PLC5 rack addressing

usajrz1

Member
Join Date
Dec 2019
Location
Indiana
Posts
6
Ok so to start - im brand spanking new to plc programming. everything i know is either self taught or from the AB manual.

im currently building a test rack to verify integrity of plc5 cards as we now rely 100% on refurbs and rebuilt units.


i have 2 8slot chassis with an assortment of cards in them. currently im connected up to the processor via a USB driver and RS232 plug.

Right now im only working on the chassis with the processor. i had planned this job out by calling the chassis with the processor rack 01. i have all the field wiring done and all my reverse tagging and drawings have it layed out as rack 01.

somehow i have the 8 slot chassis addressed as rack 00. my program works fine if i change all the IO addressing from O:015/0 to O:005/0.

How do i change the rack number from 00 to 01?
 
Welcome to the PLCTalk forum community !

You chose a pretty obscure topic for your first post, and I was about ready to say "it can't be done", but took a second thought and found an RA Knowledgebase document on the topic, Answer ID 19446 (Access Level: TechConnect).

The old PLC-2 controllers used Rack 01 as the first addresses, while the PLC-5 used Rack 00. When you migrated from PLC-2 to PLC-5 you could end up in a situation where you either had to re-address or re-label a bunch of your I/O modules and wires.

The PLC-5 controllers have a Status file setting that lets you account for this issue. Set bit S:26/02 = 1, and the processor-resident chassis will be addressed as Rack 01.

You can find this mentioned in the Quick Reference; search for "S:26".

Again, welcome to the PLCTalk forum community !
 
welcome to the forum ...

just a quick word of advice ... don't change the default rack assignment ... you don't want to start out on your journey of discovery by putting yourself "out of step" with the vast majority of PLC-5 systems that have been installed over the years ...

another tip: set the chassis dip switches for "one slot" addressing to begin with ... then as you learn more, you might want to change over to the "two slot" or to the "half slot" mode ... (you might want to check and see how your plant's systems are configured - and try to match that) ...

good luck with it - and have fun ...
 
"Back in the day......"

This thread reminds me of a project (2 projects actually) where I had to deduce the I/O configurations purely from panel photographs and the PLC5 code.

There simply was never an opportunity to look at the chassis and I/O adapter DIP switches to see the settings.

It turned out that there was a varied assortment of 2-slot, 1-slot, and 1/2-slot addressing, with the occasional gotcha of some complementary chassis. If I remember correctly there were 9 or so remote I/O panels. Each of the systems had many years of upgrades, so the SI's had to shoe-horn any new I/O in where and how they could.

Yes, it was challenging to sort out, but the only logical outcome revealed itself.

We put all that PLC5 I/O onto a new Contrologix platform using DHRIO modules, the PLC5 in the "master" chassis replaced with a new ASB, and all was good to go.
 
thanks for the help!! changing the S26 bit worked perfectly. now i just need to get my 1771 asb module communicating...
 
thanks for the help!! changing the S26 bit worked perfectly. now i just need to get my 1771 asb module communicating...


What problems are you having ?

Never had any issues with them not working .....
 
This is a New installation and also sort of a first for me. In the past I’ve always used dh+ to connect all the io to my laptop. For this application I’m trying to connect to the processor via the 232 port and then establish communication from the processor to the ASB modules via dh+. I’m using channel 1b and have the light kit up green but I don’t get any lights on the asb module.
 
This is a New installation and also sort of a first for me. In the past I’ve always used dh+ to connect all the io to my laptop. For this application I’m trying to connect to the processor via the 232 port and then establish communication from the processor to the ASB modules via dh+. I’m using channel 1b and have the light kit up green but I don’t get any lights on the asb module.

You're trying to connect to a RIO module with DH+, even though they are different protocols?
 
Yes. Although it sounds like this may not be possible. If i can confirm its not doable i think the next option would be to try and get my boss to spring for a 1784-U2DHP adapter. anybody have any positive or negative experience using those?
 
