A01774 — SI Motion P1 (CU): Test stop for fail-safe digital outputs required

A01774 is raised by the Safety Integrated monitoring (SI Motion P1) of the Control Unit (CU). The drive expects the fail-safe digital outputs (F-DO) to be proven at regular intervals by a forced checking procedure — a test stop. When the monitoring time set in p10003 has elapsed without such a test, the alarm signals that a new forced checking procedure is due. The manuals describe the code identically for the G130/G150 and the S120/S150, so the behaviour is the same on all four families. The message does not result in a safety stop response.

• The time set in p10003 for the forced checking procedure (test stop) for the fail-safe digital outputs (F-DO) has been exceeded, so a new forced checking procedure is required.
• The test must be performed within a defined, maximum time interval — p10003, a maximum of 8760 hours — in order to comply with the requirements laid down in the standards for timely fault detection and with the conditions for calculating the failure rates of the safety functions (PFH value).

1. Carry out the forced checking procedure for the digital outputs.
2. Select the forced checking procedure via the signal source that is set at binector input p10007.
3. Keep the interval between test stops within the time set in p10003 (maximum 8760 hours); if operation continues beyond this maximum period, it is permissible only if it can be ensured that the test is performed before persons enter the hazardous area who are depending on the safety functions correctly functioning.

• p10003 — SI TM54F forced checking procedure timer: holds the monitoring time whose expiry raises A01774; the manual limits it to a maximum of 8760 hours.
• p10007 — BI: SI TM54F forced checking procedure F-DI/F-DO signal source: the binector input via which the signal source that selects the forced checking procedure is set.

No acknowledgment is needed. As soon as the forced checking procedure is selected again via the signal source in p10007, the message withdraws itself and the monitoring time is reset. Until then the alarm stays present, but it does not result in a safety stop response.