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-   -   Lenze ESV22N02YXB571XX1A10 Drive and Modbus RS-485 (http://www.plctalk.net/qanda/showthread.php?t=113273)

Levi G December 7th, 2017 11:52 AM

Lenze ESV22N02YXB571XX1A10 Drive and Modbus RS-485
 
1 Attachment(s)
Hi I am trying to communicate with this Lenze drive I have kicking around.
My PLC is a Productivity 1000.

This drive has a built in Modbus module with a RJ-45 connector. This is not the plug-in Modbus module. I can not seem to get a hold of the pin-out for this RJ-45 connector. Lenze tech support says this drive was custom made for Captive Aire and they don't know the pin-out. Has anyone had any success communicating with this drive before? If so could you provide me with the pin-out of the RJ-45 connection. I have the manual and it says it is for Modbus RS-485 Daisy chaining.
Attached is the picture of the Modbus comms

gclshortt December 7th, 2017 03:14 PM

If it is a standard Modbus Connection then the following PDF will show you the Pinout:
http://www.modbus.org/docs/Modbus_ov...al_line_V1.pdf
Pin 4 - +
Pin 5 - -
Pin 8 - Gnd

Regards,

danw December 7th, 2017 04:36 PM

Is it likely that Modbus RTU over RS-485 is the only signal on the RJ-45? Probably. If that's the case, then it is a known fact that swapping the driver lines will not damage the driver lines. Comm won't work if the lines are swapped, but there's no damage. So you can break out those lines and give it a try.

You might be able to confirm the signal GND by testing for continuity to the frame ground. It might or might not be the same point.

If those pins 4 and 5 do not modulate when Modbus is polling, then use a voltmeter to check for which pins modulate/oscillate when Modbus is polling. It is very likely too be 2 wire half duplex and only 2 wires out of the 8.

Levi G December 7th, 2017 04:50 PM

1 Attachment(s)
I will give this a try later today and report back
What is the "T" Terminal for on the P1000 when using RS-485? (see attached)

I have never worked with Modbus before so I really appreciate the help

danw December 7th, 2017 06:04 PM

I've seen dozens of RS-485 connections before:

Here's a handful of them:

https://s2.postimg.org/gk4t0r0i1/RS_...d_labeling.jpg

None have a termination terminal.

I have no idea what its purpose is. Termination resistors are installed directly across the (+) and (-) driver lines.

Levi G December 7th, 2017 07:42 PM

Ok, I tried glcshortt's suggestion and it's working like a champ.

Thanks for the help guys. :site:


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