Product Overview

The Schneider ATS22D75S6 Soft Starter is an industrial motor starting and stopping device from the Schneider Electric Altistart 22 series. It is designed for controlled acceleration and deceleration of three-phase asynchronous motors, particularly in applications where reducing starting stress is important for both the motor and the driven machinery.

Unlike a direct-on-line starter, which applies the available supply voltage to the motor immediately, the ATS22D75S6 progressively controls the motor during startup. This approach helps limit starting current and reduces sudden torque, helping protect mechanical components such as shafts, couplings, belts, gearboxes and pump assemblies.

The ATS22D75S6 has a 75 A starter rating and is intended for three-phase motor applications across a broad supply range. Its standard application range includes motor power from approximately 15 to 25 kW at 200–240 V, 30 to 50 kW at 380–440 V, and 30 to 50 kW at 480–500 V. It uses a 230 V AC control circuit and is suitable for applications such as pumps and fans.

The soft starter also provides an internal bypass, Modbus communication through an RS-485 interface, three discrete inputs and two relay outputs. Its compact industrial enclosure measures 295 × 145 × 207 mm and has a product weight of approximately 12 kg.

Technical Specifications

Function and Working Principle

The primary function of the ATS22D75S6 is to provide controlled motor starting and stopping.

A conventional direct-on-line starter can cause a motor to draw a high current immediately after energization. The resulting torque can also be transferred directly to the mechanical load.

The ATS22D75S6 uses electronic control to progressively increase the motor voltage during startup.

The basic system arrangement is:

Three-Phase Power Supply

↓

ATS22D75S6 Soft Starter

↓

Three-Phase Induction Motor

↓

Industrial Equipment

During acceleration, the starter controls motor torque while limiting the starting current to approximately 3.5 times the motor current under the specified starting method.

This controlled process can reduce:

• Starting current
• Mechanical shock
• Belt tension
• Coupling stress
• Gearbox impact
• Shaft torsion
• Pump pressure fluctuations
• Equipment vibration

The ATS22D75S6 can also provide controlled stopping for applications where an abrupt motor stop is undesirable.

Role in Industrial Control Systems

The ATS22D75S6 functions as the motor-starting controller between the electrical power system and the motor.

A typical industrial configuration is:

Power Distribution

↓

Circuit Breaker / Protection

↓

ATS22D75S6

↓

Three-Phase Motor

↓

Pump / Fan / Compressor / Conveyor

A PLC can provide start and stop commands to the soft starter, while the ATS22D75S6 manages the motor acceleration process.

This arrangement separates process control from motor starting control, allowing the automation controller to manage production sequences while the soft starter handles the electrical characteristics of motor startup.

The integrated Modbus communication interface also allows the ATS22D75S6 to be incorporated into a larger industrial communication system.

Motor Power and Electrical Characteristics

The 75 A starter rating places the ATS22D75S6 within the higher-current models of the smaller ATS22 frame range.

Typical motor power applications include:

The actual motor selection should always be based on the motor’s rated current, voltage, load characteristics, starting conditions and installation configuration rather than motor power alone.

Industrial Applications

The Schneider ATS22D75S6 can be used in a wide variety of industrial motor-control applications.

Typical applications include:

• Industrial pumps
• Centrifugal pumps
• Water treatment systems
• Wastewater equipment
• Cooling-water systems
• Industrial fans
• HVAC equipment
• Ventilation systems
• Air compressors
• Conveyor systems
• Material handling machinery
• Packaging equipment
• Manufacturing machinery
• Process equipment
• Mining machinery
• General factory automation

The model is particularly useful for fixed-speed motor applications where controlled starting is required but continuous variable-speed regulation is not necessary.

Pump Applications

Pump motors can generate substantial mechanical and hydraulic stress when started abruptly.

A typical pump control system using the ATS22D75S6 can be arranged as:

PLC

↓

ATS22D75S6

↓

Three-Phase Motor

↓

Pump

↓

Process Fluid

The progressive starting process helps the pump reach operating speed more smoothly.

