quick Clx question

I have 9 1769 IO(IB and OB16) cards. What Compactlogix model supports up to 10 or 16 IO cards in its local bank? I read L43 can only handle 16 cards but only 8 cards in its local bank and L45 can handle 30 cards but is it still up to 8 cards in local bank? cant use 36ERM since it's also limited to 8 local IO cards. I'm avoiding expansion power supplies.

Thanks

The problem you have is not which CPU supports how many cards, but your power supply distance rating. Your CPU has a distance rating of 4, which means it can be 4 modules away from the power supply. The highest distance rating of any 1769 I/O card (that I've ever seen) is 8 (some cards are even lower). Your CPU has to go on the left hand end, so you get CPU, 3 I/O cards, then you have to have the power supply. Then you can only stick a maximum of 8 cards to the right of the power supply before they're outside their allowable distance range. So CPU limit aside, you can only get 11 cards in a local 1769 I/O rack with one power supply.

Your best bet would be to switch the 16 channel cards for 32 channel cards and halve your card count. But then, if you've already got the cards, it'll be cheaper to just buy another power supply. As long as you have the space for two racks

I think there's no power supply that supports more than 8 I guess so thats the only way to go. thanks ASF.

Yeah, it's not the power supply though so much as the cards. Some cards have to be even closer - from memory the 1769-OB32 has a rating of 6, and there's an ASCII module with an even lower one. On your second rack though you can put 8 cards either side of the power supply. So if for whatever reason you just want one i/o rack, just have a PLC and a P/S on it's own, and then you can have all your I/O on one rack below. You still need two power supplies though