Product Overview

The Schneider ATS22D88S6U Soft Starter is an industrial motor-control device from the Schneider Electric Altistart 22 series. It is designed to provide controlled starting and stopping for three-phase asynchronous motors in industrial automation, process equipment, infrastructure systems, and general motor-control applications.

When a large induction motor is connected directly to a power supply, the motor can produce a high starting current and a sudden increase in mechanical torque. These conditions can place additional stress on electrical distribution equipment and mechanical components such as shafts, couplings, belts, gearboxes, pumps, and fans.

The ATS22D88S6U addresses this problem by controlling the motor starting process. Instead of applying the full motor voltage immediately, the soft starter provides a controlled acceleration profile that allows the motor to reach operating speed more progressively.

The ATS22D88S6U has an 88 A starter rating and is designed for three-phase AC motor applications. Its rated supply range is 208–600 V AC, making it suitable for a broad range of industrial motor systems.

One of the most important characteristics of this model is its 110 V AC control circuit. This specification should be checked carefully when selecting the device for an existing control cabinet because other ATS22 models may use different control-voltage configurations.

The ATS22D88S6U also provides an integrated bypass function, Modbus communication capability, RS-485 connectivity, discrete control inputs, relay outputs, and motor-temperature monitoring capability.

With dimensions of 295 × 145 × 207 mm and a weight of approximately 12 kg, the unit is designed for industrial control cabinets and motor-control installations.

Technical Specifications

Function and Working Principle

The main function of the ATS22D88S6U is to control the starting and stopping process of a three-phase asynchronous motor.

A conventional direct-on-line starter applies the available supply voltage directly to the motor. For larger motors, this can generate a high inrush current and considerable starting torque.

The ATS22D88S6U uses controlled motor starting to provide a more gradual acceleration process.

A simplified system arrangement is:

Three-Phase AC Supply

↓

ATS22D88S6U Soft Starter

↓

Three-Phase Asynchronous Motor

↓

Industrial Mechanical Load

During startup, the ATS22D88S6U regulates the motor starting process according to the configured parameters. The starting current can be limited to approximately 3.5 times the motor current under the appropriate operating conditions.

This approach can reduce the electrical and mechanical impact associated with direct motor starting.

The controlled starting process can help reduce:

• High starting-current demand
• Mechanical shock
• Shaft stress
• Coupling stress
• Belt tension
• Gearbox loading
• Pump pressure surges
• Fan vibration
• Conveyor shock

The device can also provide controlled stopping when the application requires a gradual reduction in motor operation.

What Is the Schneider ATS22D88S6U Used For?

The ATS22D88S6U is designed for applications where a motor normally operates at a fixed speed but requires a smoother starting and stopping process.

It is not primarily intended for continuous speed regulation. Instead, it acts as a controlled motor starter between the electrical supply and the motor.

Typical applications include:

• Industrial water pumps
• Centrifugal pumps
• Process pumps
• Cooling pumps
• Industrial fans
• Blowers
• Ventilation systems
• Compressors
• Conveyor systems
• Material-handling equipment
• Cooling systems
• Manufacturing machinery
• Process equipment
• General industrial automation

The model is particularly useful when direct-on-line starting causes excessive current, mechanical impact, belt movement, pressure fluctuations, or equipment vibration.

Role in Industrial Control Systems

The ATS22D88S6U can be installed as part of a complete motor-control architecture.

A typical system can be arranged as follows:

Main Power Supply

↓

Circuit Breaker / Protection

↓

ATS22D88S6U Soft Starter

↓

Three-Phase Motor

↓

Pump / Fan / Compressor / Conveyor

The PLC can provide start and stop commands to the soft starter, while the ATS22D88S6U manages the motor-starting process.

This arrangement allows the automation controller to focus on process logic while the soft starter manages motor acceleration and stopping.

For larger industrial systems, the ATS22D88S6U can also communicate with the control system through its Modbus interface.

This can allow information such as motor operating status and fault conditions to be incorporated into the plant automation system.

Motor Power and Electrical Characteristics

The ATS22D88S6U has an 88 A starter rating.

Its typical motor power capability varies according to the motor supply voltage.

Motor selection should not be based on horsepower alone.

Before selecting the ATS22D88S6U, engineers should verify:

• Motor rated current
• Motor rated voltage
• Motor power
• Load inertia
• Starting time
• Starting frequency
• Ambient temperature
• Mechanical load
• Cabinet cooling conditions

The motor’s rated current should remain within the applicable operating capability of the soft starter.

Industrial Applications

Pump Applications

The ATS22D88S6U is well suited to pump systems that require gradual acceleration.

