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BourneToRide

SLC multiple racks into 1756 (DH)RIO

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I am converting a multple rack SLC project to CLX and as a fist step I have to keep the SLC racks while converting to CLX processor.

There is an existing CLX rack with 1756-DHRIO card talking to other SLC over DH+ and i thought it would be fairly simple to connect all the 8 SLC racks via the RIO channel.

Except the first rack has 2 extensions with zero spare slots, where i was considering 3 x 1747-ASB, now can I use single ASB in slot 0 where SLC resided to connect to all 3?

Same with another rack already on RIO, the first rack has ASB installed but the extension has no spare slots.

The documentation I have suggests I can only address 8x 16 bit cards on each rack, or have i got that wrong, most of my cards are IB16 or OB16, just the very first rack has analogs.

Is the 1756-RIO card any better at addressing 25x 16 way cards as 1 rack

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Since you have to replace the CPU anyway, consider the 1747-AENTR. That would turn the SLC chassis into an EtherNet/IP node that the CLX can reach pretty easily.

I've never used it in the real world, but when you put the 1747-AENTR into the ControlLogix project, you can set the chassis size up to 31, which is what the extended SLC chassis maxes out at. You can then populate the SLC chassis with its modules. Not sure how well that would work out, but see if you can configure it offline. You may need to search the "secondary market" for modules, though, especially for the -ASB which was discontinued back in 2013. The -AENTR is still made, but it's "Active Mature" and list price is VERY high.

What SLC PLCs are in the racks? If they're 5/05s, you could turn them into IO processors of sorts and have the CLX use MSG instructions to read/write IO with the code running in the CLX. That's far less ideal a solution, but could work without having to buy expensive hardware that you're going to replace anyway. I did a migration from PLC-5 to ControlLogix and we ended up just replacing all the IO in one fell swoop since the changes to the system were so extensive already. I'd seriously consider that option as well if it's at all possible. It may be that you can get your hands on the COMMS modules easier than the new IO modules, especially analog ones. Those things are really hard to get over here.

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There's only 1x 5/04 processor in this project, all other existing remote racks have ASB cards, 

I had looked at the AENTR but £3k each x 5 for a couple of months use is way too much, I managed to pickup a 1747-ASB card on ebay for £100 and it will be useful in the testing phase and kept for further upgrade testing.

Changing everything in 1 phase is not an option here, just too much to do in the time available, so we are left with a hybrid interim..... whatever that looks like

AIB is little help, only showing AENTR, not ASB. Now beginning to realise why that is

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You'll want to get familiar with the Manual - https://rockwellautomation.custhelp.com/ci/okcsFile/get/16777223/236567b785b18-89b4-468b-99d5-beafbc99e85b/714906352/PDF/714906352#__highlight

Starting at Chapter 9 is RIO Setup Information.

Chappter 10 shows the intracies of programming.

And don't forget you're limited to on the number of Block Transfers.

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Thanks Bob

Found a KB article (id/19047) which suggests setting virtual ASB in the IO tree, due to Logix500 only assigning 8 x 16 bit words per ASB

So for 25 IB16 cards it looks like I will need 3 x virtual ASB setup with full rack, 8 words/cards and 1x ASB as 1/4 rack

The physical ASB will retain its DIP switch settings as it is currently working,

for first rack just need to swap out the 5/04 for ASB set for 24 IO cards ( mix of IB16, OB16 & NI4)  assign 3x virtual ASB, I'm sure its not going to be that simple but at least its progress

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Haven't messed with CLGX and ASB in years, but as I recall there are some Thermocouple and/or Analog cards that pose a headache.

So I hope you're all DI /DO stuff.

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