RS485 S7-1200 to Danfoss FC102

CallumMacEwen · Jul 5, 2016

Hi all,

I am trying to set up a S7-1200 with a RS485 adapter to communicate as a MODBUS master to a Danfoss Drive. I am not very experienced with using MODBUS and was wondering if anyone out there could shed some light into what I should be doing.

The bit I am struggling with is how to set up the instructions on TIA Portal. I think I need to use the MODBUS master and the MODBUS Comm Load instruction.

(8{)} ( .) · Jul 5, 2016

Step #1 is to post to PLCs.Net and ask for help.
Step #2 is to use ModScan and and RS-485 converter to make sure that the drive is communicating correctly. Test the control bits and the speed command in order to understand exactly how to run your VFD (VLT).
Step #3 is to download sample code from Siemens and modify it to match your application.
Step #4 is to integrate the working sample code into your program.
Step #5 is to have a beer.

Good Luck,

Yosi

CallumMacEwen · Jul 5, 2016

I dont have aRS485 converter to be able to do that.

I have obtained the Siemens code and have that working ok, I am still struggling to work out how to address the drive properly. DO I need to use HEX instead of binary?

rgua · Jul 5, 2016

I don'know Fc102.
For danfoss FC51 and FC101 and simatic 1200 I used these parameters:
Start (hex) 047C
stop (hex) 043C
reset (hex 04BC
controlword (decimal) register 42810 ( send start/stop/reset)
referenceword (decimal 1/100 Hz)) register 42811 (send frequency)
statusword (decimal) register 42910 (read status)
freq-feedback decimal (1/100 Hz) register 42911, ( read ferquency, feedback)

VFD parameters:
8.30 protocol [2] Mbus RTU
8.31 address (decimal)
8.32 bitrate (as simatic rs485 port)
8.33 parity/stop (as simatic rs485 port)

(8{)} ( .) · Jul 7, 2016

I highly recommend getting an RS-485 converter. I have an ADAM 4520 but there are plenty out there. Important to get a proven device. I do recommend the ADAM though and if money is an issue you can pit up used ones on ebay. Here's a link:

http://www.advantech.com/products/d...4520/mod_8dcee4b7-fbde-4c5d-9752-ed2f2fbd00bf

There are also USB-RS-485 converters which give you a little less flexibility but if your PC doesn't have an RS-232 port this is a simple way to go.

Another alternative I've used is TCP/IP -> RS-485 converter going through a virtual com.

Either way it's an important thing to have.

Good luck,

Yosi

orthodudz · Aug 8, 2016

rgua said:
I don'know Fc102.
For danfoss FC51 and FC101 and simatic 1200 I used these parameters:
Start (hex) 047C
stop (hex) 043C
reset (hex 04BC
controlword (decimal) register 42810 ( send start/stop/reset)
referenceword (decimal 1/100 Hz)) register 42811 (send frequency)
statusword (decimal) register 42910 (read status)
freq-feedback decimal (1/100 Hz) register 42911, ( read ferquency, feedback)

VFD parameters:
8.30 protocol [2] Mbus RTU
8.31 address (decimal)
8.32 bitrate (as simatic rs485 port)
8.33 parity/stop (as simatic rs485 port)

Hi sir,

Im newbie here, but it happened that currently i have project that involves modbus communication with danfoss drives.

How did you get these registers (42810, 42811, 42910, 42911)...?
I've read manuals for FC51 and FC101 but i couldn't see any of these registers you mentioned.

Your answer will help me alot...

Thanks in advance sir.

rgua · Aug 8, 2016

older revisions had adress as 50000 Input data (ConTrolWord) ...

from "Design Guide VLT Micro Drive FC 51"

In VLT Micro Drives after the software version 2.32 the new
feature has been implemented by copying the Input/
Output data to also be available in a lower holding register
areas:
02810 Input data Frequency converter Control Word register(CTW)
02811 Input data Bus Reference register (REF)
02910 Output data Frequency converter Status Word register(STW)
02911 Output data Frequency converter Main Value register(MAV)
Table 8.34 Lower Register Numbers for Input and Output Data

add 40000 for Modbus compatibility.

RS485 S7-1200 to Danfoss FC102

CallumMacEwen

Member

(8{)} ( .)

Lifetime Supporting Member

CallumMacEwen

Member

rgua

Lifetime Supporting Member

(8{)} ( .)

Lifetime Supporting Member

orthodudz

Member

rgua

Lifetime Supporting Member

Similar Topics