Invalid Timestamp Handling in IEC 60870-5-104 Driver within AVEVA Telemetry Server

In an energy remote control system, we are using the AVEVA Telemetry Server to read/write data from PLCs via the IEC 60870-5-104 protocol. During analysis of the communication frames, we have observed that, in some cases, values are received with the Invalidity bit set, yet the timestamp is still passed transparently to the OMI. This results in invalid timestamps being displayed alongside valid ones, without any filtering or correction by the driver.

This behavior has led to alarms being acknowledged with timestamps earlier than their actual activation time. In a critical energy management environment, this can cause serious operational inconsistencies and safety concerns.

According to section 7.2.6.3 of the IEC 60870-5-104 protocol (Quality Descriptor), values marked as invalid should not be forwarded to SCADA. If a valid value has an incorrect timestamp, the Telemetry system should assign a correct timestamp before passing it on.

The proposed workaround—delegating timestamp validation to internal SCADA scripts—is not viable. It shifts protocol compliance responsibility away from the driver and imposes unnecessary processing load on the SCADA system. This approach is inappropriate for a critical infrastructure like energy control.

We kindly request that AVEVA consider implementing proper handling of invalid timestamps within the IEC 60870-5-104 driver, in compliance with the protocol standard. The success of our project depends on this feature being available.