This can be beneficial in:

• Water supply systems
• Industrial water circulation
• Wastewater treatment
• Cooling systems
• Process pumping
• Industrial fluid transfer

Controlled acceleration can help reduce sudden pressure changes and mechanical loading throughout the pump system.

Fan and Blower Applications

Large industrial fans and blowers may have significant rotational inertia.

A sudden motor start can place additional stress on:

• Motor bearings
• Fan shafts
• Couplings
• Belts
• Gearboxes
• Mounting structures

The ATS22D75S6 provides a controlled acceleration process, allowing the rotating assembly to reach operating speed progressively.

This makes it suitable for industrial ventilation, HVAC and process-air systems.

Conveyor and Material Handling Applications

Conveyor systems often require smooth acceleration to prevent sudden belt loading.

Direct starting can result in:

• Belt slippage
• Product displacement
• Gearbox shock
• Coupling stress
• Excessive belt tension

The ATS22D75S6 helps provide a more controlled startup, which can improve conveyor reliability and reduce mechanical stress.

For large material-handling systems, the soft starter can therefore become an important part of the motor-control architecture.

Internal Bypass Function

The ATS22D75S6 incorporates an internal bypass function.

During startup, the solid-state section regulates the motor voltage. Once normal operating conditions are reached, the internal bypass can reduce continuous conduction losses in the semiconductor control section.

This can help limit heat generation during normal operation.

For control cabinets containing multiple electrical devices, reducing unnecessary heat dissipation can make cabinet thermal management easier.

Communication and Control

The ATS22D75S6 supports Modbus communication using an RS-485 multidrop interface.

The communication connection uses an RJ45 connector.

This provides an option for connecting the soft starter to a PLC, supervisory system or other compatible industrial automation equipment.

Typical communication applications include:

• Motor status monitoring
• Fault monitoring
• Remote supervision
• Parameter management
• Centralized motor control
• Industrial diagnostics

The ATS22D75S6 also provides:

• 3 discrete inputs
• 2 relay outputs
• 1 PTC probe input

These interfaces allow the soft starter to be integrated into both hardwired and networked control architectures.

Protection and Monitoring

The ATS22D75S6 includes protection functions for monitoring the operating condition of the motor and starter.

Important protection areas include:

• Line phase failure
• Motor thermal protection
• Starter thermal protection
• Starting condition monitoring
• Motor current monitoring
• Fault status
• Operating status

A 750 Ω PTC probe input can be used for compatible motor thermal monitoring applications.

These functions provide additional information for troubleshooting and preventive maintenance.

Installation and System Integration

Mechanical Installation

The ATS22D75S6 measures:

295 × 145 × 207 mm

and has a product weight of:

12 kg

The unit is intended for vertical installation, with an allowable operating position of approximately ±10°.

Because the soft starter uses forced convection cooling, adequate ventilation space should be maintained around the unit.

Electrical Installation

A typical installation includes:

• Three-phase incoming power
• Motor output connections
• Protective grounding
• Control circuit
• Motor protection
• PLC control wiring
• Modbus communication wiring when required

Correct cable sizing, protection and grounding are important for reliable operation.

Installation and Commissioning

A practical commissioning procedure includes:

1. Verify the ATS22D75S6 model.
2. Confirm the motor voltage.
3. Confirm motor rated current.
4. Check the motor power.
5. Verify the 230 V control circuit.
6. Install the starter vertically.
7. Connect incoming three-phase power.
8. Connect the motor.
9. Verify protective grounding.
10. Configure the motor parameters.
11. Configure the acceleration settings.
12. Configure stopping parameters.
13. Verify PLC control signals.
14. Perform an initial startup.
15. Monitor motor current.
16. Check acceleration behavior.
17. Test under normal load.
18. Verify protection functions.
19. Confirm communication if Modbus is used.

The final configuration should always correspond to the actual motor and driven load.

Compatible System Components

The ATS22D75S6 can be integrated with the following types of industrial equipment.

Maintenance and Troubleshooting

Regular maintenance can help ensure reliable operation of the ATS22D75S6.