You didnt write exactly the type of PLC5 CPU you are using.
But almost definitely it will have at least one port that can be setup for DH+ or RIO. So yes, you should be able to test your remote chassis with your current setup.

How is the remote chassis setup in the PLC5 configuration ?
How are the dip switch settings in the remote chassis (SW-1 and SW-2 in the ASB adapter and SW-1 in the chassis) ?

If you are going to test refurbished cards in the future, I suggest you setup the chassis for ½-slot adressing. In that way you can test any type card, one card at a time and you dont have to change any switch setting. Just install the card and use the I and O bits assigned to the slot directly. For analog cards you may have to update the block transfers.
 
Just as a refresher, RIO (Remote I/O) and DH+ (Data Highway Plus) use the same type of cable, but they are different networks and use different protocols. I'm guessing you simply misspoke.

Using the RS232 port isn't an issue. You can do all of this through the serial port. It is slow but it works just fine. I wouldn't buy the U2DHP unless you can find one cheap.

  • DH+ is used for talking with other PLCs, computers, HMIs. But not I/O.
  • RIO is used to allow one PLC to communicate with remote chassis, VFD, sometimes an HMI. But not a computer, and generally not other PLCs.

With the lights OFF on the ASB module that would tell us that it has not been configured to be part of a scan list for any PLC.

The ASB module and the remote chassis have a number of dip switches that must be configured. Have you gone through the manual and configured those properly?

Then in the PLC-5 you must have a channel configured for RIO. You mentioned Channel 1B which makes me think it has been configured for RIO. Channel 1A is the default for DH+.

In the channel configuration you must add the remote chassis. You can enter the information manually or if you are online there is an automatic configuration.

To really help you, we would need the dip switch settings for the remote chassis and for the ASB modules.

OG
 
at a minimium i checked my dipswitches 3 times before i posted on here. But i guess 4th times a charm. when i went to write down the switch settings i noticed i had the ASB module set to rack 01. switched it over to rack 02 and the green light lit right up.

Your correct i am using RIO. thanks for the clarification. im learning this all on the fly and honestly didn't know the difference. all my discrete I/0 testing is now functional.

Thanks again for all the help! im sure ill be back with more questions as i muddle through getting the IFE/OFE, IXHR, and IR cards operational!
 
at a minimium i checked my dipswitches 3 times before i posted on here. But i guess 4th times a charm. when i went to write down the switch settings i noticed i had the ASB module set to rack 01. switched it over to rack 02 and the green light lit right up.

Your correct i am using RIO. thanks for the clarification. im learning this all on the fly and honestly didn't know the difference. all my discrete I/0 testing is now functional.

Thanks again for all the help! im sure ill be back with more questions as i muddle through getting the IFE/OFE, IXHR, and IR cards operational!


Interesting that when you use the "blue hose" for RIO, the wire colours are reversed to what you would wire for DH+....

I'm guessing it was done so you could tell what the connection was, without going into the configurations.

But to be honest the wires don't know, and don't care, what colour sheathing they are wearing ...
 

Similar Topics

Hi, i need help, i have a plc 5/80c 1.5 and the i/o config is: Local chassis (4 slots) onnly the processor and also 4 chassis each (16 slots)...
Replies
1
Views
1,466
My goal is to get an analog signal from a SLC-500 remote rack back to a PLC-5 main rack. Is this possible? If so, I may need some help. I've set...
Replies
4
Views
1,743
Hello, I have a potential project and I am rusty in communication skills. The project will consist of a Control Logix platform with an existing...
Replies
17
Views
6,289
Curious if this is possible. I am working on a PLC5 to CLX conversion. Due to panel space limitations and time I need to replace a small PLC5...
Replies
4
Views
3,474
I am looking for a bullet proof UPS that can handle temps up to 60 deg C. This is a remote rack at a pumping station. When power is lost, we loose...
Replies
10
Views
3,533
Back
Top Bottom