SEL Protocol Client Configuration in RTAC
Key Takeaway
How to configure the RTAC as a SEL protocol client to poll SEL relays for relay word bits, metering, events, and target states over serial connections.
Quick Answer
The RTAC polls SEL relays using ASCII SEL protocol commands over RS-232 or RS-485 serial ports. Extracted data includes relay word bits (BOOL), metering values (REAL), target states, SER events, and oscillographic event reports — all stored in the RTAC tag database.
Configuration
- Add SEL protocol client driver
- Configure serial port (baud rate matching relay, typically 9600+)
- Add relay device (model, access level password)
- Configure poll rate (fast for critical, normal for metering)
Data Extraction
- TAR — Target states (which elements operated)
- MET — Phase currents, voltages, power, frequency, energy
- DNA — Device identification
- SER — Sequential events recorder entries
- EVE — Oscillographic fault records
Tag Mapping
Relay word bits → BOOL tags. Metering values → REAL tags. Multiple relays on one RS-485 bus polled sequentially.
See SEL communications protocols for protocol details.
Need help with scada & programming?
Texas-based licensed engineers — get a free, no-obligation assessment.
Frequently Asked Questions
Via SEL proprietary ASCII protocol over RS-232 or RS-485 serial, periodically sending commands and parsing responses into the RTAC tag database.
Relay word bits (Boolean status), metering (currents, voltages, power), targets, SER events, and oscillographic event reports.
Still have questions about your setup? Talk to an engineer or call (210) 405-4248.