I am trying to read up to 15 gas monitors, via Modbus using MB_CLIENT. I have no problem communicating with the first one, but when adding further monitors, these go into error 16#80C8. The help information shows the error as below:

• No response of the server in the defined period. Check the connection to the Modbus server. This error is only reported on completion of the configured repeated attempts.
• If the "MB_CLIENT" instruction does not receive an answer with the originally transferred transaction ID (see static tag MB_TRANSACTION_ID) within the defined period, this error code is output.

I cannot work out how to rectify this error, as all settings for the further gas monitor MB_CLIENT blocks are the same.

Any help would be greatly appreciated.

Hello,

user

I cannot work out how to rectify this error, as all settings for the further gas monitor MB_CLIENT blocks are the same.

to me this is your problem.

Can you be kind better explain what your idea about data collect is? You have 3 options

1. one MB_CLIENT handle all Servers continuesly one by one.

2. more MB_CLIENT blocks but here it is limitation of connection resources that can be used at same time for more Servers connection.

3. some mix of 1-st and 2-nd option, simply more CLIENT blocks collect same number of servers at one time and then collect data with next same number of rest of Servers.

I think you handle your code with Servers wrongly.

Hi Swarley92,

Thanks for that information. The status code is 16#80C8 and the analysis is in the first post. I know what the status means but am unable to fix the code.

I will update this topic as I know more.

Cheers

Good afternoon Ivan,

I had come to the conclusion myself that I should interrogate each server in turn. At first I was attempting to poll each server at the same time.

I will try this and update the thread accordingly.

Cheers

Hi Ivan,

The problem was with the connection identifier in the CONNECT TCON_IPv4 parameter. After assigning each station with a seperate and unique identifier the issue has been resolved.

Many thanks for your time.

Cheers

Hello,

yes, that is that problem as i said, you can't have same cfg for each Client, especially connection ID because then you can't use more Client blocks independently at same time. Glad you have solution.

Thank you for your description about solution because it can be helpful to other users. All best...