What Hardware do I exactly need

[chay]

Hello everyone,

I have a project where I'm supposed to make a machine, using the V570 (and program it with Visilogic 9.8.79 beta). This machine is required to detect the reference numbers of smth else through its RS232 port, run some tests and then print a label that the thing it tested is in a good shape ( that's just a global view about what I'm supposed to do ). Given that I only have the V570, I know that I/O ports must be added, though I'm clueless to what exactly ask for. I did some researches, and found that there are "snap-in" and "I/O expansion modules" that can be added, still I don't get the difference between them. So my questions are : 

- what are the Snap-In and I/O Expansion Module exactly? when and where do we use  each of them? 

- How do I chose what should I add to my V570 ?

- What hardware (other than the V570) should I exactly have for this project ?

thank you in advance

[Flex727]

The Snap-In I/O module snaps directly onto the back of the V570 PLC. It's a convenience. The I/O Expansion modules offer more flexibility and a greater number of I/O points but must be mounted on a DIN Rail. Otherwise there isn't much difference - the biggest difference being that the I/O expansion modules have lights for each digital I/O which can make troubleshooting a bit easier.

Your first task in identifying I/O modules is to list all your needed I/O points, both digital and analog, and any communication requirements.

[chay]

I see. Thank you so much.