Rockwell HW Config - Remove a IO Card from Point IO

[jthyge]

Hi

I have removed at IO card from a 1734-AENTR Point IO, from a slot in the middle, and moved the remaining cards together.

Now the Point IO is Faulted. The internal state is Unconnected.

So the Slot Chassi looks like this, with one slot missing: [4]
[0]
[1]
[2]
[3]
[5]
[6]
[7]
[8]

How can I solve this?

 

[ASF]

You have two options:

You can shuffle all your slot numbers from 5-8 down one space to 4-7, and adjust the chassis size from 9 to 8. You may need to re-map any I/O or aliases using those addresses; I *think* they will update automatically, but you would need to check.

Or, you can put the terminal base back into the slot 4 position, and install a 1734-ARM (address reserve module) in its place. Or any other module for that matter. Configure it in the I/O tree as a generic module and inhibit it to prevent the PLC from trying to connect to it.

Generally I'd go for option 2, because then you don't have to make a lot of drawing updates to adjust modules 5-8 (or what are now modules 4-7).

Why did you take the module out in the first place?

 

[joseph_e2]

I like ASF's option 2 as well.

One of my earlier "from scratch" projects involved replacing an old PLC (5, I think, or maybe SLC150) with a CompactLogix and I put the resolver module on the end close to the 480V feed (2 rookie mistakes in one...). It kept dropping connection. I ended up having to move the resolver module to the other end of the chassis and shifting all of the other addresses by one slot. I don't remember the program itself being much of an issue to change, but the drawings were a pain to change. There weren't a lot if IO, so it may just have been easy enough to modify that the memory didn't stick. Ideally, I should have rearranged the cabinet, but space and time were both very limited and the original PLC was in the top left next to the disconnect switch. The relay output module did fine being next to the 480V, though.

 

[jthyge]

Thanks for your reply.

We inserted a spare card in slot 7, then the the Point IO was happy.
Did not have to do any HW config changes in the PLC. Of course we need to do that if we will use the card in slot 7.