Common applications include:

• Water treatment pumps
• Water supply systems
• Cooling-water pumps
• Wastewater systems
• Process-fluid pumps
• Industrial circulation pumps
• Centrifugal pumps

Controlled starting can reduce sudden pressure changes and mechanical stress in the pumping system.

Fan and Blower Applications

Industrial fans and blowers can have considerable rotational inertia.

A controlled start can reduce mechanical stress on:

• Fan shafts
• Bearings
• Couplings
• Belts
• Gearboxes
• Motor assemblies

This makes the ATS22D88S6U suitable for industrial ventilation and air-handling equipment.

Compressor Applications

The ATS22D88S6U can also be applied to compatible compressor motors.

Potential applications include:

• Industrial air compressors
• Screw compressors
• Process compressors
• Factory compressed-air systems

The starting characteristics of the compressor should be considered when configuring the soft starter.

Conveyor Applications

Conveyors often require controlled acceleration to avoid sudden belt movement.

The ATS22D88S6U can help provide a smoother startup for:

• Belt conveyors
• Material-handling equipment
• Packaging machinery
• Production-line conveyors
• Industrial transport systems

Internal Bypass Function

The ATS22D88S6U incorporates an internal bypass function.

During the motor-starting process, the soft starter controls the motor through its power-control section. Once the motor reaches the required operating condition, the bypass function can reduce the continuous losses associated with electronic power switching.

This can reduce heat generation within the control cabinet.

The integrated bypass also helps simplify the overall motor-control arrangement because an additional external bypass contactor may not be required for the standard bypass function.

Communication and Control

The ATS22D88S6U supports Modbus communication through an RS-485 interface.

The communication connection uses an RJ45 connector.

This provides a practical method of connecting the soft starter to a PLC or other industrial automation controller.

Typical applications include:

• Motor status monitoring
• Fault monitoring
• Remote supervision
• Operating-state monitoring
• Parameter management
• PLC integration
• Centralized motor monitoring
• Maintenance diagnostics

The soft starter also provides:

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

These interfaces allow the ATS22D88S6U to operate in both hardwired control systems and networked automation systems.

Protection and Monitoring

The ATS22D88S6U provides integrated monitoring and protection functions for motor-control applications.

Important monitoring areas include:

• Motor thermal condition
• Soft-starter thermal condition
• Motor current
• Phase-related conditions
• Starting conditions
• Fault status
• Operating status

A compatible PTC temperature probe can also be used for motor temperature monitoring.

These functions are useful for industrial applications where the motor operates continuously or where unexpected motor shutdown can affect production.

Installation and System Integration

Mechanical Installation

The ATS22D88S6U dimensions are:

295 × 145 × 207 mm

The specified weight is:

12 kg

The unit is designed for vertical installation and uses forced-convection cooling.

Adequate space should be maintained around the soft starter to allow sufficient airflow.

The installation environment should also be considered, particularly when the control cabinet is exposed to:

• High ambient temperature
• Dust
• Moisture
• Restricted airflow
• Continuous high motor loading

Electrical Installation

A typical electrical installation includes:

• Three-phase incoming power
• Motor output connections
• Protective grounding
• 110 V AC control supply
• PLC control wiring
• Motor protection equipment
• Modbus communication wiring where required

The 110 V AC control voltage is one of the most important specifications to verify during installation.

Installation and Commissioning

A typical commissioning procedure for the ATS22D88S6U includes:

1. Verify the model number.
2. Confirm the motor voltage.
3. Confirm the motor rated current.
4. Verify the motor power.
5. Confirm the 110 V AC control supply.
6. Install the soft starter vertically.
7. Connect the incoming three-phase supply.
8. Connect the motor.
9. Verify protective grounding.
10. Configure motor parameters.
11. Configure acceleration parameters.
12. Configure stopping parameters.
13. Check the discrete control inputs.
14. Check relay outputs.
15. Configure Modbus communication if required.
16. Perform an initial motor startup.
17. Monitor motor current.
18. Check motor acceleration.
19. Test the motor under normal load.
20. Verify protection and fault functions.

The final configuration should always be based on the actual motor and mechanical load.

Compatible System Components

The ATS22D88S6U can be integrated with several types of electrical and automation components.

The exact component combination depends on the electrical design and application.

Maintenance and Troubleshooting

Regular inspection can help maintain stable operation of the ATS22D88S6U.

