Showing results 1 to 5 of 5

Thread: Modbus TCP slave address

  1. #1
    Join Date

    Default Modbus TCP slave address

    I have one modbus TCP unit. I've tested communication with this unit via "AVReporter Modbus Communication Tester" . All ok, all working.

    But in Zenon 7.11 EE I've used MODRTU32 driver and can't read any variable (function 3, Holidng register)

    I checked, that in Modbus TCP tester i use Slave Address=1(when i set it to 255(0xFF), my unit stop answering). But in MODRTU32 i can't set or check, what slave adress is have used.

    Can i set slave addr in modbus tcp driver?

  2. #2

    Default Re: Modbus TCP slave address

    Hi Diemon,

    In the MODRTU32 driver, when you create a connection and enter the IP address, the "Net address" field should correspond to the Modbus Slave ID.

    Use this same Net address from the driver configuration at the Net address property at the holding register variables of the MODRTU32 driver, to establish the connection between the variable and the connection in the driver configuration. (this way you can configure multiple slaves with identical or different IP addresses in one driver)

    Best regards,

  3. #3
    Join Date

    Default Re: Modbus TCP slave address

    Thx, markclemens, it's working.
    But i dont understand, how i can "configure multiple slaves with identical or different IP addresses in one driver"?
    I need to add 5 modbus units with Slave ID=1 but with different IP adresses. In my mind, i need to create 5 different MODRTU32 drivers(because i cant create 5 connection with "Net address"=1 in one driver)

  4. #4
    Join Date

    Default Re: Modbus TCP slave address

    Hi diemon,

    you are right - you cannot have more than one connection with the same Net address in one driver instance (therefore you cannot configure connections to two - or more - Modbus Slaves with the same slave address in one driver instance).
    For this, you will need to create new instance(s) of driver.

    FYI: In zenon Operator license you can only create "one instance" of driver, as mentioned in the documentation:
    Manual -> zenon Operator -> Restrictions for the zenon Operator


  5. #5
    Join Date
    Salzburg, AT

    Default Re: Modbus TCP slave address

    In zenon Operator you can take MODBUS_ENERGY driver instead MODRTU32. The MODBUS_ENERGY driver the Net Address and Slave ID are independent settings. So in M_E driver you can have in one driver instance 5 connections (to 5 IP+Port combinations) communicating then with 5 slaves having the same ID, e.g. all ID=1.

    But the M_E driver belongs to higher price group.

Similar Threads

  1. command using Modbus TCP/IP
    By ziadnajjar in forum Drivers
    Replies: 8
    Last Post: 21st February 2018, 11:15
  2. Kommunikationsproblem mit ModBus TCP
    By schroder in forum Drivers
    Replies: 3
    Last Post: 5th August 2013, 16:58
  3. Replies: 1
    Last Post: 1st April 2013, 22:28
  4. STRATON controling Modbus TCP slave bus controller with IO's
    By barszcz in forum straton / zenon Logic
    Replies: 3
    Last Post: 24th February 2013, 00:30
  5. Real Variable Modbus TCP
    By pkreisel in forum Drivers
    Replies: 1
    Last Post: 15th February 2011, 23:39

Posting Rules

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts