ION9000 Modbus issues

[Gladwin]

Hi Team,

When the Modbus TCP connection is established with the meter on port 502, the connection is successful.
However, once a data poll is initiated, the response times out and the meter immediately closes the connection on port 502.

As a last resort, I attempted updating the firmware to the latest version, but this did not resolve the Modbus TCP communication issue.

can please advise on this 

Gladwin 

[Mehran_Mehrnia · Accepted solution]

Hi @Gladwin 

Here are the possibilities I recommend verifying:

• Modbus TCP Timeout: Check the Modbus TCP Idle Timeout; this is the number of seconds the meter maintains a connection after it becomes idle. Note that a setting of 0 disables the timeout feature.

• Security Settings: In the security settings, ensure Modbus Map Access is not set to 'None'. If this parameter is set to 'None,' the meter may return an 'Illegal Data Address' error or reset the connection.

• Unit ID: Verify the Unit ID (Slave ID). If the Modbus Gateway is enabled, the preferred Unit ID is typically 255.

• Protocol Status: Confirm that Modbus TCP is explicitly enabled on the port.

• Register Range: Invalid Register Requests: Ensure your software isn't polling a range that doesn't exist.

• Network Interference: Firewall/IPS Interference: An intermediate switch or firewall might identify the Modbus 'Read' command as a threat and terminate the TCP stream.

Best Regards,

-Mehran

L3 Expert Advanced metering

[Gladwin]

hi, thank you this worked