ABB T5S-400/PR221/R320 Tmax T5S 400A Fixed Circuit Breaker with PR221 Electronic Trip Unit

ABB documentation identifies the corresponding configuration as T5S400 R320 with a 320 A rated current, fixed installation, front connection arrangement and PR221 electronic protection. The T5S 400/630 family is specified with a 50 kA short-circuit breaking capacity at 415 V.

Product Identification

• Manufacturer: ABB
• Product Family: Tmax T5S
• Frame Size: T5S 400
• Configuration: T5S-400/PR221/R320
• Rated Current: 320 A
• Trip Unit: PR221
• Installation: Fixed
• Product Category: Molded Case Circuit Breaker
• Application: Low-Voltage Electrical Protection

ABB Tmax T5S Overview

The ABB Tmax T5S series is part of the Tmax family of low-voltage circuit breakers designed for electrical distribution and protection applications. The T5S frame covers 400 A and 630 A configurations, with the applicable rating determined by the selected circuit-breaker configuration.

For the R320 configuration, the circuit breaker has a rated current of 320 A. ABB’s product documentation lists T5S400 R320 configurations with different electronic trip units, including PR221DS-I and PR221DS-LS/I.

The T5S designation also identifies a higher short-circuit performance level than the corresponding T5N version. ABB documentation specifies 50 kA at 415 V for the T5S 400/630 family.

PR221 Electronic Trip Unit

The PR221 is the electronic trip-unit family used with compatible ABB Tmax circuit breakers. It provides electronic protection functions rather than relying solely on a conventional thermal-magnetic release.

ABB documentation shows the T5S400 R320 configuration with PR221DS-I and PR221DS-LS/I variants. The exact protection functions therefore depend on the complete PR221 configuration specified with the breaker.

When identifying an installed breaker, the complete trip-unit designation should be checked because PR221 configurations can differ in available protection functions.

R320 Rated Current

The R320 designation identifies the 320 A rated-current configuration of the T5S 400 frame. ABB’s product tables list T5S400 R320 with an In value of 320 A.

The rated-current value is an important part of the circuit-breaker identification because the same T5S 400 frame can also be configured with R400.

Consequently, T5S400 R320 and T5S400 R400 should not be treated as identical configurations even though they share the same basic T5S 400 frame.

50 kA Short-Circuit Rating

ABB specifies the T5S 400/630 family with a short-circuit breaking capacity of 50 kA at 415 V. This distinguishes the T5S version from the T5N version, which ABB lists at a lower short-circuit rating.

The short-circuit rating is an important consideration when selecting a molded case circuit breaker for an electrical distribution system. The actual application must remain within the applicable voltage, current and short-circuit parameters of the complete installation.

Fixed Installation

The ABB T5S400 R320 configuration is identified in ABB documentation as a fixed circuit breaker. The product tables distinguish fixed installation from other installation arrangements available within the broader Tmax product range.

A fixed circuit breaker is installed in a permanent position within the electrical distribution equipment. This configuration is appropriate for switchboards and panels where the breaker does not need to be withdrawn during normal operation.

Front Connection Arrangement

ABB’s configuration tables identify the T5S400 R320 PR221 variants with front connection arrangements.

The connection arrangement is an important specification when matching the breaker with an existing switchboard or electrical panel because terminal orientation and connection accessories must correspond to the physical installation.

Technical Specifications

Protection Functions

The PR221 electronic trip system provides the protection functions associated with the selected PR221 configuration. ABB’s documentation lists both PR221DS-I and PR221DS-LS/I variants for the T5S400 R320 frame.

The designation of the trip unit is therefore important when specifying protection characteristics. A breaker identified only as T5S400 R320 does not necessarily describe the complete electronic protection configuration.

For replacement or engineering purposes, the trip-unit marking should be compared with the original equipment documentation.

PR221DS-I Configuration

ABB lists PR221DS-I as one of the electronic trip-unit configurations available with the T5S400 R320 breaker. The ABB product tables identify this configuration with a 320 A rated current.

The PR221DS-I designation is associated with electronic instantaneous protection. The exact trip characteristics should be determined from the applicable ABB technical documentation for the specific release.

PR221DS-LS/I Configuration

ABB also lists PR221DS-LS/I for the T5S400 R320 configuration. This version provides a broader electronic protection arrangement than the basic instantaneous configuration.

