) × 131 mm (D). Weight: 0.8 kg. Protection rating: IP20. Operating temperature: -10°C to +40°C. Storage: -25°C to +70°C. Standards: IEC 60947-4-2, UL, CSA, CE.
5A rated current for 1.1kW motors at 230V
Soft start and soft stop with adjustable torque
Built-in bypass relay for energy efficiency and reduced heat
Integrated motor protection (thermal, phase loss, jam)
Modbus RTU communication for remote monitoring and control
Compact 55mm width for space-saving installation
DIN rail or screw mounting
Easy configuration via integrated potentiometers
LED status indicators: power, run, fault
The SSP05EMA12 uses thyristor (SCR) voltage control to gradually increase the voltage applied to the motor during starting, thereby limiting inrush current and torque. After the start ramp is completed, the built-in bypass relay closes, shorting the SCRs and eliminating power dissipation. For stopping, the relay opens and the SCRs progressively reduce voltage, providing a smooth stop. The starting torque is adjustable via a potentiometer on the front panel, as are the start ramp time and stop ramp time. The device also offers a kickstart function for high-friction loads.
The soft starter includes an electronic thermal overload relay with selectable trip classes (10, 20, or 30). It also detects phase loss (open circuit) and phase imbalance (voltage or current difference). A jam protection function trips if the motor current exceeds a settable threshold for a defined time. Short-circuit protection is provided by an internal fuse (replaceable) or external fuses. All protection functions are configurable via DIP switches and potentiometers. The unit also includes a PTC thermistor input for direct motor winding temperature monitoring (optional).

The SSP05EMA12 is suitable for motors driving fans, pumps, conveyors, compressors, and small centrifuges where reduced starting current and smooth torque are beneficial. Typical industries include HVAC, packaging, material handling, and general machinery. The built-in Modbus RTU allows integration into PLC-based systems for remote start/stop and monitoring of current, thermal state, and fault status.
Mount the soft starter on a DIN rail or with screws to a panel. Provide clearance of at least 50 mm above and below for ventilation. Connect the three-phase supply to L1, L2, L3 terminals and the motor to T1, T2, T3. Connect the control voltage (if using internal 24V, no external supply needed). For external start/stop, connect a maintained or momentary switch to the logic inputs. The analog input can be connected to a PLC output or potentiometer for torque control. Modbus wiring uses two-wire RS-485 (A, B). Use appropriate fuses (e.g., 10A gG) upstream for short-circuit protection.
Configuration is performed via DIP switches and potentiometers on the front panel. Settings include: start ramp time (1-10s), stop ramp time (0-10s), initial torque (0-80%), motor full load current (1-5A), trip class (10,20,30), and kickstart enable. The device also has an auto-tuning mode that measures motor parameters during first start. A potentiometer labeled "SMO" adjusts the deceleration shape for soft stopping. For advanced configuration, the Modbus communication can be used.
The soft starter is maintenance-free. The front LEDs indicate: green "POWER" for input voltage, yellow "RUN" when motor is powered, red "FAULT" for overload, phase loss, or jam. The fault can be reset manually by cycling power or via a remote reset input. The device stores the last fault code. Periodic checks of terminal tightness and ventilation are recommended.
The SSP05EMA12 is CE, UL, and CSA certified. It meets IEC 60947-4-2 and RoHS. Operating temperature: -10°C to +40°C (derate above 40°C). Humidity: 5-95% non-condensing. Vibration: 2g (10-55 Hz). IP20 protection requires installation in a control cabinet.
The Schneider SSP05EMA12 Altistart 22 soft starter provides efficient motor starting with built-in bypass and comprehensive protection. Its compact size, easy configuration, and Modbus connectivity make it a practical solution for controlling small three-phase motors in industrial automation.



