PlantStruxure PES [V4.2]: During deployment of Control Executable in a M580 HSBY controller, deployment fail with an error "Unable to Synchronize [Engine {IP.EN_US}] due to unknown error. Please try again"

Goals and Symptoms

During deployment of the control project into M580 HSBY controller, it failed with an error not possible to sync the primary and standby. When we try to sync Primary and Standby  from Topology context menu command, an error message appeared as follows.

During this stage Primary keep on Running as Primary and standby in "Running Wait" state.

Facts and Changes

This problem could occur during Full Deployment or Deploy changes in M580 HSBY controller.

Causes and Fixes

When you perform Deploy of Control Executable to M580 from PES, it first deploy the Control application to Primary Controller. On successful completion of deploy in primary, PES execute the command to transfer the application from Primary to Standby. If there are any failure during controller to controller transfer the Deployment will fail. Similarly when the command is executed to Sync Primary to Standby from Topology, the error "Unable to Synchronize [Engine {IP.EN_US}] due to unknown error. Please try again" indicated that there is some problem during controller to controller transfer.

Unlike M340 or Quantum, in M580 HSBY CPU, the controller Mast Task is configured for Periodic Tasks. Which means that Task execution will happen periodically at defined interval. By default this interval (Periodic time) is set to 20ms as set in the Logical Project in PES.

So whenever there is a command issued for Transfer application from Primary to Standby, it is being carried out in the spare Scan time in controller and is being done in multiple scan cycle. For example if the current scan time for the controller is 15 ms and configured period for Mast task is 20 ms then application transfer will happen in last 5ms which is spare Scan time and controller will take multiple scan cycle to complete the transfer of application to Standby.

But if current Scan time is 23 ms for the application but the configured periodic scan time is 20 ms, application is being executed with overrun scan time there will not be any spare time available in controller for housekeeping action such as controller to controller transfer. And eventually the Sync will fail and result in above error.

To resolve the problem you have to adjust the periodic Scan time in Logical project at least 20% more than the current scan time. You can identify the current scan time by looking at CPU Animation Screen in Refine Online. But if you are doing the online modification which is resulting the increase in controller current scan time from the configured Periodic Scan time, you can adjusted the Scan time for controller with some cushion by putting this new Periodic time value in Adjust Period in CPU Animation screen online without stopping the controller. There after you will able to get both the CPU sync properly. The only point need to take care that this Adjust Period setting is only valid till next download. Thus user has to put same value as the Adjust Period in configuration of Periodic Scan time in Mast cycle.

Released for: Schneider Electric Belgium