Product Overview

The Schneider ATS22C17S6U is an industrial Altistart 22 soft starter designed for controlled starting and stopping of three-phase asynchronous motors. It is particularly suited to applications where reducing mechanical stress, controlling motor acceleration, and managing starting current are important operational requirements.

The ATS22C17S6U is a North American-oriented version of the Altistart 22 family, featuring a 110 V AC control circuit. Its motor supply range is designed for applications from 208 V to 600 V, making it suitable for a broad range of industrial motor systems.

With a nominal starter current rating of approximately 170 A, the ATS22C17S6U can be applied to motors across several power ratings depending on the actual supply voltage and application conditions. Its published motor ratings include 50 hp at 208 V, 60 hp at 230 V, 125 hp at 460 V, and 150 hp at 575 V.

The unit uses torque-controlled starting with current limited to approximately 3.5 times the configured motor current. It also incorporates an internal bypass function, allowing the soft starter to transition the motor toward normal operating conditions after the starting sequence.

The ATS22C17S6U is commonly considered for pumps, fans, conveyors, compressors, and other industrial machinery where a controlled motor start is preferred over direct-on-line starting.

The supplied physical dimensions are 356 × 150 × 229.5 mm, and the supplied product weight is approximately 18 kg. The device uses forced-convection cooling and is designed for vertical installation within an appropriate electrical control cabinet.

Technical Specifications

What Is the Schneider ATS22C17S6U?

The Schneider ATS22C17S6U is a motor soft starter used to control the acceleration and deceleration of compatible three-phase asynchronous motors.

Unlike a conventional direct-on-line starter, which applies the available motor supply almost immediately, a soft starter manages the electrical conditions during motor acceleration. This allows the motor to build up speed progressively instead of receiving the full starting condition instantaneously.

This is particularly useful for machines where a sudden application of motor torque can create mechanical stress. Pumps, fans, conveyors, and other rotating equipment may benefit from a smoother acceleration profile.

The ATS22C17S6U should not be regarded as a replacement for a variable frequency drive in applications requiring continuous speed adjustment. Its primary function is controlled motor starting and stopping rather than continuous variable-speed operation.

One important characteristic of this model is the 110 V control circuit. This distinguishes the ATS22C17S6U from the ATS22C17S6 version, which uses a different control-voltage arrangement. Therefore, the suffix must be checked carefully when selecting a replacement.

Function and Working Principle

The ATS22C17S6U is installed in the motor supply circuit and controls the motor starting process through its power-control stage.

A simplified system architecture is:

Incoming Three-Phase Supply → Protection → ATS22C17S6U → Motor → Mechanical Load

When the start command is received, the soft starter begins its configured acceleration sequence. The voltage and current applied to the motor are controlled so that the motor can accelerate in a more progressive manner.

The ATS22 family uses torque-controlled starting, with the starting current limited according to the configured application parameters. This helps provide a more predictable starting response than a simple direct connection.

Once the motor reaches the appropriate operating condition, the internal bypass function can reduce the continuous power-processing burden of the starting stage. This allows the motor to operate under normal running conditions while the soft starter remains integrated into the control architecture.

The ATS22C17S6U also provides control and communication functions that allow it to participate in larger automation systems. Its Modbus communication capability can be integrated with suitable PLC, HMI, or supervisory architectures for monitoring and control.

Motor Power Application

The ATS22C17S6U has different motor power capabilities depending on the supply voltage. This is important because soft starter selection should never be based solely on the motor horsepower printed on a general product description.

The actual suitability of the starter must also consider motor rated current, starting duty, load characteristics, starting frequency, ambient temperature, installation conditions, and the required application category.

Role in Industrial Control Systems

The ATS22C17S6U can operate as the motor-starting layer within a PLC-based industrial control system. A PLC or other control device can issue the start and stop commands, while the soft starter manages the electrical starting process.

A complete automation architecture may include:

• PLC controller
• HMI operator panel
• Motor protection equipment
• Circuit breaker or upstream protection
• ATS22C17S6U soft starter
• Three-phase asynchronous motor
• Start and stop control circuits
• Emergency stop system
• Modbus RS485 communication network
• Pump, fan, conveyor, or other mechanical load

Through this arrangement, the PLC can coordinate motor operation with the rest of the machine while the ATS22C17S6U performs the required starting control.

Industrial Applications

Pump Control

Pump motors can generate significant mechanical and hydraulic effects when started abruptly. A controlled start can help the motor and connected pumping equipment accelerate more smoothly.

Industrial Fans

Large fans and blowers often have substantial rotating inertia. The ATS22C17S6U can provide a controlled acceleration profile suitable for applications where full variable-speed control is unnecessary.

Conveyor Systems

Heavy conveyors can experience considerable mechanical stress when started directly. Soft starting can help reduce sudden torque transfer through belts, couplings, shafts, and gearboxes.

Compressors

Industrial compressors can require substantial motor starting power. A properly selected soft starter can help manage the starting process while allowing the compressor to transition into normal operation.

Material Handling Equipment

Material handling machinery often uses large motors connected to mechanical transmission systems. Controlled acceleration can help improve starting behavior and reduce mechanical shock.

HVAC Systems

Large ventilation and air-moving systems may use soft starters for fan motors where controlled starting is required but continuous variable-speed regulation is not part of the application.

OEM Machinery

Machine builders can integrate the ATS22C17S6U into motor-driven equipment when the motor rating and control architecture are compatible with the soft starter.

Installation and System Integration

Correct installation of the ATS22C17S6U requires attention to electrical, mechanical, thermal, and control-system requirements.

