Samba Modbus connection to SEW VSD

[Buddy123]

Hi

I am trying to connect a Samba PLC to a SEW MDX61B VSD via  Ethernet and using Modbus TCP.  Using the function blocks in the Samba program I can get it to connect to the SEW  VSD but when I try and read an address which the SEW guys say is correct, 8320 which is the encoder position it shows a status fault code of 7. I can connect the same program to a Jazz PLC and read an address in it.

The Samba is the Master and SEW the slave, can someone help, I think it looks like a case of just the wrong address or maybe an extra number before it

Thanks Phil

[kratmel]

Hi, maybe you have the latest firmware in in Samba.

Please use Visilogic 9.8.65 and download firmware from this version for test. Write back about the test results

Some tips in topic

 

[DanT]

Hi;

Have you reviewed how VisiLogic  Handles Modbus register addressing?

MODBUS Help is hard to Find in Help, but start here:   ( there is a lot of info there- just well hidden )

                                                                  Help, Index,   MODBUS

  Find and look at Slave Addressing.  Notice the SAMBA ( Vision Color) addressing is  set up in HEX ( Base 16)

     Know how to convert  Decimal to Hex and   back   -- Unitronics will do it automatic , but beware !

          in the example illustrated     7028  is Hex  0x7028     =   28712 decimal

     So is  8320   Decimal or Hex?          8320 Decimal =   0x2080 ( H-2080)

                                                                                0x8320 Hex      =     -31968 decimal    ( MI's are Integers  +/-  32767)

   Just something to consider

DanT