SEL Real Time Automation Controller (RTAC) Overview
Key Takeaway
What the SEL RTAC is — substation data concentrator, protocol gateway (SEL/DNP3/Modbus/IEC 61850/ICCP), IEC 61131-3 automation controller, and NERC CIP security platform.
Quick Answer
The SEL RTAC (Real Time Automation Controller) is a substation automation controller that aggregates data from multiple relays via SEL protocol, DNP3, Modbus, and IEC 61850, presents it to the SCADA master, and runs IEC 61131-3 control logic for substation automation. Platforms include SEL-3530, SEL-3555, and SEL-3354.
Functions
- Protocol gateway — SEL ↔ DNP3 ↔ Modbus ↔ IEC 61850 ↔ ICCP
- Data concentrator — Aggregates data from multiple relays to one SCADA point
- Automation controller — IEC 61131-3 logic (Ladder, ST, FBD, SFC)
- HMI web server — Local substation operator display
- Event log aggregator — Centralized event collection
Programming
ACSELERATOR RTAC (SEL-5033) provides IEC 61131-3 programming. Common languages: Structured Text and Function Block Diagram. See Allen-Bradley ST and Ignition for cross-platform comparison.
Applications
- Substation data concentration for utility SCADA
- Automatic bus transfer (ABT)
- Load shedding automation
- Volt/VAR optimization
Frequently Asked Questions
Substation data concentration, protocol gateway translation, IEC 61131-3 automation logic, and local HMI — bridging relays to SCADA.
All five IEC 61131-3 languages: Ladder, Structured Text, FBD, SFC, and Instruction List.
Yes. Common application: IEC 61850 MMS client reading modern IEDs while presenting data to a legacy DNP3 SCADA master.