Verify the Motor

Check the motor nameplate voltage, current, frequency, horsepower, connection method, and operating duty before selecting and commissioning the soft starter.

Check the Supply Voltage

The ATS22C17S6U is designed for a broad three-phase motor supply range. The actual incoming supply must fall within the permitted range for the selected installation.

Verify the Control Voltage

The S6U version uses a 110 V AC control circuit. This is a critical selection point. The control supply should be verified before energization to prevent incorrect control-voltage application.

Install Suitable Protection

Upstream short-circuit and motor protection equipment should be selected according to the motor, installation, fault conditions, and applicable electrical requirements.

Provide Adequate Cabinet Space

The ATS22C17S6U measures approximately 356 × 150 × 229.5 mm and weighs approximately 18 kg. The cabinet mounting structure should therefore be capable of supporting the unit securely.

Allow Appropriate Ventilation

The device uses forced convection cooling. Adequate airflow and clearance should be maintained around the equipment according to the system design.

Configure Motor Current

The motor-rated-current parameter should be matched to the actual motor. The ATS22 current setting range is adjustable according to the starter rating, allowing the device to be configured for different motor currents within its applicable range.

Configure Starting Parameters

Starting time, torque-related parameters, current limitation, stopping behavior, and other application settings should be adjusted according to the motor and mechanical load.

Test Before Full Production

During commissioning, test the motor at controlled conditions before placing the machine into normal production. Verify rotation direction, acceleration, stopping, current behavior, alarms, and control-system responses.

Compatible System Components

Recommended Alternative Models

When replacing the ATS22C17S6U, the control-voltage suffix must be considered together with motor voltage, current, power, application duty, and communication requirements. Models from the same Altistart 22 family may have different control-voltage arrangements and motor ratings.

Key Advantages

• Designed for three-phase asynchronous motor starting
• Part of the Schneider Altistart 22 soft starter family
• 110 V AC control circuit for S6U applications
• Supports 208…600 V motor supply applications
• 170 A starter current rating
• Torque-controlled starting
• Starting current limited to approximately 3.5 times configured motor current
• Internal bypass function
• Modbus communication through RS485
• Suitable for pumps, fans, conveyors, compressors, and industrial machinery
• Forced-convection cooling
• Compact industrial frame measuring 356 × 150 × 229.5 mm
• Product weight of approximately 18 kg

Technical FAQs

What is the Schneider ATS22C17S6U?

The Schneider ATS22C17S6U is an Altistart 22 soft starter designed for controlled starting and stopping of three-phase asynchronous motors.

What is the control voltage of the ATS22C17S6U?

The ATS22C17S6U uses a 110 V AC control circuit. This is one of the important characteristics distinguishing the S6U version from other ATS22 variants.

What motor voltage can the ATS22C17S6U support?

The model is designed for three-phase motor supply applications from approximately 208 V to 600 V, subject to the applicable system and operating conditions.

What is the current rating of the ATS22C17S6U?

The starter has an IcL rating of approximately 170 A. The actual motor-rated-current setting must be configured according to the connected motor and application.

What horsepower motors can be used with the ATS22C17S6U?

Typical published ratings include 50 hp at 208 V, 60 hp at 230 V, 125 hp at 460 V, and 150 hp at 575 V. Actual selection should be based on motor current and application duty rather than horsepower alone.

Does the ATS22C17S6U have an internal bypass?

Yes. The model includes an internal bypass function as part of its Altistart 22 design.

Does the ATS22C17S6U support Modbus?

Yes. The ATS22C17S6U provides Modbus communication through an RS485 serial interface, allowing suitable PLC, HMI, or supervisory systems to exchange information with the soft starter.

What are the dimensions of the ATS22C17S6U?

The dimensions are approximately 356 × 150 × 229.5 mm.

How much does the ATS22C17S6U weigh?

The product weight is approximately 18 kg.

What is the difference between ATS22C17S6U and ATS22C17S6?

The most important difference for system integration is the control-voltage configuration. The S6U version uses a 110 V AC control supply, while the S6 version uses a different control-voltage arrangement. Therefore, the complete model number should always be checked before replacement.

Is the ATS22C17S6U a variable frequency drive?

No. It is a soft starter. It is primarily intended to control motor acceleration and stopping rather than provide continuous variable-frequency speed control.

What applications are suitable for the ATS22C17S6U?

Typical applications include pumps, fans, conveyors, compressors, material-handling equipment, HVAC systems, and other industrial motor-driven machinery.

Conclusion

The Schneider ATS22C17S6U Soft Starter is a high-capacity Altistart 22 motor-control device designed for controlled starting and stopping of three-phase asynchronous motors. Its combination of a broad 208…600 V supply range, approximately 170 A starter rating, torque-controlled starting, internal bypass, and Modbus RS485 communication makes it suitable for a wide range of industrial motor applications.

One of the most important characteristics of this model is its 110 V AC control circuit, which makes the S6U suffix particularly important when selecting or replacing equipment. Engineers should not assume that another ATS22 model with a similar current rating is electrically interchangeable without checking the control-voltage requirements.

The supplied physical dimensions are approximately 356 × 150 × 229.5 mm, and the product weight is approximately 18 kg. Proper cabinet support, ventilation, wiring, protection, and commissioning procedures should therefore be incorporated into the installation design.

For system integrators, electrical engineers, OEM machine builders, and maintenance technicians, the ATS22C17S6U provides a practical solution for applications requiring smoother motor acceleration without the continuous speed-control functionality of a variable frequency drive. When correctly matched to the motor, supply, load, and control system, it can contribute to more controlled motor starting and improved overall machine operation.