Recommended maintenance tasks include:

• Inspect power terminals.
• Check motor wiring.
• Verify grounding.
• Inspect cabinet ventilation.
• Check cooling airflow.
• Remove accumulated dust.
• Inspect control wiring.
• Check communication wiring.
• Monitor motor current.
• Review fault indications.
• Check acceleration behavior.
• Verify configuration parameters.

Particular attention should be given to cabinet temperature and ventilation in continuous-duty applications.

Common Fault Conditions

Before replacing the soft starter, the complete motor-control circuit should be inspected.

Recommended Alternative Models

The ATS22D88S6 can be considered when a 230 V control circuit is available, while the ATS22D88S6U is intended for systems requiring 110 V AC control.

For modernization projects, a newer-generation soft starter can also be evaluated, but the replacement should be checked for motor current, supply voltage, control voltage, communication requirements, mounting dimensions and application characteristics.

Key Advantages

• Schneider Electric Altistart 22 series
• 88 A starter rating
• Three-phase asynchronous motor control
• 208–600 V AC supply range
• 110 V AC control circuit
• Torque-controlled starting
• Starting current limitation
• Approximately 3.5 × motor-current starting limit
• Integrated bypass
• Modbus communication
• RS-485 interface
• RJ45 communication connection
• Three discrete inputs
• Two relay outputs
• PTC temperature monitoring
• Motor thermal protection
• Starter thermal protection
• Phase-related protection
• Forced-convection cooling
• IP20 protection
• Vertical installation
• Suitable for pumps
• Suitable for fans
• Suitable for compressors
• Suitable for conveyors
• Suitable for material-handling equipment
• 295 × 145 × 207 mm
• 12 kg

Technical FAQs

What is the Schneider ATS22D88S6U?

The ATS22D88S6U is an 88 A Altistart 22 soft starter designed to provide controlled starting and stopping for three-phase asynchronous motors.

What is the rated current of the ATS22D88S6U?

The starter rating is 88 A.

What supply voltage does the ATS22D88S6U support?

The rated three-phase supply range is 208–600 V AC.

What is the control voltage?

The ATS22D88S6U uses a 110 V AC control circuit.

What motor sizes are typically associated with this model?

Typical applications include motors rated around 25 HP at 208 V, 30 HP at 230 V, 60 HP at 460 V and 75 HP at 575 V, depending on the application and operating conditions.

Does the ATS22D88S6U have an internal bypass?

Yes. The soft starter incorporates an integrated bypass function.

Does the ATS22D88S6U support Modbus?

Yes. It supports Modbus communication through an RS-485 interface.

What are the dimensions of the ATS22D88S6U?

The dimensions are 295 × 145 × 207 mm.

How much does the ATS22D88S6U weigh?

The specified weight is 12 kg.

Is the ATS22D88S6U a variable frequency drive?

No. It is a soft starter, not a variable frequency drive. It controls motor starting and stopping rather than providing continuous motor-speed regulation.

What is the difference between ATS22D88S6U and ATS22D88S6?

The primary difference is the control circuit voltage. The ATS22D88S6U uses 110 V AC control, while the ATS22D88S6 uses 230 V AC control.

What is the difference between ATS22D88S6U and ATS22D88Q?

These are related 88 A Altistart 22 soft-starter models, but their electrical configurations differ. The control circuit and application configuration should be checked carefully before considering one model as a substitute for the other.

What applications are suitable for the ATS22D88S6U?

It is suitable for fixed-speed industrial motor applications such as pumps, fans, compressors, conveyors, blowers, ventilation systems and material-handling equipment.

Can the ATS22D88S6U be used with a PLC?

Yes. The ATS22D88S6U can be integrated into PLC-based systems using its discrete control interfaces and Modbus communication capabilities.

Conclusion

The Schneider ATS22D88S6U Soft Starter is an 88 A industrial motor-control device designed to provide controlled acceleration and stopping for three-phase asynchronous motors.

Its 208–600 V AC supply range, 110 V AC control circuit, torque-controlled starting, integrated bypass, Modbus communication and industrial protection functions make it suitable for a wide range of motor-control applications.

The ATS22D88S6U is particularly useful for pumps, fans, compressors, conveyors and other fixed-speed industrial equipment where uncontrolled motor starting can produce excessive electrical current or mechanical stress.

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

For maintenance engineers, system integrators and industrial automation specialists, the most important selection characteristics are the 88 A rating, 208–600 V AC supply range and 110 V AC control voltage. The control voltage is particularly important when distinguishing the ATS22D88S6U from closely related Altistart 22 models.

When replacing or integrating this soft starter, engineers should verify the motor rated current, supply voltage, control voltage, starting conditions, mechanical load, communication requirements and cabinet installation conditions to ensure reliable long-term operation.