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plc selection

plc selection

plc selection

(OP)
Gents

Wondering if any one can help out here, we have a new little project that, because of the size of the existing case, needs a pcb based plc.

The I/O count is tiny, max of 6 dig in, 4 out . It has to look at a sensor and display the number over a range 0-1000 so needs 1 analogue in and either a little (<2in) HMI or an analogue output I can use to drive a digital meter. 10 bit a/d is the minimum to give is the 0-1000 range, more would be better.

Can anyone suggest a suitable unit please?
 

RE: plc selection

One off? Or hundreds? Maximum dimensions? Power available?

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: plc selection

(OP)
Itsmoked...... Thanks for that, those smart relays always seem to run out of programming space whenever  I've used them in the past, also I can see an easy way of driving the display we need.

Gunnar......Thanks also, size is flexible up to say 200 x 200 but height is max of 70mm, volume is going to be low, 10-20 pa, power can be mains or (preferably)  12/24V  
 

RE: plc selection

(OP)
Edit.....

also I can see an easy way = also I can't see an easy way  

RE: plc selection

I would talk to someone making custom boards. Keith is one possible source, but there are hundreds doing the same thing. Depends where in the World you are.

Do you really need the quick programmability a PLC offers? Or can you live with a more or less rigid program where all you can do is setting modes and parameters?

A custom board with a PIC with 12 bit A/D and PWM analogue outputs would do the job nicely.

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: plc selection

I second the smart relay option. This application seems simple enough to be tackled by the limited memory of these units. A lot of them are expandable, have communications and have integraded displays and interface buttons.
There are other small PLC options such as Micrologix, automation direct Click. Pretty much every PLC manufacturer produces a small PLC with onboard IO.

RE: plc selection

And at 200x200x70, there are plenty of small units that can fit in that space.

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