When PLC is not responding the Select command the action is not breaking by ‘Timeout for SBO activation’ and keeps waiting on Select response.

When PLC is not responding the Select command the action is not breaking by ‘Timeout for SBO activation’ and keeps waiting on Select response.

Summary

Issue in Command Processing blocking the response variable (RV) when a faulty or too busy IED does not react on Select command. In 7.11 the command actions were using for SBO the same 'Timeout' period like configured in action for 'Watchdog timer', default 30s. Thus, after send of Select the action was waiting 30s and if there was still no response on Select from device - there was unlockable Interlocking with text "Timeout for SBO activation" and action was finished. Since 7.20 there is no SBO-Timeout anymore. The action waits forever - until communication abort (or Select confirmation). All Watchdog timers are affected. Timeout for Operate works correctly, also missing response on Cancel does not cause locks.

Description

Issue in Command Processing blocking the response variable (RV) when a faulty or too busy IED does not react on Select command. In 7.11 the command actions were using for SBO the same 'Timeout' period like configured in action for 'Watchdog timer', default 30s. Thus, after send of Select the action was waiting 30s and if there was still no response on Select from device - there was unlockable Interlocking with text "Timeout for SBO activation" and action was finished. Since 7.20 there is no SBO-Timeout anymore. The action waits forever - until communication abort (or Select confirmation). All Watchdog timers are affected. Timeout for Operate works correctly, also missing response on Cancel does not cause locks.

Solution

Timeout is now considered correctly.

Information

Note: no response on Select while rest communication exchange still works, means that the IED is faulty or busy, e.g. with long process of internal interlocking checks.

Issue Number: 36943
Fixed on Date: 17.8.2016
Versions: 7.20 0 BUILD 31040