Schneider ATS48D38Q Altistart 48 Soft Starter: Advanced Motor Control with Integrated Bypass

Product Overview

The Schneider ATS48D38Q is a soft starter belonging to the Altistart 48 series, designed for controlled starting and stopping of three-phase induction motors. This device is rated at 38 amperes for 230V motor applications, providing a compact solution for motor management in industrial and commercial installations. The Altistart 48 series features a patented torque control system that reduces mechanical stress on equipment and electrical stress on the power supply by limiting inrush current and eliminating current spikes. The ATS48D38Q incorporates an integrated bypass contactor that short-circuits the thyristors after the start ramp is completed, reducing heat dissipation and extending product life. The device includes advanced protection functions, communication capabilities, and a user-friendly keypad display for configuration and monitoring.

Key Features of Schneider ATS48D38Q

The ATS48D38Q utilizes Schneider Electric's torque control system (TCS) that provides linear acceleration and deceleration profiles, adapting the motor torque to the load requirements for optimal performance. The integrated bypass contactor eliminates power losses in the thyristors during steady-state operation, allowing the soft starter to be mounted in enclosures with minimal thermal management. The device supports both voltage ramp and current limiting start modes, with configurable start torque, ramp time, and stop ramp time to suit various load types including centrifugal pumps, fans, compressors, and conveyors.

The Altistart 48 soft starter includes comprehensive motor protection functions such as thermal overload protection, phase loss detection, phase imbalance protection, and undercurrent detection for dry-run protection on pumps. The front panel features a backlit graphic display and four navigation buttons, enabling local configuration of parameters, viewing of operational data, and diagnosis of fault conditions. The ATS48D38Q supports multiple communication protocols via optional modules, including Modbus, Ethernet/IP, Profibus DP, and CANopen, allowing integration into automated control systems. The device is rated for standard applications up to 380 V and heavy-duty applications at reduced current ratings.

Technical Specifications

• Manufacturer: Schneider Electric

• Part Number: ATS48D38Q

• Series: Altistart 48

• Product Type: Soft Starter

• Rated Current: 38 A at 230 V

• Motor Power Rating: Up to 15 kW at 230 V (typical)

• Supply Voltage: 208 to 230 V AC ±10%

• Control Supply: 220 to 230 V AC

• Integrated Bypass: Yes

• Start Modes: Voltage ramp, current limiting

• Protection Functions: Thermal overload, phase loss, phase imbalance, undercurrent

• Display: Backlit graphic LCD

• Communication Protocols: Modbus, Ethernet/IP, Profibus DP, CANopen (with option modules)

• Operating Temperature: -10 to +40 °C

• Degree of Protection: IP20

• Certifications: CE, UL, CSA, CCC

Functional Description

The ATS48D38Q soft starter uses six thyristors in anti-parallel configuration to control the voltage applied to the motor during starting. When a start command is received, the control algorithm initially applies reduced voltage to the motor, then gradually increases the voltage over the programmed start ramp time until full line voltage is reached. The torque control system continuously monitors motor current and calculates the actual torque, adjusting the voltage to maintain a linear torque ramp independent of load variations. Once full voltage is achieved, the integrated bypass contactor closes, shunting the thyristors and eliminating their power dissipation. During stopping, the device can be configured for a soft stop (voltage ramp down), freewheel stop, or DC injection braking depending on application requirements. The built-in protection logic continuously monitors motor and starter conditions, and in the event of a fault such as overload or phase loss, the device opens the line contactor and displays the fault code on the front panel LCD.

Applications

The Schneider ATS48D38Q soft starter is deployed in applications requiring controlled acceleration and deceleration of motors in the 15 kW power range at 230V. Typical uses include pumps to eliminate water hammer effects, fans and blowers to reduce belt and bearing stress during startup, compressors to limit inrush current on weak power systems, and conveyors to provide smooth load transfer. The integrated bypass feature makes this soft starter ideal for applications with high duty cycles or frequent starting, as the bypass contactor reduces heat generation and extends component life. The device is suitable for use in water treatment facilities, HVAC systems, food processing machinery, and material handling equipment.