SLC500 / RIO trouble

[Mr-Bi11]

Attempting to configure the following System.

Rack 1 - 10 Slot
SLC 5/04 [C]
SN Scanner
4 Channel Analog in
4 Channel Analog in
115VAC input (16)
115VAC output (16)
Empty
Empty
Empty
Empty

Rack 2 - 10 slot
RIO module
115VAC in
115VAC in
4 channel Analog in
4 channel analog in
Empty
Empty
Empty
Empty
Empty

Rack 3 - 7 slot plus 7 slot expansion
RIO module
2 in / 2 out analog module
4 channel analog in
DC out (16 channel sinking)
Empty
Empty
Empty
******
115VAC in (16)
115VAC out (16)
115VAC in (16)
115VAC out (16)
Empty
Empty
Empty

My question is what configuration do I need to get the block transfer working?

Switch settings on RIO's Config of SN Module and Ladder logic to read and write data.

Thank you, this is driving me nuts, I've been using AB PLC since before the slick500's came out but never used remote I/O.

Thank you.

 

[JaxGTO]

The SN module assigns remote IO like the PLC5 did. It only has Rack 0 thru Rack 3. Each rack is 8 slots of IO cards. Each rack can be broken down into groups of 2 slots. The rack sizes are 1/4 (2 slots) 1/2 (4 slots) 3/4 (6 slots) and Full (8 slots). You define these racks in the IO Configuration/ Edit G file.

Your discrete modules are straight forward. Each slot is the 16 bits for that module. Analog modules require a Block Transfer Read and Write. THE BTR/BTW use the M file for controlling the block transfer. It's best to read the SN manual on how to set those up. The M1:1.100-3100 are used for BTR and M0:1.100-3100 are for BTW. In Mx the x is 0 for output (BTW ) and 1 is for input (BTR). The :1 is for your SN in slot 1. Then you use the blocks is groups of 100 words using a UNIQUE block for each block transfer weather it's READ OR WRITE. I capitalize that because it's the most important thing. If you don't use a unique block for each instructions you will some very strange problems. So if you use M0:1.100 in a BTW and then try to use M1:1.100 in a BTR, they are trying to use the same buffer space and you will strange errors.

Your rack 2 would be a Full rack in the SN module. You have to burn that last slot because it's an odd number of slots. Keep in mind the ASB does not count in the counting of IO slots.

Your rack 3 would be 1 full rack and then a 3/4 rack. It must be continuous in the rack assignments. So if the first is Rack 1 (7 slot) then the second (7 slot) has to be Rack 2. Again burning the last slot because it's another odd number of slots.

 

[Mr-Bi11]

Thank you, What would I need the switch settings for each RIO need to be?

This can't be as hard as I'm making it.

 

[JaxGTO]

The SN just has selection for baud rate. This is usually set to 56.7K baud (a maximum of 10,000 feet of cable).

The ASB on the other hand has 3 switches. The basics most use are:
Rack, and Group. This must match what you set in the SN cards G file.
Like Rack 0 Group 0, or Rack 1 Group 4.

The baud rate must match the SN card.

Primary/Complementary. Your setup would be Primary.

Image size. If you use 1 slot addressing then image size is the total number of slots to scan (rounded up to the nearest 2)

1/2 Slot, 1 slot and 2 slot addressing. Save yourself a lot of head aches and only use 1 slot. This makes each slot 1 group in the IO.

Hold last state. I always turn this off. If this is turned on then if the PLC faults or goes to program mode, then the outputs remain in their last state, not usually a good idea.

Processor Restart Lockout. Leave this on or you would need to put a reset button to actually reset the rack.

Link Response Time. I leave this in the default position of On.

Last Chassis. I usually leave this in the default position of ON for Not the last rack. That way if you add another (higher addressed) rack later, you wont have to go back to this rack and turn it back on. This is usually only used if you need very high speed response from your remote IO.

Specialty I/O Mode. Because you are using analog modules you will want to set this Off to enable block transfers.

I/O Module Keying. Use the default.

As far as block transfers to your analog modules. Look at the individual manuals for those modules. If it's in the SLC rack and has 4 input words and 2 output words, then the BTR (input) would be a length of 4 and the BTW (output) would be a length of 2.

 

[Mr-Bi11]

Thank you for taking the time to go over this in detail instead of just telling me the positions, I guess my biggest hurtle was the terminology (group v. slots logical v. physical rack etc).

I think I have a much better understand from your post than reading several manuals.

Is there any issue with the empty slots in the sequence (rack3) or will the scanner just return 0000 or FFFF for them?

also do I need to do a block transfer for each slot or can I just return the entire rack withone read (if bit 0-15: first discrete IO, 16-31: second IO, 32-160 four analog inputs etc)?

I may head back to the office and work on this tonight now, you've been quite helpful.

 

[Ken Roach]

You only need to perform Block Transfers in logic for the Analog modules.

All the discrete stuff is handled automatically and put into the Slot 1 I/O image. Empty slots will return zeroes.

Try entering a BTW or BTR instruction in logic to see if your SLC firmware supports those instructions; if it's an older SLC-500 or very old RSLogix 500 software, you won't have the convenience of the BTW and BTR instructions and instead will have to do them old-school with subroutines to move blocks of data into and out of the M-file buffers.

 

[JaxGTO]

if you stick with 1 slot addressing then you just use Rack/Group and slot is always 0. And that slot has nothing to do with the actual rack slot.

No the empty slots will just return zeros for that position.

No you will need block transfer for all analog modules. The IO table for those modules is unused. For example if your analog module was at RIO Rack 0 group 2 of the SN in slot 1 then the input word I:1.3 and the output word O:1.3 would be unused.

No problem I have been using RIO since the 1771-PLC days back in 1983. So I know how confusing it can be.

 

[Mr-Bi11]

Yes Series C processor will do the block transfers.
Wouldn't rack #2 (logical #1) be 1+1/2 rack (12 slots) instead of 1+3/4?

I'm getting an 'adapter decide reset' on both RIO's now...