Jump to content

Jazz JZ20-J-R16 and MJ20-RS modbus Slave RS-485 problem


Recommended Posts

Hi

I'm trying to configure Jazz JZ20-J-R16 as a SLAVE.  I've got Jazz JZ20-J-R16 (O/S Version 2.44) and Modbus module MJ20-RS.

And I'm trying to read some registers using Modbus Poll soft and ADAM-4561 converter. The Modbus Poll and ADAM works well, I can read data from another SLAVE device.

I did everything according to the manual (table from Help). The SB141 is set to 1, I can see it on the display. I am not trying to use two ports simultaneously,

only RS-485 is connected when I'm trying to read data from PLC.  When I'm trying to read data using Modbus Poll, there is "TimeOut" error.

Interestingly, when I change the connection of the communication cable (A and B), the Data Bits in PLC changes from 8 to 7, and in Modbus Poll soft is "Insufficient bytes recieved" error.

 

My ladder program is attached:

image.png.c861aa5c6d0fcd55e85f558ca54e5aea.pngimage.thumb.png.10cff10d860c4ef7cb3e0fdaae3c3a4f.png

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

This site uses cookies. By clicking I accept, you agree to their use.