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Hi gents.... first of all sorry for my english writing , I'm Italian ...
I'm a newbe on EMC (but i'm watching this forum during the last two month) and I wish to use Classic Ladder and Modbus TCP/IP.
Maybe I'm wrong but after the reading of the integrator manual I understood that the Modbus Master TCP/IP is not tested yet.
So please can anybody give me information about that ?
I would like to extend the I/O of the system for test it in an industrial enviroment (so 24vdc I/O).
Thanks a lot for any advice.

bigalex

Modbus TCP/IP has not been tested in EMC. It has been tested in the parent classicladder by the author Marc.
I toyed with trying to get it to work but have little idea how TCP works.
I could not get the master and slave to connect - though the slave program I was using may have been the trouble as well.
You could try downloading the original classicladder, get modbus to work then apply that knowledge to EMC classicladder.
If I can get specific directions about how to setup a TCP connection. I would try again.

Hello cmorley thanks for the reply..
I'm not familiar with Linux/Ubuntu.
This is my first experience with that so I think I will have problems installing/managing software packages under Linux/Ubuntu.
I have already hardware devices available to test the Modbus TCP/IP (remote I/O or PLC as well) and maybe a soft modbus slave simulator.
The configuration I'm thinking about is that EMC is the master and the external Modbus nodes are slaves.
I have already used Modbus TCP/IP in PLC's applications and usually you have to declare (inside the master config) for the slaves configuration
the IP address and the slave number .
What I've seen on the integrator manual is not so clear for me (sorry).
I have already activated the Classic Ladder inside EMC and is working (just test some logic combination), unluckily the instruction set is poor but this is
another story.
If you can give me more information on how to download and install the original Classic Ladder I will try to do something more on Modbus TCP/IP.
Do you think that Marc can be collaborative on this ?
Thanks ...... I wait for news.

bigalex

Hi to everybody ....
Today I tried a test for ClassicLadder and Modbus TCP/IP with a small I/O device (Zelio Logic by Schneider Electric) and it's working fine.
This device can exchange up to 4 words as Input and 4 words as Output and can also manage logic program itself.
The communication is over Ethernet (TCP/IP) so the speed is nice at 100MB.
With this configuration will be possible smoothly to extend the I/O of the system.
I read that many users need I/Os on their system and sometime they need to use more than a parallel port into the PC.
In this case using the ClassicLadder and the Modbus TCP/IP is possible to extend the I/Os also in an industrial enviroment where usually the
voltage for the sensors (limit switches and so on) and for the actuators (solenoids, relays and so on) is 24vdc or higher and the interfaces must be optocoupled.

bigalex

Did you run Classicladder by itself or inside of EMC?

I would be interested in any info on how it works with EMC to add to the EMC Integrators Manual.

Thanks
John

Hello John nice to read you.
I'm using ClassicLadder running with EMC2 .
Today I'm running the test again , the Modbus TCP/IP communication is working fine till now (I started 6 hours ago) and no problems at all.
I made a test performing estop request from the modbus slave passing trough ClassingLadder and Hal (Halui was activated) and the test is positive.
I used the Modbus functions 03 (Read holding registers),06 and 16 (Write holding registers) .
I do not know what is the latency on the communication but seems to be fast anyway and sure it is better than the serial line.
I will try to make a remote pendant to command the axis movement and auxiliary functions using a Modbus TCP/IP node for the I/Os and maybe for the handwheel (using a fast encoder counter 24vdc on the modbus node).
As soon as possible I will give more informations about but just in case ypu need a specific information please do not esitate to make questions.
As I told in this thread I'm a newbe on Linux and EMC2 so I hope to increase my personal skills on that and expanding the knowledge.
John the manual that you made are really precious

bigalex