The Micrologix PLC has its own timer functions etc inbuilt just look at the manual for it, check out the programming software, as for lights and switches, look at what else is used on other panels around the site and use the same type, this makes the storesman's life easier. all you need to know is what do you want it to do, what voltage are you going to use to do it with, I/O refers to how many imputs / outputs the unit has, Back to basics now Lights to OutPuts, Switches to Imputs. check the switching capacity of the out-puts and don't exceede this, be aware of inductive loads if in doubt use the output to switch a seperate relay/contactor and rate this to the load required. I'm sorry if this sounds condescending but i guess you have very little experience with electrics and controls. what are you trying to do? more details are required before i can help any more?
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