ATS48 Soft Starter Series Overview

The ATS48 series is a line of soft-start and soft-stop units from Schneider Electric, designed for controlling three-phase squirrel-cage induction motors.

• Primary Function: It provides controlled torque for smooth motor acceleration and deceleration, leveraging a patented Torque Control System (TCS) .

• Key Features:

  • Motor Protection: Includes comprehensive motor thermal protection, underload/overload protection, and phase loss detection .

  • Communication: Integrated Modbus serial communication is standard, with options for other protocols like Profibus DP, DeviceNet, and Ethernet .

  • Configuration: Supports dual motor settings and can be configured via a built-in keypad, remote display, or PC software like PowerSuite/SoMove .

• Typical Applications: Widely used in various machinery and industries, including pumps, fans, compressors, conveyors, and HVAC systems in buildings, food & beverage, and chemical industries .

The ATS48 series is recognized for its ability to reduce mechanical stress on equipment and minimize inrush currents, thereby enhancing system reliability and lifespan .

Overview

The ATS48 is a fully featured, high-performance soft starter from Schneider Electric’s TeSys family, designed for controlling and protecting 3-phase asynchronous AC motors. It is renowned for its robustness, advanced control features, and comprehensive protection suite, making it suitable for a wide range of industrial applications like pumps, fans, conveyors, and crushers.

Key Technical Specifications

Here are the primary technical specifications categorized for clarity:

1. Electrical Specifications

• Supply Voltage:

  • Standard Models: 208V – 575V AC, 50/60 Hz.

• Control Voltage:

  • Integrated within the main power supply for most standard functions. Separate control voltage options are available for specific model variants or for maintaining control logic during a power dip.

• Motor Power Range (at 400V/50Hz):

  • The ATS48 series covers a wide range, typically from ~4 kW (5.5 HP) to 630 kW (850 HP). The specific model number (e.g., ATS48C17Q) indicates the current rating.

• Current Ratings:

  • Available in multiple current ratings, from 17 A up to 1200 A, to match various motor sizes.

• Starting Torque:

  • Adjustable, typically from 20% to 100% of full load torque.

2. Performance & Control Features

• Control Method: Voltage ramp control with an internal torque control algorithm for smooth acceleration and deceleration.

• Starting Modes:

  • Voltage Ramp: Standard linear acceleration.

  • Current Limit: Limits inrush current to a user-defined maximum.

  • Torque Control: Provides smooth starts even under variable load conditions (e.g., crushers).

  • Pump Control / Pump Stop: Specialized algorithms to eliminate water hammer in pump applications.

• Stopping Modes:

  • Coast Stop: Free run.

  • Soft Stop: Controlled deceleration via a voltage ramp.

  • Pump Stop: Specifically designed deceleration for pumps.

  • DC Injection Braking: Provides rapid stopping with a DC current.

• Power Factor Correction (PFC):

  • Integrated capability to control power factor correction capacitors directly, preventing damage to the capacitors.

3. Protection Features

The ATS48 includes a comprehensive set of motor and system protection functions:

• Overload Protection (Class 10): Protects the motor from thermal damage due to excessive current.

• Phase Loss Protection (Input & Output): Detects missing phases.

• Undercurrent / Overcurrent Protection:

• Jam Protection: Detects a locked rotor condition.

• Thermistor Input (PTC): Direct connection for motor winding temperature sensors.

• Short-Circuit Protection: With specially designed semiconductor fuses.

• Phase Reversal Protection: Prevents motor from starting if phases are reversed.

• Motor Pre-heating: Applies a small current to prevent moisture buildup in the motor when idle.

4. Communication & Control

• Integrated Communication Ports:

  • Modbus: A built-in RS-485 serial port for Modbus RTU communication, allowing for integration into SCADA and PLC systems.

  • TeSys Ethernet (on certain models): Some newer or upgraded models offer an embedded Ethernet port for connectivity to industrial networks.

