Reading Multiple Parameters via message function

Morning,

I have some source code from a ControlLogix Processor where they used a message function set as CIP Generic, service code 4b, class 93 to read (and write) multiple parameters from a Powerflex 40p via Ethernet.

I've tried searching on the RA knowledgebase for info but can't find anything on it.

I'm trying to use the same set up on a CompactLogix but am getting error 0008 - Unsupported service requested.

Anyone know if this not available on Compact Logix or have I done something wrong?

Cheers for reading...

why massege???
you can add this powerflex in the IO tree of Controllogix in the Rslogix5000.There this will generate Bunch of tag.use that one...But For the massaging you have to see instance attribute...Check here.....http://literature.rockwellautomation.com/idc/groups/literature/documents/um/20comm-um010_-en-p.pdf

I believe he's done it like that as the parameters are stored and can be written back to the inverter if it needs to be replaced.

That sounds like a Scattered Read function.

What it does is deliver a list of parameters to the drive, with the service request "read all these parameters and reply back".

The reply is a list of parameters interspersed with the parameter values.

When you're using a PowerFlex that has 32-bit parameters the space between the parameters is 2 Word, but I think for a PowerFlex with 16-bit parameters it's 1 word.

So the request for parameters 10, 11, and 12 is something like:


and the reply is something like

10
123
0
11
456
0
12
789
0

Click to expand...

The "Service Not Supported" error either comes because the drive you're targeting doesn't support Scattered Parameter Reads, or because the payload doesn't contain a usable list of parameters.

What exact model of drive and interface module (and their firmware revisions) are you using ?

I would be very surprised if the difference was CompactLogix / ControlLogix.

There's a good RA Knowledgebase document that gives an example of Scattered Read with a PowerFlex 4. It's Article ID # 453620 (Access Level: Everyone).

That article shows the Service Code as 0x32.

I don't have a list of CIP Generic service codes handy... try the 0x32 if you're using a 22-COMM-E.

I looked at the 22-COMM-UM004 and it shows Services 0x32 and 0x33 for Scattered Read and Scattered Write, when used with Class 0x93 (DPI Parameter Object).

That's on page C-27.

Service 0x4B is context sensitive. When you use it with the Class 0x0F Parmeter Object, it means "Get_Enum_String". When you use it with the Class 0x67 PCCC Object, it means "Execute PCCC Command".


So I think that Service 0x32 is what you want to try, when used with the DPI Parameter Object.

Hi Ken (and others), thanks for you replies.

I got called out on a breakdown so haven't been on this until this afternoon.
In answer to your questionsPowerflex40P (22-D4P0N104) with 22-COM-E Ethernet adaptor.

I have done more digging while on site and found out they were powerflex70 inverters on the job that worked.

In answer to other questions yes, as you say there is a 66 INT request data area along the lines of:

41
0
0
42
0
0 etc.

then a 66 INT response data area along the lines of:

0
0
0
0
0
0 etc.

For the PF70 inverters and control logix as said they use service code 4b, class 93, instance 0, attribute 0.

I will now have a read of the datasheet you kindly put the link to and see if I can learn about getting any further with the PF40's.

Thanks for your time so far.

After reading the link you posted it has helped a lot (I originally did a search on RA for 'multiple parameter read powerflex40p' and it came up with nothing).

Anyhow I have now got the read function using service 32 working fine, but service 33 (write) isn't as yet, (same error - service not supported).

Still I am a lot further forward than I was the other day :nodi:

OK peeps

all working now,

a quick update for anyone finding themselves with this setup in the future.

the issue was parameter scattered write is service 34 not 33.

And for Powerflex 40's there only needs to be 1 pad word between requested parameter numbers

Cheers