Description
Product Overview
The ABB REJ601 BD446NN1XG is a numerical feeder protection relay from ABB’s Relion 601 family, intended for overcurrent protection in medium-voltage distribution systems. It monitors current signals from the associated instrument transformers and evaluates them against configured protection settings. When a detected fault meets the applicable trip criteria, the relay can initiate a configured protective response through its output contacts. Typical applications include outgoing feeders, cable circuits, and overhead distribution lines in utility and industrial installations.
The REJ601 family supports phase-overcurrent and earth-fault protection, with additional functions depending on the selected hardware and application configuration. ABB documentation describes options for 1 A or 5 A current-transformer inputs, configurable binary inputs and outputs, event and fault records, and optional serial communication. Where fitted and enabled, communication options include Modbus RTU and IEC 60870-5-103. The REJ601 is the feeder-protection version without the circuit-breaker control functionality associated with the REF601 model.
For the ABB REJ601 BD446NN1XG, the complete ordering code is important: different code combinations can specify different current inputs, binary I/O arrangements, communication options, application configurations, terminal styles, and product versions. The exact feature breakdown for this particular suffix has not been independently confirmed from the available official ordering table, so it should not be inferred from a similar REJ601 variant. Before ordering, compare the complete code and serial label against the installed relay, verify the CT secondary rating and protection settings, and confirm the auxiliary supply and communication requirements. Correct catalog identification is only the first step; protection coordination and commissioning checks remain necessary.
Product Introduction
A feeder relay replacement must match the electrical inputs and protection configuration of the existing switchgear—not just the front-panel model name. The ABB REJ601 BD446NN1XG is designed for numerical overcurrent protection in distribution networks, with additional capabilities determined by its ordering configuration.
Before installation, verify the CT rating, auxiliary supply, terminal arrangement, binary I/O, and communication option. After replacement, qualified protection personnel should validate settings, trip logic, and relay operation against the approved coordination study.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Manufacturer | ABB |
| Product Family | Relion 601 |
| Model | |
| Ordering Code | BD446NN1XG |
| Product Type | Numerical feeder overcurrent protection relay |
| Primary Application | Medium-voltage feeder protection |
| Main Protection | Overcurrent and earth-fault protection |
| Current Transformer Input | 1 A or 5 A options across the product family; confirm exact variant |
| Auxiliary Supply | Product-family documentation lists 24–240 V AC/DC; confirm the exact code and nameplate |
| Binary Inputs / Outputs | Configuration-dependent |
| Communication | Optional Modbus RTU or IEC 60870-5-103 on supported variants |
| Event / Fault Records | Supported by the product family |
| Circuit-Breaker Control | Not the dedicated breaker-control version; see REF601 for that product role |
| Installation | Panel-mounted relay; confirm cutout and terminal details from the applicable manual |
| Firmware / Product Version | Verify from the relay label and configuration records |
| Condition | Confirm stock status, inspection, and test documentation |
The table distinguishes family-level capabilities from details that require confirmation for the exact ordering code. Use the nameplate and the applicable ABB product manual as the final authority for commissioning.
REJ601 BD446NN1XG
Related Products
- ABB REF601 — Feeder protection and control relay; includes circuit-breaker control functionality not provided by .
- ABB REJ603 — Feeder protection relay family for distribution applications; confirm its power arrangement and functions before considering it as a substitute.
- ABB REM601 — Motor protection relay for applications requiring motor-specific protection functions.
- ABB REX615 — Protection and control relay platform for applications that need a different function set and system integration.
- ABB 1 A variant — Relevant where the installed current transformers have 1 A secondary outputs.
- ABB 5 A variant — Relevant where the installed current transformers have 5 A secondary outputs.
- ABB CIM601 communication card — An accessory referenced in /REF601 documentation; confirm compatibility with the exact relay version.
- ABB REF601 communication-enabled variant — A comparison option when serial communication and breaker control are part of the required application.
These are related products or configuration references, not guaranteed direct replacements. Check the full ordering code, protection functions, terminal layout, and current-transformer requirements before selecting an alternative.
Frequently Asked Questions
Q1. What does the ABB BD446NN1XG do?
It is a numerical feeder protection relay intended to detect overcurrent and earth-fault conditions in compatible distribution systems. It evaluates measured current against configured settings and initiates the assigned protective response when trip criteria are met.
Q2. Is interchangeable with REF601?
Not automatically. ABB positions for feeder protection and for feeder protection with circuit-breaker control. Replacing one with the other may affect control wiring, functions, and the approved application design.
Q3. How can I confirm whether this unit accepts 1 A or 5 A CT inputs?
Check the full ordering code and the relay’s nameplate, then compare them with the applicable ABB ordering guide. The product family includes both ratings, and selecting the wrong input variant can produce incorrect measurements and protection behavior.
Q4. Does BD446NN1XG support Modbus RTU or IEC 60870-5-103?
The family offers serial communication options, but the exact protocol depends on the ordering configuration. Do not assume that this specific suffix includes a communication interface. Verify the relay label, installed communication hardware, and configuration documentation before planning integration.
Q5. Can I install this relay without changing the existing protection settings?
Existing settings may be reusable only if the replacement has matching hardware and functional configuration. A qualified protection engineer should verify the settings, CT ratios, trip logic, binary I/O, and coordination requirements before returning the feeder to service.
Q6. How do I verify that a supplied relay is genuine and tested?
Request photographs of the actual unit’s identification labels, serial number, terminals, and enclosure. Ask for traceability details and a written test report specifying which functions were checked. A clean appearance or power-on test alone does not establish full protection performance.
Q7. What condition and warranty should I confirm before ordering?
Ask whether the relay is new surplus, used, or refurbished; whether it has been functionally tested; and what warranty and return terms apply. New-surplus status does not guarantee factory-sealed packaging or a documented protection test. For a protective relay, obtain the available test evidence before treating it as ready for service.