Recommended checks include:

• Inspect power terminals.
• Check motor wiring.
• Verify grounding.
• Inspect cooling passages.
• Check forced-air circulation.
• Remove excessive dust.
• Inspect control wiring.
• Check Modbus connections.
• Monitor motor current.
• Review fault indications.
• Check motor starting behavior.
• Verify configuration parameters.

Particular attention should be given to cooling airflow in environments with high ambient temperatures or significant dust accumulation.

Common Fault Conditions

Before replacing the soft starter, the motor, power supply, control circuit and mechanical load should all be inspected.

Recommended Alternative Models

For a replacement project, the ATS430D75S6 is a particularly relevant newer-generation option for a 75 A application. However, voltage range, control supply, motor characteristics, wiring and application requirements should be checked before making a direct replacement.

Key Advantages

• Schneider Electric Altistart 22 soft starter
• Designed for three-phase asynchronous motors
• 75 A starter rating
• 230–500 V AC supply range
• 230 V AC control circuit
• Torque-controlled starting
• Starting current limited to approximately 3.5 × motor current
• Internal bypass
• Modbus communication
• RS-485 interface
• RJ45 communication connector
• Three discrete inputs
• Two relay outputs
• 750 Ω PTC probe input
• Forced-convection cooling
• IP20 protection
• Vertical installation
• Suitable for pumps and fans
• Suitable for compressors and conveyors
• Dimensions: 295 × 145 × 207 mm
• Weight: 12 kg

Technical FAQs

What is the Schneider ATS22D75S6?

The ATS22D75S6 is an Altistart 22 soft starter designed for controlled starting and stopping of three-phase asynchronous motors.

What is the rated current?

The ATS22D75S6 has a 75 A starter rating.

What supply voltage does it support?

The model is designed for a 230–500 V AC three-phase supply range, with applicable motor power varying according to supply voltage.

What is the control voltage?

The control circuit voltage is 230 V AC.

What motor power can it handle?

Typical motor power ranges include 15–25 kW at 200–240 V, 30–50 kW at 380–440 V, and 30–50 kW at 480–500 V, subject to the actual application and installation conditions.

Does the ATS22D75S6 have an internal bypass?

Yes. The soft starter incorporates an internal bypass function.

Does it support Modbus communication?

Yes. The ATS22D75S6 provides Modbus communication through an RS-485 interface.

What are the dimensions?

The dimensions are 295 × 145 × 207 mm.

How much does it weigh?

The product weight is approximately 12 kg.

Is the ATS22D75S6 a variable frequency drive?

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

What applications are suitable for this model?

The ATS22D75S6 is suitable for pumps, fans, compressors, conveyors, ventilation systems and other industrial applications using three-phase asynchronous motors.

What is the difference between ATS22D75S6 and ATS22D75S6U?

Both are 75 A Altistart 22 soft starters, but their control supply configurations differ. The ATS22D75S6 uses a 230 V control circuit, while the ATS22D75S6U uses a 110 V control circuit. They should therefore not be treated as electrically identical replacements.

What should be checked before replacing an ATS22D75S6?

The motor voltage, rated current, motor power, control voltage, load characteristics, starting conditions, protection equipment, communication requirements and cabinet installation should all be verified.

Conclusion

The Schneider ATS22D75S6 Soft Starter is a reliable solution for controlled starting and stopping of medium-power three-phase asynchronous motors. Its 75 A starter rating, broad 230–500 V AC supply range, 230 V AC control circuit, internal bypass and Modbus communication make it suitable for integration into a wide range of industrial motor-control systems.

The controlled starting function helps reduce electrical inrush current and mechanical shock, making the ATS22D75S6 especially useful for pumps, fans, compressors, conveyors and other fixed-speed industrial machinery.

With dimensions of 295 × 145 × 207 mm and a weight of 12 kg, the unit is suitable for vertical installation in industrial control cabinets and motor control centers.

For maintenance engineers, system integrators and industrial automation professionals, the ATS22D75S6 provides a practical motor-starting solution that combines controlled acceleration, motor protection, communication capability and industrial-grade construction. For newer system designs, the ATS430D75S6 can be evaluated as a modern 75 A alternative, while the complete electrical and application requirements should always be checked before replacement.