Safety SM326 SF reintegration after power shutdown

Marcjan

Hello,

When power shutdown occurs, after power comes back the SF led on the safety modules blink

I wonder why modules are passivated at power up?
Using a safety input for reintegration, can give trouble if the module is passivated, so yes you can use a standard input but do not use the same reset button that operators use, because you need to know first why there was a fault on 1 or more modules before reintegration.

Regards,

Marcjan

Hi,

See the relevant extract from the"S7 Distributed Safety - configuring and programming Programming and Operating Manual, 07/2013, A5E00109537-05" manual:

"Reintegration of F-I/O
Reintegration of the F-I/O, that is, the provision of process data in the PII or the transfer of
process data provided in the PIQ to the fail-safe outputs, takes place automatically, starting
at the earliest with the second cycle of the F-run-time group after startup of the F-system;
this happens regardless of the setting at variable ACK_NEC. Depending on the F-I/O you are
using and the cycle time of the F-run-time group and PROFIBUS DP/PROFINET IO, several
cycles of the F-run-time group can elapse before reintegration occurs.
If communication between the F-CPU and F-I/O takes longer to establish than the monitoring
time set in the object properties for the F-I/O in HW Config, automatic reintegration does not
take place."

based on the above extract, I think the reason why the HW not reintegrate is one of the follows:

1.The card lost its power while the F-CPU was online.

2.The F-CPU have problem to build up the stabil connection the F-DI after startup.

By the way I think you should not use standard IO to reintegrate or reset any safety functions. There are safety mechanisms prepared to this for you, better use them instead.

Maybe that is separate topic, but can someone enlight me why I see it in many forums? Is it a common practice?

I am wating for comments on this.

Cheers

MicroMan

By the way I think you should not use standard IO to reintegrate or reset any safety functions. There are safety mechanisms prepared to this for you, better use them instead.

Maybe that is separate topic, but can someone enlight me why I see it in many forums? Is it a common practice?

I don't agree with you, there is no need to use F-DI for acknowledge, reset, contactor feedback,etc.. you can alsousenon-safety variables in the safety program for this kind of use.

F-DI have to be used for use with safety switches, F-DO for safety contactors,....for the rest normal IOs are used. This is not different in comparison with hardware of safety relays, you have channels for safety and the rest (feedback, reset button, etc) are standard eqiupment.

If you wish you can put safetyequipmentforeverything, but the price of your machinecan not competewith machine with regular (minimal needed) safety elements.