PLC 5 and Modbus RTU

Steve Cav

Member
Join Date
Aug 2006
Location
Clitheroe
Posts
71
Currently we are communicating to Vishay Nobel weighscales (TAD 1) serially (Modbus ASCII) via a DB module.

However, these are now obsolete and it's replacement is the TAD 3 which cannot be communicated with using Modbus ASCII, only Modbus RTU.

Although there is a firmware download provided by Vishay Nobel which will allow limited functionality of Modbus ASCII (and would suffice for our needs) we have several units (most connected via Modbus ASCII and 1 connected by 4-20mA analogue input) and we would rather re-write the communications code to handle Modbus RTU, than start flashing the firmware depending on which weighscale fails.

A quick google has found that Prosoft provide a card to communicate with Modbus RTU but has anyone successfully connected a Modbus RTU device to PLC-5 and if so, how?

I'd like to avoid using a RB module if possible.

Steve
 
Steve,

Along with the Prosoft card, you could also consider the Red Lion DataStation Plus product to do this. Testing should be done with a SX model and then you may find that the LE version will cover your comms protocol changes.

Thanks,
Joe_WaZoo
 
5/40 Modbus module

Prosofts MCM-3100 is the MODBUS module that can be installed in the 5/40, But you have to write a good logical program using BTR and BTW instructions, this module can not be programmed using MSG instructions, you need to be good at programming.
 

Similar Topics

Hey everyone, I am seeking assistance on finding and solving potential cause of a Modbus RTU issue, from a Micro820 PLC. We are unable to...
Replies
6
Views
1,221
Hello Guys, I have a packaging machine in the company that I work for that have 8 Omron VFDs (3G3MV ) that are controlled via Modbus with CJ1M...
Replies
1
Views
585
Hello everyone! Posting from Argentina as I don't know what else to do. For a bit of context, I am using an Allen-Bradley Micro850 PLC and five...
Replies
16
Views
10,331
Hi all, Has anyone dealt with Modbus RTU communication using SE`s Machine Expert? I have got the modbus tcp working, but not used the serial...
Replies
1
Views
1,189
Hello Experts, Once again I am here as could not find information. I am reading and writing to Modbus RTU device through Anybus communicator...
Replies
4
Views
2,636
Back
Top Bottom