Slc 551 - dnet - pf755

Vintage L551 - series C - FRN 5. SDN is same vintage.

Replacing old 1336 with PF755, which so far hasn't been much of an issue on the programming side.

Easy to write all command bits to drive, read status bits, set speed in RPM and read speed in RPM.

Here are a couple of screenshots, and this all works.

Problem is, I need to be able to read motor current, and not sure how, or if possible to get it from the drive to PLC over Device Net.

Data links? Any ideas?

Thanks!!

Data Links are by far the easiest way to read the output current from the drive.

Doing explicit messages with an SLC and 1747-SDN that old would require the painful old structured buffer logic. I recommend against that.

I don't have RSNetworx for DeviceNet handy right now, but in general you enable an Input Data Link, link it to the desired parameter, and enable it to be part of the Master/Slave I/O connection.

Then you expand and re-map the Input data connection on the DeviceNet side.

Thanks for the info Ken.

This is my first time with A-B Device Net, so there has been a lot of reading and trying things, not to mention the 16-32 bit thing.

I have very little clue how to work with data links at this point.

Original plan was to delete the old drive from the SDN, hard wire the start/stop and a couple other things, then do some messaging for info over Enet. Problem is the FRN is way too old. That should stand for F***** Rong Number!

I'll try sort it out by next Monday, but I ordered an analog input card as a backup, just in case.

This is a little extrusion machine and they need to know current to be able to adjust speed accordingly. Boy, those analog cards ain't cheap!

There are also 10 temperature controllers on the device net as well. It's scattered all over.

Ken Roach said:

...link it to the desired parameter.

Click to expand...

This is what didn't work. No parameters showed up.