Description
Product Core Brief
- Model: REF541
- Order Code: REF541KM115AAA
- Brand: ABB
- Series: REF54_ feeder protection terminal family
- Core Function: Protection, control, measurement, monitoring and power quality functions for medium-voltage feeders.
- Product Type: Feeder protection terminal / MV feeder IED
- Key Specs: Phase and earth-fault protection | Voltage and frequency protection | Power quality measurement | Disturbance recorder | Local HMI | Communication interface
- Condition: New Original / New Surplus, depending on stock
Product Introduction
ABB REF541KM115AAA is a medium-voltage feeder protection terminal from the ABB REF54_ family. It integrates protection, control, measurement, status monitoring and power quality functions in one device, making it suitable for MV switchgear, distribution substations and industrial power systems.
The REF541 family supports non-directional and directional overcurrent and earth-fault protection, residual voltage, overvoltage and undervoltage protection, thermal overload protection, circuit-breaker failure protection and auto-reclose. It also provides measurement of phase currents, phase and residual voltages, frequency, power factor, active/reactive power and energy, together with THD measurement and short-time voltage variation monitoring.
The order code REF541KM115AAA identifies a specific hardware and software variant within the REF541 family. Public listings do not provide a complete decoding of this exact code, so the auxiliary voltage, I/O count, communication option and software version should be verified against the device nameplate and order documentation before replacement.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Brand | ABB |
| Model | REF541 |
| Order Code | |
| Product Type | MV feeder protection terminal |
| Typical Application | Medium-voltage distribution feeders and switchgear |
| Protection Functions | Overcurrent, earth-fault, voltage, frequency, thermal overload, CBFP, auto-reclose |
| Measurement | Current, voltage, frequency, power, energy, THD, voltage sags/swells |
| HMI | Local graphical display / MIMIC interface |
| Communication | Serial/Ethernet depending on configuration; IEC 61850, IEC 60870-5-103, DNP3, Modbus, Profibus-DPV1, LON possible on selected variants |
| Condition | New Original / New Surplus |
Quality Control Process
- Full order code verification: Confirm REF541KM115AAA matches the original nameplate.
- Visual inspection: Check front HMI, terminal blocks, communication ports, mounting hardware and signs of overheating.
- Nameplate confirmation: Verify auxiliary voltage, CT/VT ratings, I/O configuration and software version.
- Secondary injection test: Confirm overcurrent, earth-fault, voltage and frequency protection settings.
- Communication test: Verify SCADA protocol, address mapping and remote readback.
- Packing: Anti-static bag, moisture barrier, rigid corner protection and reinforced carton.
Replacement Pitfall Guide
❗ Confirm the full order code. REF541KM115AAA defines a specific variant; other REF541 codes may differ in auxiliary power, I/O, communication or software version.
❗ Do not assume identical function from model alone. The REF54_ family includes REF541, REF543 and REF545 with different I/O counts and function sets.
❗ Verify CT/VT and protection settings. Wrong ratios, pickup values or time delays can cause nuisance trips or failure to clear faults.
❗ Check communication compatibility. Protocol, baud rate, address map and SCADA point list must match the existing system.
❗ Avoid blind replacement. Feeder protection terminals are safety-critical; replacement should follow site commissioning and testing procedures.
Keep these in mind and you’ll cut 90% of rework time.
Compatibility Matrix & Benchmarks
| Original Model | Replacement / Successor Model | Compatibility Level | Migration Notes |
|---|---|---|---|
| ABB | ABB | Direct | Match full order code, firmware and configuration. |
| ABB | ABB REF541 other order code | Needs Verification | Same family but different I/O, communication or software. |
| ABB | ABB REF615 / REF620 / REF640 | Needs Verification | Newer feeder protection family; panel cutout, wiring and engineering may differ. |
| ABB | Generic MV protection relay | Needs Verification | Requires engineering review of I/O, protection logic and communication. |
Benchmarks:
- ABB REF54_ medium-voltage feeder protection terminal family.
- Supports overcurrent, earth-fault, voltage, frequency and thermal overload protection with measurement, disturbance recording and power quality functions.
