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Unistream application with 3rd party field interface outputs

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I have an application that I have built already in Unistream that I need to replicate but also to expand.  

The system primarily controls valves uisng discrete off/on outputs via transistor outputs through isolation relays.    There are some other functions but the lions share of the outputs are valves.   

The smaller version only has 10 valves but there is a larger system with 46 valves; so as you can imagine there's allot of hard wired relays.  

I need to condense the panel footprint as well as reduce labor to build; so looking to use Ethernet I/P addressable solenoid valve manifolds to eliminate relays in the panel and the labor to wire same.   Have reviewed the information from my SOV mfg's details on their Comminication module interface; and they support  Ethernet TCP/IP. 

I've never worked with ethernet connected field devices that are 3rd party however so this is a bit murky just yet.  

Have looked at the COM: EtherNetI/P functions blocks from the drop down menu off the Ladder Toolbox, reading some of the help files; but as yet I havent found perhaps a sample program showing how they get implemented; perhaps I'm overlooking.  

thanks for your pointers  !   

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If the manufacturer offers EthernetIP, then you don´t need those ladder functions, just a few steps to configure the PLC as Ethernet/IP scanner importing the EDS of the device.  It will create the structures and IO tags required to comunicate to/from the valve controller.

Take a look to the examples that can be downloaded from https://downloads.unitronicsplc.com/Sites/plc/Unilogic/UniLogic_Examples.zip




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  • 2 weeks later...

Main question you have to think about is: how fast do you need these discrete I/O to be?

If you can tolerate 50-100 milisecond latency, then taking a Modbus TCP or Modbus RTU I/O gateways might be a less expensive alternative to Ethernet/IP.

UniStream can be easily configured to send outputs and read inputs from a Modbus field I/O station. Setting up fieldbus in Unistream is almost trivial, no coding is necessary. Just define tags, set polling time or trigger bits, and it works auto-magically.

Now, if your I/Os must be fast (response time in 5-10 milisecond range) or real-time, then you should look for CANopen fieldbus I/O.

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