SND ATS48D38Q Soft Starter (Torque Control)

The SND ATS48D38Q is a microprocessor-controlled soft starter designed to reduce mechanical stress and electrical inrush currents in three-phase induction motors. It uses patented torque control technology to provide smooth acceleration and deceleration, extending the life of motors and driven equipment.

Main Specifications

• Rated current (standard): 38 A (10-minute overload 46 A)

• Motor power (230V): 11 kW; (400V): 22 kW; (460V): 30 HP

• Supply voltage: 208–690 V AC, 50/60 Hz

• Control supply: 110–230 V AC internal

• Number of start cycles: Up to 6 per hour (heavy duty), 20 per hour (light duty)

• Integrated bypass: Yes (thyristor bypass)

Torque Control System (TCS)

Unlike conventional voltage ramp soft starters, the ATS48D38Q controls motor torque directly, compensating for load variations. This results in linear acceleration regardless of load inertia, preventing belt slip or gear shock. The deceleration control avoids water hammer in pumping systems.

Protection Functions

The unit includes motor thermal protection (I²t), phase loss, phase unbalance, overcurrent, short-circuit on SCR, and stall protection. It also monitors heatsink temperature and provides alarms via a configurable relay output. All protection thresholds are adjustable via the keypad.

User Interface and Setup

A backlit graphic display shows motor current, thermal state, and diagnostic messages. Setup is guided by a simple menu with parameters grouped logically. Advanced settings include kickstart for high-friction loads, dual ramp for two-speed applications, and pump cleaning function.

Communication and Integration

The ATS48D38Q comes with MODBUS serial communication as standard. Optional fieldbus modules (PROFIBUS DP, DeviceNet, Ethernet/IP) are available. It also features three programmable logic inputs and two relay outputs for remote monitoring and control.

Typical Applications

This soft starter excels in pumps, fans, compressors, conveyors, crushers, and centrifugal machines. Its bypass design reduces heat dissipation after startup, allowing installation in smaller cabinets without active cooling.

Certifications

CE, UL, cUL, CCC, and GOST certified. Meets EMC standards (IEC 60947-4-2). Environmental rating IP20 (NEMA 1). Operating temperature -10°C to +40°C without derating.

Conclusion

The SND ATS48D38Q combines rugged construction, precise torque control, and extensive protection features. It is a reliable solution for applications demanding smooth starts and stops while minimizing electrical stress on the power system.