Mass store query to OPC DA Server

[inesdahmann]

Hello experts,

I have an application where I write 13 OPC tags to a Siemens S7 PLC, using PCO and an OPC DA server. Currently, it takes about 5 seconds between the first item has arrived on the plc and the last item arrives. On the OPC sever log, I can see that each item is written seperately. According to OPC Server support, the server also supports mass store queries, where all items are written at one in one operation, which should be quite faster than writing each item seperately.

My question now: Can I accomplish this using SAP MII and SAP PCO? Are there special configuration settings that I have to make?

Attached are the current configurations of PCO (Version 15.0.1.2196) OPC source system and the MII (Version 15.0 SP4 Patch10) PCO query I use.

I have one transaction with two PCO queries, one to write the set values for the plc (13 tags) (--> see picture) and one to write a handshake bit (1 tag).  The variable Local.selectedTags in the picture contains the list of the 13 tag names, Local.selectedValues contains the corresponding values.

It would be great if someone can help me to speed up our process.

Best regards,

Ines Dahmann

[inesdahmann · Accepted solution]

The solution was to use a PCO TagFixedQuery instead of a TagStoreQuery in the MII transaction. This writes items to the OPC Server in one operation.

[former_member196557 · Accepted solution]

HI Ines,

Which version if MII are you using to implement the PCoQuery?  MII 15.0 SP5 supports MassStore without having to construct the FixedQuery manually.

Regards, Steve

[inesdahmann · Accepted solution]

Hi Steve,

we are currently on 15.0 SP4.

Just curious and for future reference: In the new SP, does the TagStore automatically do a mass store when there are multiple tags, or do I have to make a special setting on the query? Or is it a new Query mode?

Best regards,

Ines