When ordering or identifying a replacement, the complete PR221 designation should therefore be checked carefully.

Electrical Distribution Applications

The ABB T5S 400 circuit breaker is intended for low-voltage electrical distribution and protection applications. Its 320 A rated-current configuration makes it suitable for distribution circuits where the system design requires this current rating.

The T5S short-circuit performance also makes the breaker suitable for installations where a 50 kA short-circuit capacity at the applicable voltage is required.

Typical applications can include industrial switchboards, distribution panels, motor-related distribution systems, and other low-voltage electrical installations.

Industrial Power Protection

Molded case circuit breakers are commonly used to protect electrical circuits against abnormal current conditions. The ABB Tmax T5S architecture combines the mechanical switching structure with an electronic trip unit to provide controlled protection.

The PR221 electronic release allows protection settings and characteristics to be determined according to the selected release version and system requirements.

The correct protection settings should always be determined from the electrical design of the installation.

Selection Considerations

Several identification parameters should be considered when selecting an ABB T5S circuit breaker. These include the frame size, rated current, trip-unit type, number of poles, installation method, terminal arrangement and required short-circuit performance.

For the configuration discussed here, the key parameters are T5S 400, R320, and PR221.

The number of poles must also be confirmed separately because ABB documentation provides both three-pole and four-pole configurations for the T5S400 family.

Three-Pole and Four-Pole Versions

ABB’s product tables show T5S400 R320 configurations in both three-pole and four-pole versions. For example, the PR221DS-I configuration is associated with different ordering references depending on whether the breaker is three-pole or four-pole.

Therefore, the generic designation T5S-400/PR221/R320 should not be used as the only reference when determining the exact ordering number. The pole configuration and connection arrangement should also be verified.

ABB Ordering References

ABB historical product documentation lists the T5S400 R320 PR221DS-I configuration under ordering references 054 334 for three-pole and 054 342 for four-pole versions. The PR221DS-LS/I configuration is listed under 054 332 and 054 340, respectively.

Later ABB ordering references use the 1SDA numbering structure. For example, the three-pole T5S400 R320 PR221DS-LS/I configuration is identified as 1SDA054332R1 in ABB-related product listings.

This distinction is useful when comparing an older product designation with a later ABB article number.

Maintenance and Replacement

For maintenance purposes, the breaker should be identified from the complete marking on the device. The frame size, rated current, trip-unit designation, pole count and connection arrangement should all be recorded.

A breaker with the same T5S 400 frame but a different rated-current configuration or trip unit may not provide the same electrical characteristics.

The correct replacement should therefore match the complete original configuration rather than relying only on the T5S 400 frame designation.

System Integration

The ABB T5S-400/PR221/R320 is designed to operate as part of a low-voltage electrical distribution system. Its protection characteristics must correspond to the downstream and upstream equipment, conductor ratings, prospective short-circuit current and system voltage.

The fixed installation arrangement and front connection configuration should also correspond to the mechanical design of the electrical panel.

Engineering personnel should verify all applicable electrical parameters before installation or replacement.

Product Identification Summary

Online Product Identification

A suitable technical product name for an industrial automation and electrical equipment catalogue is:

ABB T5S-400/PR221/R320 Tmax T5S 400A Fixed Molded Case Circuit Breaker

Useful search variations include ABB T5S-400/PR221/R320, ABB T5S400 R320, ABB T5S 400 PR221, ABB Tmax T5S R320, ABB PR221 R320, and ABB T5S400 320A Circuit Breaker.

Part Number and Configuration Verification

ABB documentation confirms the T5S400 R320 configuration with PR221 electronic trip units. The T5S 400/630 family is rated at 50 kA short-circuit capacity at 415 V, while the R320 configuration corresponds to a 320 A rated current.

Because the exact ordering reference changes according to pole count and PR221 variant, these details should be checked against the physical breaker before using a specific ABB article number.

Conclusion

The ABB T5S-400/PR221/R320 is a configuration of the ABB Tmax T5S low-voltage molded case circuit breaker family. It combines the T5S 400 frame with a 320 A R320 rated-current configuration, fixed installation and PR221 electronic protection. ABB documentation specifies a 50 kA short-circuit rating at 415 V for the T5S 400/630 family.

The complete identification should include the trip-unit variant and pole configuration when determining the exact ordering reference. This is particularly important because ABB lists separate three-pole and four-pole references and different PR221 configurations for the T5S400 R320 frame.