• Inputs/Outputs (I/O):

  • Digital Inputs: Multiple programmable logic inputs (e.g., Run, Stop, Forward, Reverse, Preset Speeds).

  • Relay Outputs: Several programmable relay outputs for status signals (e.g., Ready, Running, Fault, Warning).

  • Analog Input: Can be used for speed or torque reference.

  • Analog Output: Can be configured to output a signal proportional to a measured parameter (e.g., motor current, motor thermal state).

5. Physical & Environmental Specifications

• Enclosure Rating:

  • Typically IP00 (open-type for panel mounting) or IP20 (with a cover) as standard. Higher IP ratings are available with optional kits.

• Ambient Temperature:

  • Storage: -40°C to +70°C (-40°F to +158°F).

  • Operation: -20°C to +60°C (-4°F to +140°F) without derating. Up to +70°C (+158°F) with derating.

• Standards & Certifications:

  • Complies with major international standards such as UL, CE, cULus, and IEC.

6. Key Differentiators

• Advanced Control Algorithms: Particularly its torque control for demanding applications.

• Integrated Bypass Contactor: Internal bypass contactors reduce heat generation and improve efficiency during run state.

• Comprehensive Connectivity: Built-in Modbus and optional Ethernet simplify integration.

• Application-Specific Functions: Features like Pump Control/Stop make it ideal for water and wastewater applications.

Applications of the Schneider Electric ATS48 Soft Starter

The Schneider Electric ATS48 soft starter is a robust and versatile solid-state controller designed primarily for managing the starting and stopping of three-phase asynchronous AC motors. Its primary function is to provide a smooth, controlled acceleration and deceleration, replacing the harsh mechanical and electrical stress caused by direct-on-line (DOL) starting.

Here are the key application areas for the ATS48 soft starter:

1. Pump Control
This is one of the most common applications. The ATS48 effectively eliminates the water hammer effect in piping systems. By gradually increasing the pump’s speed and torque, it prevents sudden pressure surges that can damage valves, pipes, and fittings. This leads to reduced maintenance, lower leakage rates, and increased system longevity.

2. Fan and Blower Control
For centrifugal fans and blowers, the ATS48 soft start prevents sudden torque jolts that can strain belts, bearings, and the fan structure itself. The controlled start reduces high inrush current, which is especially important for large fans, and minimizes mechanical shock to the entire drive train.

3. Conveyor Systems
In material handling, the ATS48 is ideal for starting conveyor belts smoothly. This prevents:

• Load Spillage: Jerky starts can cause materials to fall off the belt.

• Belt Damage: Sudden tension stretches and damages belts and splices.

• Mechanical Shock: It protects gearboxes, rollers, and motors from excessive wear.

• Some models also offer a “Pump Stop” function, which can be used for controlled deceleration to prevent material rollback on inclined conveyors.

4. Compressor Applications
For piston, screw, and centrifugal compressors, the soft starter reduces the massive inrush current required to start the motor against a loaded condition. This minimizes voltage dips in the electrical supply and reduces the mechanical stress on the compressor’s crankcase, pistons, and rods.

5. Mixers, Agitators, and Crushers
These applications often involve high-inertia loads that are difficult to start. The ATS48 provides the high starting torque necessary to get the load moving smoothly, without drawing the excessively high current of a DOL start. This is crucial for protecting the motor and mechanical components from severe stress.

6. General Industrial Machinery
The ATS48 is widely used in various other machines where controlled starting and stopping are beneficial, such as:

• Saws and cutting machines

• Grinders

• Presses

• Extruders

In summary, the Schneider Electric ATS48 soft starter is applied wherever there is a need to:

• Reduce motor inrush current, preventing voltage dips and allowing for the use of smaller supply transformers and protective devices.

• Minimize mechanical stress on the motor, drive train (belts, gears, couplings), and the driven machine, leading to less downtime and lower maintenance costs.

• Eliminate water hammer in pump systems.

• Provide smooth, controlled acceleration and deceleration for process stability and safety.

• Improve operational efficiency and extend the lifespan of electromechanical systems.