ABB SPACOM replaces REX615

From SPACOM to REX615: A Complete Technical Guide for Relay Modification

The lifecycle management of protective relays is a continuous challenge in the fields of power systems and industrial distribution. With the gradual discontinuation of the SPACOM series relays, many users are facing issues such as spare parts shortages, technical support, and termination of firmware updates. ABB's Relay Retrofit Program for SPACOM to REX615 provides a systematic solution to this dilemma. This article elaborates on how to use this renovation plan from an engineering practice perspective to smoothly replace the original SPACOM protection relay with the latest REX615 relay, covering the entire process of selection, mechanical installation, electrical wiring, configuration and debugging.

Why is it necessary to modify: End of Life for SPACOM Relays

The SPACOM series relays have been widely used in the protection, control, and monitoring of medium and low voltage distribution systems over the past few decades. Common models include sub series such as SPAA, SPAC, SPAD, SPAF, SPAJ, SPAM, SPAS, SPAU, etc. However, with the evolution of ABB's product line, these relays have entered a state of discontinuation. Continuing to use old relays will bring the following risks:

Difficult to obtain spare parts: unable to replace quickly after a malfunction, prolonging power outage time.

Insufficient communication capability: SPACOM relays often use traditional hard wired or serial protocols, making it difficult to integrate into the digital substation (IEC 61850) architecture.

Maintenance support terminated: firmware updates, fault diagnosis, and calibration services will no longer be provided.

Mechanical wear: After long-term operation, the reliability of the internal contacts, display screen, and power module of the relay decreases.

ABB's renovation plan aims to extend the overall lifespan of the switchgear by replacing it with REX615 relays, while providing full lifecycle service support. This solution not only restores the original protection function, but also adds new features such as status monitoring, advanced communication, and programmable logic as needed.

REX615: Technological advantages of replacing relays

REX615 belongs to the ABB Relion product family and is an integrated protection and control relay. Its design is compact and adopts a withdrawable unit structure, which is easy to maintain and test. Compared to SPACOM, REX615 has the following significant advantages:

2.1 Comprehensive communication protocol support

REX615 natively supports IEC 61850 (including Edition 1 and 2.1), IEC 60870-5-103, IEC 104, Modbus, and DNP3. This means that it can seamlessly integrate into modern substation automation systems, enabling GOOSE communication, SCADA remote control, and fault recording upload.

2.2 Higher protection performance

By using digital signal processors and algorithms, the protection action time is shorter and the accuracy is higher. Simultaneously supporting configurable protection function blocks, users can flexibly activate corresponding protection components according to application requirements (feeders, transformers, motors, etc.).

2.3 Enhanced Monitoring and Diagnosis

Built in circuit breaker wear monitoring, trip circuit monitoring, environmental temperature recording and other status monitoring functions provide data support for predictive maintenance.

2.4 Unified Engineering Tools

Using PCM600 (Protection and Control IED Manager) for configuration, setting values, and fault analysis, the same tool can manage the entire Relion series of relays, reducing training costs.

Compatible SPACOM models

The renovation plan currently supports SPACOM relay models covering a wide range of sub series. According to the document, the following models already have corresponding REX615 replacement plans (more models will be added in the future):

SPAA series: SPAA 120 C, SPAA 121 C, SPAA 341 C, SPAA 110 C, SPAA 115 C, SPAA 130 C, SPAA 131 C, SPAA 135 C, SPAA 140 C, SPAA 141 C, SPAA 142 C, SPAA 144 C, SPAA 160 C, SPAA 330 C, SPAA 331 C

SPAC series: SPAC 310 C, SPAC 312 C, SPAC 315 C, SPAC 317 C

SPAD Series: SPAD 346 C

SPAF series: SPAF 140 C

SPAJ series: SPAJ 110 C, SPAJ 111 C, SPAJ 115 C, SPAJ 131 C, SPAJ 135 C, SPAJ 140 C, SPAJ 141 C, SPAJ 142 C, SPAJ 144 C, SPAJ 160 C

SPAM Series: SPAM 150 C (NO/NC)

SPAS Series: SPAS 120 C

SPAU series: SPAU 110 C, SPAU 121 C, SPAU 130 C, SPAU 140 C, SPAU 330 C, SPAU 331 C

Before starting the renovation project, users should verify the complete model of the existing SPACOM relay and select the corresponding replacement kit in the ABB order code.

Content and selection of renovation kit

The deliverables provided by the renovation plan include not only the REX615 relay itself, but also a series of installation accessories and engineering services to ensure efficient and accurate on-site operations.

4.1 Standard Includes Items

REX615 relay: Pre configured (corresponding to the original SPACOM function) or empty configuration can be selected at the factory.

Modification connector kit: includes X100 (24 pin), X110 (24 pin), or X130 (18 pin) connectors, as well as a protective ground wire (2 meters long, 6mm ², with M4 ring terminals on both ends), X120 stickers, M3 × 8mm screws (T10).