Rotork Valve (Profibus) Acyclic data development using siemens S7

[Shane O Sullivan]

Hi all,

I could use a little bit of help. I am currently developing a standard block for a Rotork valve which is to communicate to a S7-300 PLC via Profibus. The problem that I am having is that the customer wants to extract more information using the Acyclic features available on profibus.

I have only used basic (standard) profibus functions, so the acyclic element is very confusing.

any help/advise/useful tips on developing acyclic functions or if anyone has had any experience on Acyclic functions for Rotork valves, it would be hugely appreciated.

Cheers
Shane

 

[RheinhardtP]

I will point you in the right direction you can use SFB 52 or SFC 59. RD_REC. There are loads of information available on the siemens website on this. These are used across multiple devices.

Good luck

 

[Shane O Sullivan]

Many thanks for your reply, I have since been looking at this in depth and found those instructions coming up time and time again. You reply has now confirmed that I am looking in teh right direction. so I am going to have a go with these and see where I get to.

 

[dchartier]

SFC 52 and SFC 59

Hello Shane;
Is the Rotork valve controller a DPV1 slave?
Read_REC and WR_REC instructions will only work if the slave has been programmed to transfer data records acyclicaly, that is, if it has been formatted as a DPV1 slave by the manufacturer.
And of course the DP-master must be DPV1 also (most recent S7 CPUs are).
What model are you using, and does the manual/datasheet specify it as a DPV1 (or DPV0)Profibus-DP slave?
Hope this helps,
Daniel Chartier

 

[Shane O Sullivan]

I have just managed to locate the manual for DP communications. The does state DP-V1 communications. We are using an S7-318 processor. So I am assuming that this is all very possible.