SLC 504 Processor Firmware Versions

Hi All,
I have a customer that is using a SLC 504 processor. The Catalog Number based on the RSL program I have is a 1747-L532C. The OS is a 1747-OS401 Series C FRN 3-8.

They have a spare processor that they asked me to install their program to. They would like to be able to just swap it out if there is a Processor failure. The Catalog Number is 1747-L542 Ser. B Rev. 3. The OS is 1747-OS401 Ser B FRN 9.

My question is: Since this spare is a older rev does anyone see any issues with me installing the program from the working unit into the spare? I know it can be upgraded but is that necessary? Any ideas on this would be appreciated!!

Thanks

The newer OS 401 Series C operating system contains some functionality (like DF1 Radiomodem, or DEM DeviceNet explicit messaging) that the old OS doesn't support.

If the program uses features that are only found in the Series C operating system for the SLC-5/0x controllers, then you can't use that older controller.

It should be straightforward to find out: Change the Controller definition in RSLogix 500 to the older OS and revision, and see if the program will compile.

The chassis, power supplies, and I/O modules will definitely be compatible; don't worry about those.

Thanks Ken,
I did just that and found a issue. The program has some BTW and BTR commands to read some RIO Analog Modules. If I did a OS upgrade would that take care of the problem?

If not it may not be that big of a problem as they don't use those modules at all. The original designer had the Analogs for tank level but they ended up using a different level system. So I just remove that part of the program and everything worked fine.

I would like to make everything the same so if I can just do a upgrade then I might go that way.

does this system communicate with other PLCs over a network connection? ... if it does, you need to double-check your part numbers, etc. ...

the 1747-L532 that you mentioned is supposed to be an SLC-5/03 processor – which usually communicates over a DH-485 network ...

the 1747-L542 that you mentioned is supposed to be an SLC-5/04 processor – which usually communicates over a DH+ network ...

this might just be a typographical error – but make sure that you're not going to run into any sudden surprises in the communications department ...

of course if this is a "stand alone" system with no network communications, then this is probably a non-issue ...

It was just a typo. Both Units are 1747-L542 Processors. Sorry for that.

The Block Transfer instructions (BTR and BTW) are some of the improvements that were in OS401 Series C.

You could delete the parts of the program that deal with those block transfers, or you could re-write the block transfer function in the "old style" using logic that copies configuration and data blocks into and out of the 1747-SN module.

An SLC-5/04 with any version of OS401 should be upgradeable to the newest OS401 Series C FRN 11 using a firmware upgrade plug kit. It's a chargeable item, and you'll want to check with RA Technical Support to verify that the existing controller will accept the upgrade (I haven't done one of those specific upgrades).