How to write or find diagnostic for S7 400H and ET 200 SP Interface with IO Modules?

 Hi Fritz, 

Can you please guide me how to write or find diagnostic for S7 400H and ET 200 SP Interface  with IO Modules, 

Thanks

Kumar

fritz

Hello olliman

olliman

But can you confirm if manipulating this will affect the time from a network brake untill I detect offline with SFC51?

Allwo me to quote theoffical definition fromthe manual first:
The watchdog time is the time interval that an IO controller or IO device permits, without receiving IO data.
If the IO device is not supplied by the IO controller with data within the watchdog time, the device detects the missing frames and outputs substitute values.
This is reported in the IO controller as a station failure.
In STEP 7, the watchdog time is made up from an integral multiple of the update time and can be set by the user.

So yes, manipulating this will affect the time (via manipulation of the "number of accepted update cycles with missing IO data")from a network break untill you detect an"offline" IO devicewith SFC51.

olliman

So with your pic as an example, it would take 6 ms from network brake untill SFC51 detects it (omitting cycle time as a factor)?

Correct, but please note the following:
My example pic is just an example pic and you wouldn't use 6ms as the Watchdog for a H-system with System redundantly connected IM153-4's.

For MRP (not your case) you need to for example set it to at least 200ms, see also What should you watch out for when parameterizing the watchdog time when a ring redundancy is established with the Media Redundancy Protocol? for more on this.

You though presumably use the so called "System redundancy".
While I thought I sawa valueof 30ms being stipulated somewhere for the changeover time from one CPU to another in case of a network break, I unfortunately can't find the reference for this anymore (not in a hurryanyhow).
I suggest you do a search through manuals to verify and/orperhaps someone else out there may know for sure.
Either way,youneed to be mindful of this whendeciding on the Watchdog value.

I hope this helps

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Split from S7-400H Profinet IO node time-out time.