Decision Tree: Communication / DCS

← Back to Alarms Hub Alarm Codes → Back to GC8000
Goal: Restore stable updates to DCS / PLC / Historians (values, quality, and update timing).
1) Confirm the analyzer is running analysis normally (latest run time updating).
2) Check network basics: link lights, correct IP / subnet / gateway, and ping from the same network.
3) Verify protocol settings: Modbus TCP / OPC / serial gateway settings match the DCS configuration.
4) Verify mapping: tag / register list, data types, scaling, and quality / status mapping.
5) Confirm update cycle: GC cycle time vs DCS polling time (avoid over-polling causing timeouts).

Quick Symptoms → Likely Cause

All values stale: IP/network issue, service down, wrong protocol port.

Values update but wrong: register offset, scaling, wrong data type.

Bad quality only: quality/status mapping, handshake issue, polling mismatch.