General Port Properties

Use the General properties to enter general information for the port. You can define the following:


Enter an optional description to help you identify the port.

Scan Rate

Enter the base scan rate for the port. Point scan rates will be multiples of the base rate.

You can specify a scan rate in Ticks (100 ticks = 1 second), Seconds, Minutes, or Hours.

Retry Count

If communications cannot be established for a device on the port, the device is considered to be down, and a $DEVICE_DOWN alarm is generated. Once a device is down, periodic attempts are made to resume connections to it.


Enter the number of scans to wait before attempting to reconnect to a device after a communications error has been detected.


Check if you want the port to be enabled when the project starts. If you clear this check box, the port will not be enabled when the project starts, and points will not be available for devices on the port.

Enable stale data

Check to keep the point available in most circumstances that would have made it unavailable. However the point value will be stale, meaning it is the last known value and may or may not have changed in the device.

More information

Modbus RTU port configuration.