explicit start/stop commands to AB Powerflex

[DMG]

Hello, I'm trying to used a BRX to control some AB Powerflex 525 drives. I understand how to send and get parameters to the drive using explicit messages, but I can't figure out how to send the start and stop commands. From what can tell from the AB manual and from their support site is that I need to write data to N tables using PCCC objects. I don't understand what attribute to address to send these commands. Can someone point me in the right direction? Am I way off in how I'm approaching it?


The AB Knowledge Center has a process outline for how to do this. For example, as previously mentioned, I don't know how to translate the N42:3 value into an addressable attribute:
...Firstly we need to send a timeout value to the drive (in seconds), before sending any control data. The N42:3 value normally defaults to 0, and so needs a non 0 value before it accepts any valid control data. If this value is not changed from 0, the other message write (to N41/N45:0) will error out. This timeout value is stored in RAM. If the drive is powered cycled, this value must be written again.

The screenshot above details a value of 5 (seconds) in N20:0 which will need to be sent to the drive...

...Now we can send the Logic Control and reference words. The user manual details these starting from N41:0 (IMPORTANT: there is a misprinting on PowerFlex 525 Embedded EtherNet/IP Adapter User Manual Publication 520COM-UM001B-EN-E - March 2013 page 136, N-File address for Reference should be N41:2). The user program (detailed later in this application note) writes the control data for the Logic Control word at N20:20 and the Speed Reference at N20:22....

Based on the above (after writing the timeout value to N42:3) and the logic command words table from the manual (stop word "1", start word "2", etc...) would be written to N41. Is it just that 41 is the attribute I send these messages to?

[franji1]

You are confusing the BRX N memory with the AB N memory.  They have nothing to do with each other.

Your AB documentation should talk about EtherNet/IP(tm) class/instance/attribute, not N memory.  I'm guessing you are looking at how to use DF1 or some AB protocol to do what you need (since it mentions AB N memory, but not EtherNet/IP protocol nomenclature).

I would recommend you post on A/B's forum or Automation Direct's Community forum to nail down the EtherNet/IP details.  Once you know all that, then we can figure out how to map that EtherNet/IP class/instance/attribute details into Do-more EIPMSG instruction(s).

Someone on this forum may know, but you need a much wider audience that knows your AB device details.  You can also take the shotgun approach and post it on all 3! (you just need the answer, you don't care where the answer comes from)

[Controls Guy]

See if this document is helpful:

https://literature.rockwellautomation.com/idc/groups/literature/documents/um/520com-um001_-en-e.pdf

[jwbaker3]

There is a video on the ADC support page on how to set up ehternet/ip  Domore to a powerflex 40. https://youtu.be/_NoMHDMfZ7Q (This is the url)  copy and paste in the address bar or go to the ADC support/video page and search for powerflex 40. This should help you get started. You will have to look up the class/instance/attribute for the drive you are using.  I have done some AB with the Domore/205, but I have done a lot of installations with Yaskawa drives and BRX it works great. Hope this helps AB is not straight forward with there information.

JW

[franji1]

Someone on this forum may know, but you need a much wider audience that knows your AB device details.  You can also take the shotgun approach and post it on all 3! (you just need the answer, you don't care where the answer comes from)

Looks like we have some experts!!  THANKS TO JWB and CG!

[DMG]

Thanks for all the help. After speaking with AB and automationdirect, unfortunately it looks like the BRX is not capable of sending the messages to the drives. I'll have to do it using a Productivity series unit with implicit commands.

[Bolt]

Here's a https://forum.hosteng.com/index.php?topic=2998.msg23799#msg23799 to a post where they have been able to make it work with a BRX.

[Controls Guy]

Here's a https://forum.hosteng.com/index.php?topic=2998.msg23799#msg23799 to a post where they have been able to make it work with a BRX.

Well, that's a different adapter, so maybe not transferable, but that PDF I linked showed limited explicit MSG capability from an AB controller to a 525.   If it can do explicit at all should work from a BRX.  Looks like it may be only one parameter per transaction, but for start/stop, that's fine.   Kind of clunky for reading status but doable.