Prosoft MVI69-MCM with Compact Logix

Dear All,

Am are using Prosoft Inrax MVI69-MCM with Allen Bradley Compact Logix processor to Read/Write the data from Modbus Slave device.

Here we need to Enable/disable the write command from ladder logic. Is this possible with device? Kindly Advice

Regards
Joseph Francis

Yes it is possible that is what the MVI69MCM was made for.
I just completed a project using the MVI69MCM and Compactlogix if you have any questions feel free to ask.

Dear Catania,

Thanx for your reply.Kindly send me more details of enabling & disabling commands of MVI69-MCM from ladder logic.

Regards
Joseph

If you can be more specific it would be easier to help you.
What is the register number you are writing to (your slave register map). Are you able to read any data at this time? Are you using the command error pointer of the mvi69mcm?

There is no direct way that I know of to programmatically Enable or Disable a specific Command in the MVI69-MCM Master Command Table, in order to place it into the polling list or remove it from the polling list.

But there are several ways to trigger a Modbus Master command on an event basis.

The easiest of these is to set the Enable parameter for that Command to a value of 2, indicating a "Conditional" write. The module will then only send a Write when the value of the database location associated with that Command changes.

There are multiple other methods, including the Slave Enable/Disable control block, which enables or disables ALL messages to a specific slave.

There's also Special Function blocks, and Event Command blocks.

All of these are described in the MVI69-MCM User Manual.

Tell us more about your application: how many slave devices are you reading and writing to, how many Commands are configured for each, and do you want to send individual Writes, or actually place a Command into the polling list so that it is continuously polled until you remove it from the polling list.

Example:you have a register 40128 Bit 4 of 40128 is a command. Bit 4 is = to 16 in dec. Create a tag in your ladder logic and and move 16 to the tag, then use the cps or cop instruction Source=Tag you created
Dest= mcmwritedata 301 or 302 etc depends on how you have it set up in your prosoft builder.Lenghth=1. That is one way of writing you can come up with other ways in the ladder logic if you please.

Dear All,
Thank you for your replies .In my application i have Five slave devices (Compressors-Mycom).Here i want to select or change operation mode of compressor from plc as well as from compressor .But if i enable the write command for that register (MCM) , then it is not possible to change it localy from compressor.

Also in this application, compressor regiters are not consecutive,So the number of read commands are more,because of this I am facing delay problem.So If i have control on command , then i can only read the data of running compressor.For more details am enclosing here with the command list of MCM module.

Regards
Joseph

Dear Ken,

I have go through the Mnaual of MVI69-MCM , but i could not found the details of command control.

Regards
Joseph

Look at the Event Command feature, starting on Page 125 of the MVI69-MCM User Manual.

You will remove the Commands that you want to selectively write to the compressors from the Command List, and instead insert them into the high-priority polling list using Event Command blocks.

To decide on whether to use Event Commands or Special Functions, the question is "do I need to write commands to one compressor at a time, or several all at once".

Are the compressor mode setting Commands the ones shown as Function Code 6 and labeled "Compressor - 01 Write -01" in your Command list ?

Catania said:

Yes it is possible that is what the MVI69MCM was made for.
I just completed a project using the MVI69MCM and Compactlogix if you have any questions feel free to ask.

Click to expand...

can you please send me rslogix5000 program of your project as i am starting a project and i am really very confused in its configuration and message instructions

Dear Joseph i am also starting a project similar to as you did,i have mycom compressor with cp4 and my mvi69mcm(as master) with compactlogixl43,i am trying for last 6 days but didnt got any solution,i cant even recieve any data in mcm internal memory.is it necessary to use a 120ohm resistor in my prosoft 9 pin connector..plz help me with configuring this module i have tried support from a lot of places but no fruitfull result was seen.

Dear catania can you plz send me the configuration file of your mvi69mcm and your rslogix5k acd file,is it necessary to use a 120ohm resistor in 9pin connector of prosoft module and is it also essential to use pin no. 5(common).