Description
Product Introduction
REF543 is ABB’s feeder terminal for protection, control, measurement, and supervision in medium-voltage networks. It handles feeders, motors, and capacitor banks across single/double busbar and duplex switchgear configurations.
The unit integrates PLC logic, supports multiple protocols (IEC 60870-5-103, Modbus, LON, SPA bus), and offers 25 binary inputs with 18 output relays. IEC 61850 is available through the SPA-ZC 400 adapter, though note that REF543 is not an active product since 2022.
Frequently Asked Questions
Q: Does it support hot-swapping?
A: Honestly, no. This is a feeder protection relay tied to trip circuits and CT/VT inputs. You must isolate the bay, disable trip outputs, and follow lockout-tagout before removing the unit.
Q: Is it obsolete? Are there direct replacements?
A: Yes—ABB discontinued REF543 in 2022. In our experience, the upgrade path is to the REF545 or newer MV relay families, but you’ll need to re-validate settings, I/O mapping, and communication configuration.
Q: Will I lose my program during replacement?
A: The most common mistake is assuming the new unit loads the same logic automatically. Back up all setting groups, PLC logic, disturbance records, and communication configs before removal, then restore and verify point by point.
