advice on selection plc system

i have in my possesion some data sheets, i need to select a system that shall have 30 inputs to work wth 24V sensors and 30 outputs operating at 24V DC. could you give me a clue to what i should be looking at selecting?

I am thinking of;
No of o/p=32 (2sets of 16)
12/24 dc source
10-31.2 V dc operating voltage
i am going to use Allen Bradley MicroLogix
also what should i be looking for in a controller?
120/240v ac?
Should i be selecting an expansion unit too? banghead
Currently Discussing this with the C&I Engineers at work but i would like to hear what you all think too as the advice, and help i have recieved from this site has been very helpfull.
beerchug

I am reading into your post that you are set on an AB controller, probably because thats the standard at your company.
By all means stick to what is dominant at your place. There shall be very compelling reasons for straying outside "the norm".

Which AB controller then ?
Your Micrologix can be OK, but you should consider many things, its not allways the smallest and cheapest solution that is the best one.

- Does your company use other AB types ?
- Is there a chance that the application shall be modified at a later time (does the controller have enough memory to handle the potential application)?
- Do you need online editing (not in any ML, from SLC5/03 and up) ?
- Do you need networking ?
- Do you want to go with new generation of AB controllers, or stay with the old (a compactlogix could be the ticket, but from the postings of others I would say that the new generation is not 100 % mature yet).

thats what I can think of off the top of my head.