expansion I/O racks for ControlLogix

defcon.klaxon

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Hey guys,

I've always believed (maybe I saw it in a brochure long ago) that with AB ControlLogix, you can set up multiple chassis full of I/O cards that all report back to a single processor module via ethernet. For example, let's say I have four racks. Rack 0 is a processor, ethernet module, and various I/O card, while Racks 1-3 have no processor but each has an ethernet module and various I/O cards, and Racks 1-3 all report back to the processor in Rack 0.

However, opening up Logix and trying to set up this topology, I don't really see any way to set up multiple chassis in a single project.

Was wondering if anyone could confirm or dis-confirm what I'm describing, and if it is possible, how would you set it up in Logix?
 
Hey guys,

I've always believed (maybe I saw it in a brochure long ago) that with AB ControlLogix, you can set up multiple chassis full of I/O cards that all report back to a single processor module via ethernet. For example, let's say I have four racks. Rack 0 is a processor, ethernet module, and various I/O card, while Racks 1-3 have no processor but each has an ethernet module and various I/O cards, and Racks 1-3 all report back to the processor in Rack 0.

However, opening up Logix and trying to set up this topology, I don't really see any way to set up multiple chassis in a single project.

Was wondering if anyone could confirm or dis-confirm what I'm describing, and if it is possible, how would you set it up in Logix?

In your project, ADD a 1756-EN2T. When it comes up, it will ask how big a chassis its in, and in what slot. Once the -EN2T is in the project, you can then add modules.
 
I can confirm what you are trying to do is indeed possible. You just need to add all the relevant modules in your hardware configuration to match what you are installing to achieve this.
 
Here's a screenshot of how one of ours is setup.


The processor, chassis 1 and its IO is in one control room, chassis 2 and its IO are in another control room.

0001.jpg
 
On the same topic, is there a reason why you'd want to use a ControlLogix chassis instead of PointIO or FlexIO? I've always used PointIO due to a lower price tag and expandability.
 
On the same topic, is there a reason why you'd want to use a ControlLogix chassis instead of PointIO or FlexIO? I've always used PointIO due to a lower price tag and expandability.


Unrelated to what the OP is asking, but I use the 1769-AENTR and 1769 CompactLogix I/O so that we only have to stock one type of I/O cards. Plus, the maintenance guys are used to that I/O, so its less for them to have to figure out when troubleshooting. It costs a bit more than PointI/O, but it pays for itself in the long run (in my case).
 
On the same topic, is there a reason why you'd want to use a ControlLogix chassis instead of PointIO or FlexIO? I've always used PointIO due to a lower price tag and expandability.

Basically because I have a lot of experience with Control/Compact Logix systems. I'd be interested in checking out PointIO and FlexIO we've just never used them.
 
Basically because I have a lot of experience with Control/Compact Logix systems. I'd be interested in checking out PointIO and FlexIO we've just never used them.


Oh, to have the luxury of Control Logix being my most familiar platform :cry:
 
I have a ControlLogix system I have worked on that for the 4 Ethernet racks they are all SLC500 13 slot racks with SLC cards. Not sure why as the SLC racks are larger, and the SLC cards are older technology.
 
On the same topic, is there a reason why you'd want to use a ControlLogix chassis instead of PointIO or FlexIO?
Point I/O & Flex I/O require a program download if you want to add/modify a module. For some control systems that run 24/7, this is a deal breaker.

1756 I/O, 5069/5380 CompactLogix I/O & (I believe) the new Flex5000 I/O can all add modules whilst online.
 
RIUP v Add Online

RonJohn said:
Point I/O & Flex I/O require a program download if you want to add/modify a module. For some control systems that run 24/7, this is a deal breaker.

1756 I/O, 5069/5380 CompactLogix I/O & (I believe) the new Flex5000 I/O can all add modules whilst online.

But what about physically?

To make the above distinction...

You can add all those online in a Logix 5000 project. But of that list, you can only Remove and Insert Under Power (RIUP) 1756 I/O and the new Flex 5000 I/O modules. The 5069 CompactLogix I/O modules do not support RIUP. You must power down to physically add them to a local controller. Similarly, you can add 1746/7 SLC I/O modules to an online Logix 5000 project but they too do not support RIUP. But for both these, if adding them as distributed I/O to a Logix 5000 project, then you can add them online and Inhibit the modules. When you power the distributed I/O up and they are connected to the local controller you can then remove the Inhibit for the modules.

1734 Point I/O and 1794 Flex I/O modules do support RIUP, but cannot be added to a Logix 5000 project while online.

When performing RIUP for existing modules, you should make sure that "Major Fault on Controller if Connection Fails While in Run Mode" is disabled under the module properties and it's also good practice to Inhibit the module on a running system.

For 1756 I/O (r15 or above), Flex 5000 I/O, 5069 I/O, 1747 I/O, certain Ser/Rev PowerFlex Drives (r17 or above AOP Online Import) and other devices that do support online addition, the processor keyswitch must be not be in RUN mode. Remote Run, Remote Program, or Program mode is required.

Some 24/7 facilities are quite strict on the keyswitch being left in RUN mode and removed (where one exists) at all times while running. But for those less stringent, online addition is definitely an important factor in deciding which I/O platform to go with.

Regards,
George
 
so what does this system control - and how dangerous is it? ...

yes, Ethernet is easier - and cheaper - to set up ...

but ...

personally I've never heard of an "offshore oil drilling platform" making use of Ethernet ... every one that I've ever run across uses ControlNet instead ...

I wonder if there's a reason for that? ...
 

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