Modbus TCP to InTouch Problem.

[Mark_]

Hey there Folks. I could use some advice.
I need to read a handful of data points from a Modbus TCP server into InTouch v11.1, but without using DASMBTCP. Any 'simple' alternatives?

The short version is that I can't get DASMBTCP to work, after days of trying. Even my Wonderware tech support lead guy couldn't get it to work, and he had to escalate the issue to a WW top dog ... then silence from them for weeks.
I can read the data fine using ModScan and ModbusPoll from the same PC.

I'm green on OPC, is that an easy enough option?
I'd rather avoid adding hardware... remote site.
Is it a faux-pas to try and hire a pro via this forum? Payment in high-fives and/or dollars.

 

[Mark_]

... PLC is ControlLogix, but has an ENBT ethernet card, therefore can't use AB's fancy sample code modbus read AOI. Needs to be EN2T for that.

 

[defcon.klaxon]

Can you tell us more about what DASMBTCP was doing/not doing? I've used it a lot and it can be finicky to get just right.

What exactly, hardware wise, is the modbus server you're trying to communicate with?

 

[Mark_]

DASMBTCP 3.0 SP1
Reading from an Eaton PXM-4000 Power Xpert power meter.

- WW data quality status values have been either 0, 4 or 27 through various attempts.
- I have minimal modbus experience but I've tried every syntax permutation I can think of for WW item name. From the PXM register table; one register in question is 4671. And I'm looking to read only.
- with tech support we tried tests with the wwclient.exe utility and got same results. So it's not an error in WW tag database config, it seems.
- All DAS config settings are per the DASMBTCP manual.

A real head scratcher for me (and I don't have much hair left to loose).

 

[lostcontrol]

Hey there Folks. I could use some advice.
I can read the data fine using ModScan and ModbusPoll from the same PC.

Payment in high-fives and/or dollars.

Can you show the ModScan config.?
Something doesn’t look right with yr registers & am wondering if you might need to use the ModbusBridge instead of ModbusPLC.

 

[Mark_]

Modscan screenshot.

I had tried ModbusBridge initially, though only briefly. I can revisit.
Ya, I'm making educated guesses with Item Name syntax. Even after reading manual it's unclear to me.

 

[muusic_man]

You probably tried this but have you tried to set "Swap String Bytes" to on in the DASMBTCP setup in Intouch. If register 2002 in the meter is not 0 then the string data could be reversed.

 

[KirkC]

You have chosen 6 digit addressing.

The first register you read with Modscan would have item name 404660.

I recommend you select "Advise all items".

 

[ynpmoose]

Since the Unit ID is 1, you must use the ModbusBridge in DASMBTCP, then use the ModbusPLCRS object and set the ID to 1. If you use the regular ModbusPLC root object, the ID is assumed to be 255.

Also, KirkC's addressing suggestion is 100% correct. Or you can change DASMBTCP to use 5 digit addressing and leave your addresses without the 0 filler.

 

[Mark_]

ynpmoose, YOU NAILED IT! IT'S WORKING!! High Five!!

I was just about to give up as you posted. Literally.
I had tried ModbusBridge with the WW tech support guy but not PLCRS it seems.

Huge thanks to all of you. You are all now on my Christmas card list.