micrologix and power flex drives

I was wondering if anyone knows a good link/ resource that explains how to program a micrologix 1400 to control a Power Flex 4 drive via RJ45 connections.
The idea is to control 4-7 drives independantly using the plc. Other then the drives, there will only be a few opto sensors linked to the plc

thanks in advance for the help

We use this type of connection a lot but I can't find just one source of information. I guess we have developed through various stages. I'll assume you mean to use the serial port.

Make sure you have the full Powerflex manual. Near the end (Appendix C) it breaks out the addresses for locations you can write to and read. Note that, in the messages within the Micrologix we had to use an address one higher than listed in the documentation. This happens a lot in Modbus.

You will set up the Micrologix port for Modbus RTU Master. Under 'Protocol Control' - 'Control Line' select 'No Handshaking (485 Network)'

Use a 1763-NC01 cable to break out the A/B data lines and the ground. Use a AK-U0-RJ45-TB2P RJ-45 connector to break out the two data lines on the Powerflex. Place a terminator resistor across the drive which is last physically on the network.

On the Powerflex set parameter P38 to '5' to allow speed control through the Modbus port. Set P36 to '5' if you want to issue Start/Stop commands through the port (I don't advise this)

Set A103 to the desired baud rate. To match the default in the Micrologix set it to 19,200 (option 4). You will set A104 - the unit address - to a unique number on each drive. It would be best to just work with one drive at first so you can leave the 100 default. We set 'Comm Loss Action - A105' to 3 - Continue Last. This helps prevents a lot of faults when getting going.

Next will be the messaging. Get this PDF I know it's for a Micrologix 1500. Ignore the stuff showing it using a Net-AIC. You already have this covered with the NC01 since the 1400 has RS485 drive already built in. Follow its programming examples.

Check back as you get into this. While not a fast as a dedicated motion communication network its fast enough (I would say with 7 drives you can update and get status feedback from all 7 in less than 1/2 second). It's a very robust and forgiving network.

Hi,

If you search on here you will find several threads already relating to the very thing you need (i'm pretty sure i've posted a couple of things to do with the subject). You could also search the Rockwell KB for several examples of sample code/drawings etc.

There will be several alternative opinions of just what exactly should be controlled via the Modbus network, but that's for you to determine with your particular application.

If you use the 1763-NC01 then the physical connections are made a little easier (8-pin mini din to 6 pin Phoenix style terminal block with direct connection to the A-B pins).

You will need to use the MSG instructions to create the communication with the drive. The user manual will detail the relevant Modbus registers to READ/WRITE from your MSG blocks.

We've done several applications using the ML1100/ML1400 talking to a Powerflex drive via Modbus, and it works quite painlessly (once you've tackled the basics!!).

Hope this helps.

Rob

1-0 to Bernie!! (must type faster!)

Rob

Thanks - I had my morning coffee (It's still morning here). By the way, with RS485, if everything else looks fine but you don't have communication try swapping the data lines.

I forgot to add, after setting up the parameters on the Powerflex cycle power once. Some of them don't take effect until after the power reset.

Here is a logic program for the ML 1100. connected to the PF4.
Hope this helps