Issue
The PME system log is filled with repeating "Site connected" messages, making it difficult to navigate and maintain the system log.
Product Line
Power Monitoring Expert 7.x
Power Monitoring Expert 8.x
Power Monitoring Expert 9.0
Power Monitoring Expert 2020
Power Monitoring Expert 2021
Power Monitoring Expert 2022
Power Monitoring Expert 2023
Power Monitoring Expert 2024
Environment
System Log Events
Cause
Some Modbus TCP devices quickly close idle connections resulting in PME frequently establishing a new connection with the device.
Resolution
Use the VIP to frequently poll a register to serve as a "keep-alive" so the device doesn't close the connection.
1. Review the "Site connected" messages in the system log and take note of each unique site and/or device mentioned, in this example it's occurring with 2 sites "Sub6_XMFRS" and "Sub7_XMFRS":
2. Open and log into Designer.
3. Go to File > Open and select a VIP, this example will use VIP.DEFAULT:
4. Click and drag an Arithmetic Module onto the diagram:
5. Click on the small blue input circle on the Arithmetic Module then select "NEW Source":
6. With the dotted line following your mouse, click on the ION button on the top toolbar:
7. Link to a register either on a device or a device under a site that has recurring "Site connected" messages. In this example it's a site so the link will be to a serial device added to the site:
8. File > Save the VIP, then do shift+left-click on the input circle of the Arithmetic Module to confirm a value is displayed. Note: if linking a serial device under a site and "n/a" is displayed instead of a value, try linking a different serial device that is communicating. If the linked register is not displaying a value, it won't prevent the "Site connected" messages.
9. Repeat for remaining devices and/or sites that have recurring "Site connected" messages.