CompactLogix to UDP device

Dayvieboy

Lifetime Supporting Member
Join Date
Jun 2013
Location
San Francisco Bay Area
Posts
132
I am looking for someone who can get our L36ERMS CompactLogix PLC to talk to a device that uses UDP
We only need to turn on and turn off the device. Basic function.
Any suggestions on who can do this work?

Dave
 
SD_Scott It is not a registered device...

It is a sputtering ION pump, Part of a Ultra High Vacuum system
for an Electron Beam Microscope system that we are designing.
 
BITS N BYTES

Thank you for the reply,
I had been looking @ that document as well as some others before posting.

Building from scratch and doing all of the needed debugging, I can probably muddle through,
but would take me much longer than somebody else that has done it before.

The Sockets manual mentions how to create needed messages ie. Open Socket, but not much on the needed code in front of the messages, other confusing things are it tells you to create a “Source element” UDT but no mention of radix or size.

I did get the Modbus TCP I/P sockets to work using sample code.
Sockets uses some memory but is cheaper, has a smaller foot print and creates a cleaner build.

Another bonus of working through this is now we do not need to buy expensive Modbus TCP I/P cards for every tool :D

I have not found a UDP sample code for Compact Logix yet.

Maybe I can take apart the Modbus sample and learn a bit.

It has to be 100% reliable and there may be a learning curve I am trying to avoid.
There is money in the project to pay for help.

Dave
 
BITS N BYTES

Thank you for the reply,
I had been looking @ that document as well as some others before posting.

Building from scratch and doing all of the needed debugging, I can probably muddle through,
but would take me much longer than somebody else that has done it before.

The Sockets manual mentions how to create needed messages ie. Open Socket, but not much on the needed code in front of the messages, other confusing things are it tells you to create a “Source element” UDT but no mention of radix or size.

I did get the Modbus TCP I/P sockets to work using sample code.
Sockets uses some memory but is cheaper, has a smaller foot print and creates a cleaner build.

Another bonus of working through this is now we do not need to buy expensive Modbus TCP I/P cards for every tool :D

I have not found a UDP sample code for Compact Logix yet.

Maybe I can take apart the Modbus sample and learn a bit.

It has to be 100% reliable and there may be a learning curve I am trying to avoid.
There is money in the project to pay for help.

Dave

I believe the third option form this search is what I ended up successfully using:

https://www.rockwellautomation.com/...essionID=7acd159b-b4e9-afeb-c841-5cc023c6093d

There should be an option in the way the message is structured to flag it as UDP/TCP/both iirc. It's been a little while since I went down this trek, and i no longer work at the facility where I needed to use it unfortunately.
 
Recently used this very helpful article and sample code as a basis to develop UDP communications from a CompactLogix 1769-L18ER-BB1B.
Even though this example is for a Kollmorgen drive, the principles involved can be used/modified to communicate to any device via UDP.

Just be aware that UDP is a blind communications vs. TCP.
In general there is NO automatic response or confirmation that data has been received when WRITING a UDP message.
Ideally the receiving device should have a READ parameter to confirm its state.
So with your application you would WRITE either ON or OFF followed by a READ to confirm the state has changed.


https://www.kollmorgen.com/en-us/de...n-akd-pdmm-and-rockwell-compact-logix-l18erm/
 
Last edited:
If you only need to turn it on and off, why don't you just use discrete I/O?

SD_Scott
If it had discrete I/O we go that route.
Unfortunately it only has UDP ethernet control at this point.
 
Recently used this very helpful article and sample code as a basis to develop UDP communications from a CompactLogix 1769-L18ER-BB1B.
Even though this example is for a Kollmorgen drive, the principles involved can be used/modified to communicate to any device via UDP.

Just be aware that UDP is a blind communications vs. TCP.
In general there is NO automatic response or confirmation that data has been received when WRITING a UDP message.
Ideally the receiving device should have a READ parameter to confirm its state.
So with your application you would WRITE either ON or OFF followed by a READ to confirm the state has changed.

January 13th, 2019 02:00 PM


BITS N BYTES
Thanks again for the input, Sorry for the delayed reply..

I started to play with the Ethernet UPD a little bit but did not finish.

I decided to push back on the supplier of the Sputtering Ion Controller.
by asking them to upgrade their firmware to support Modbus TCP I/P.

The company I am contracting with buys enough hardware from them that said they may be able to have it ready in a few weeks.

Good news..
In hindsight, I should have asked for Ethernet I/P with an Add On Profile :)

Thanks again for the help.

Dave
 
Glad your project is moving forward.
YES, Ethernet/IP vs. ModBus TCP would probably be your best approach.
After developing/testing UDP communications using the example as a basis for development we persuaded customer to change comms. to TCP on their device.

Worked like a champ,easy to implement and fast.
Adding yet another protocol [ModBus TCP in your case] just seems like overkill.
Good Luck and your feedback is much appreciated.
 

Similar Topics

800 byte UDP packets are too large to be handled by the compact logix 5370 controllers. The processor sockets buffer is in the region of...
Replies
22
Views
5,224
We are trying to poll data coming from a PLC for remote monitoring we have the IP address of the PLC and the default port number and the path is...
Replies
25
Views
418
Hi everyone, this is my first time trying to setup encoder counts and track the traveled distance and speed i am using L27ERM QBFC1B processor...
Replies
12
Views
331
I have a device that is currently connected to a UR 10 robot through a UR Cap and I would like to connect the device to an Allen Bradley...
Replies
3
Views
316
I have a device that is currently connected to a UR 10 robot through a UR Cap and I would like to connect the device to an Allen Bradley...
Replies
0
Views
102
Back
Top Bottom