What are these I/O's 3

[spongebob17]

Hello,

Just graduated as an electrical engineer.

Anyway, I am evaluating I/O's for a CIP System. On one of their CSS 425gpm pumps (coming from a Water Reclaim Tank), it said 2in/2out, with Analog 1in/1out. What would these I/O's be? The analog I/O might be for a VFD and the other 2in/2out I'm guessing is running/fault at the input side and reset/? at the output. I'm not sure...can anyone explain why there are 2in/2out?

Thanks!

 

[CliveRoberts]

I/O means input/output. A digital input (DI) only has a high value or zero. Its either on or off as an input to your PLC. Eg, start signal through the PLC. (Either 24Vdc or 0Vdc - On or off).
Digital outptut however (DO) is an output signal from the PLC or controller. It gives out 24Vdc or nothing to switch on a siren or something.
Analog Input (AI) is a varying signal to the PLC such as a potentiometer, where you vary the speed of a motor through a PLC. It tells the PLC that Im more or less.
An Analog Output (AO) is varied signal from the PLC, normally from a PID block on your code that varies the actual speed of a motor through a Variable Speed Drive (VSD) in response to the Analog Input action.

I hope it helps a bit as I was explaining it in a very broad context.