One HMI To Multiple PLC's Best Practice

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I am designing the control for a system of processing tanks, each with it's own PLC and controlled by one PC running AdvancedHMI. This is the first system like this I am designing that will consist of a few identical cells and one HMI. My first thought is to have all the PLC's use the same exact program, just have it's own IP address - something like for tank #1, ...0.2 for tank #2, etc. - but each PLC using the same exact tags and I/O. 

I am thinking this would be easier later when adding more tanks (now there is one tank being tested, but depending on demand there will be 4 to 8 tanks eventually) 

Should I go with this idea, or have each PLC use different tags so as not to be confusing? I would like to know of any problems or ideas others may have come across doing this.

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I think it would be easier to deal with if they all had the same tags. The only tricky thing would be making sure it's easy to connect to the correct PLC depending on which tank you're trying to troubleshoot. If I'm trying to connect to tank 3 and accidentally connect to PLC 5, I could end up chasing rabbits for a while until I realized it. What PLC platform are you using? If you're using Allen-Bradley, you have to "name" the processor. Giving each PLC a unique name will make sure you're connected to the right one. Other platforms don't do things the same way.

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You should start using naming conversions on your Tags.
for instance a tank level could look something like. Tank01Level.
From an IEC point of view you would actually make a DUT\DTU for your tank. consisting of certain parts

This way the tags would look like:

Tank01.level / Tankxx.level

Tank01.Temp / Tankxx.Temp

Either way use individual tags so when you link or import  your programmed labels to your HMI/SCADA they are not the same.

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