Issue:

The SAGE RTU does not update analog values or statuses, cannot change the clock, and displays a NOCLOCK warning on the web interface. The unit also resets intermittently.

Product:

SAGE Remote Terminal Unit (RTU) all models.

Environment:

• Field-installed SAGE RTUs
• Web interface showing NOCLOCK warning

Cause:

The NOCLOCK message indicates that the firmware is not detecting the 1 millisecond clock interrupt, which is a critical hardware signal. This interrupt acts as the RTU’s primary heartbeat for scheduling tasks. Without it, essential processes such as IO updates and status changes fail. This is not related to the Real Time Clock (RTC) that tracks date and time. The absence of this interrupt typically triggers a forced reboot to make the malfunction visible.

The root cause is usually a hardware issue, such as a damaged or improperly connected component (e.g., baseboard).

Resolution:

• Verify all hardware connections and ensure components are properly seated.
• Inspect for damaged boards or connectors.
• Replace any faulty hardware components.

Released for: Schneider Electric South Africa