Using AB Powerflex 700 with MODBUS??

Hi, I was wondering if somebody could kick start me in the right direction. I am trying to setup control between a Allen Bradley Powerflex700 to Micrologix controller 1100.

I got the impression that I can control the powerflex 700 drive using modbus, by communicating using MSG commands within the RSLogix500 code. I saw a tech note from AB saying it can be done using the Powerflex 4/40 range, would the same technique be used for the Powerflex 700??? or do I need to buy an additional adaptor like a 20-COMM-M for the 700 drive. From the tech note they say that the Modbus 4/40 Drive can be connected via a 485\RS232 AB special connection (1763-nc01)and this is what I was planning on using.

Would anyone have any experience in the above. Would appreciate any advice on this. Many thanks -Rpax

Have never used MODBUS with a PF 700 myself, but the 20-COMM-H supports MODBUS RTU, Metasys N2 and Siemens P1 FLN protocols.

The PowerFlex 4/40 family has a native RS-485 Modbus RTU protocol port on them; the A-B "DSI" protocol includes several Modbus RTU command functions, so you can use Modbus very simply with the PowerFlex 4, 40, and 400 drives.

The PowerFlex 70/700 drives have a native interface that is much faster and more powerful than Modbus, called Drive Peripheral Interface (DPI). All fieldbus connections to PowerFlex 70/700 drives must use one of the DPI interfaces.

Depending on the DPI fieldbus interface module you select, you could use the MicroLogix 1100's serial port to command the PowerFlex 700 using Modbus RTU (20-COMM-H), or DF1 Full Duplex (1203-SSS) or DF1 Half Duplex (20-COMM-S), or you could use EtherNet/IP (20-COMM-E) on the MicroLogix Ethernet port.

If it were my project, I'd hardwire the Start and Stop functions and only use the network for frequency reference and feedback.

Why Modbus?

You might have a perfectly good reason for usin Mbus that you didn't state but these drives integrate very nicely with AB PLC's using RIO, control net, and Devicenet. Are you stuck on Modbus?

Hi, firstly really appreciate your feedback on the above, so thanks for that. The reason for using Modbus is that it was specified by the vendor but probably only because they thought it would be the easiest and cheapest way of integrating if similiar to the 4/40. They had actually given me the tech note on how they wanted it done. If the above won't work then I think any of the other networks would be fine.

So, if I have to go with another method of integration would i need to buy a new DPI Drive Inteface whether Modbus, DeviceNet etc. Is it possible to set the Micrologix1100 PLC Up as a Master Slave relationship to the Drive using AB Network software i.e RSNetworx for either Ethernet/IP, DeviceNet etc. If so do I need to buy an additional Master module for the Micrologix1100. Just not that fimiliar with both devices. Again thanks for feedback