profibus on ControlLogix help

[Iamjonscranium]

i am running an SST profibus scanner with a ControlLogix PLC. I have so many questions that i dont think i could discuss them all here, so i'll just ask 1 for now.

my i/o, automatically setup by the scanner, looks like this
Local1:c
Local1:i
Local1
Local1:s
i changed the i/o from reading/writing Ints to reading/writing Dints (data[1] as int is now data[0], bits 16-32 as dint). do i also need to change the status also?

the PB scanner setup looks like this in rslogix 5000:
assembly
instance
input 1 125
ouput 2 124
config 3 0
statusin 5 125
statusout 6

 

[Iamjonscranium]

also, any tips from anyone who has connected profibus to rslogix would be appreciated. thank you.

 

[jde777]

where did you change the int to dint?
in the controller tags or in the module config when added to the io tree in rslogix 5k?

http://www.pccweb.com/LibraryItems/Documentation/Woodhead/pfb_clx_v1.4.pdf

If you did it in just the tags this is incorrect. delete the module from the io tree and reconfigure it as dint if that is what you want. It is recommended to use int with status.

 

[Iamjonscranium]

i've already set up a new module with Dint's. this is my configuration in rs5000. each is 32-bit.

the PB scanner setup looks like this in rslogix 5000:
assembly
instance
input 1 125
ouput 2 124
config 3 0
statusin 5 125
statusout 6

the manual for the software specifies that Dints would work, and they do, because i can read in data from a transmitter and valve. i'm just not sure if it is working the way it is supposed to, since the data doesnt clear from the i/o after each page. and also i can't tell is the diagnostics are working.

 

[controlsdude]

As a known programming issue, buffer your inputs on a contrologix processor. Inputs are never stable over a scan on a contrologix processor unless you buffer the Local data input.

I used SST profibus scanner modules a few years ago with no success. Worked ok in house but when I had it out in the field became unstable. I know the SST eng stated to not copy their standard code but retype it, he said not me. Try to be careful about your setup on the scanner card when viewing the diagnostics on the front of the scanner card. I believe that was a scan issue internal to the scanner card.

Be careful about your swapping bytes and your nibbles on the scanner config. This will throw off your analog values if this is the case. The best way to verify this problem is by a know digital drop and setting a bit on that drop and seeing if it is that bit.

If I had the choice I would use Prolinx's profibus scanner. I was not impressed with SST help, maybe I was just too stupid.

I know this is late but oh well. Good luck and the devil is in the details.