In certain industries, processes can’t shut down as doing so would lead to loss of production or in extreme cases damage to the production line. In these situations, the more you can do while the production line is running, the better off you are. Allen-Bradley has had robust online program editing for decades, as well as I/O support for RIUP (removal and insertion under power,) but the online addition of I/O in the ControlLogix family is a more recent development.
When adding I/O online on ControlNet, the I/O is placed in the unscheduled bandwidth portion of the “Network Update Time” (aka NUT) which would be more than adequate for most process applications, by may not have the update rate and repeatability needed for high speed applications.
Note: For details about v15’s support for adding 1756 online in remote run, please reference the following manual from Allen-Bradley (A-B:)
The second phase of support for adding I/O online with ControlLogix came with version 18. This version added many new devices to the support list, including:
- 1756-CN2, 1756-CN2R, 1756-CN2RXT
- 1756-EN2t, 1756-EN2TR, 1756-EN2TRXT, 1756-EN3TR
- PowerFlex 4, 40, 400, 400P
- PowerFlex 70, 700, 700s, 7000
- PowerFlex 753, 755
- PowerFlex DC
- 1305, 1336E, 1336F, 1336R, 1336S, 1336T, 1397
- 1757- FFLD
Note: For details about v18’s added support for adding devices to a ControlLogix system online in remote run, please reference the following manual from Allen-Bradley (A-B:)
I hope you’ve found the above information and links about adding I/O online to a ControlLogix helpful. If you have a question or comment please use the “Leave a reply” form below to comment on this article.