Inovance Modbus TCP FAQ
Unable to Read Tag Value, Error Code 3002
- Turn on DEBUG logs, check the logs, data flow, and whether the device has responded with correct data (if multiple upstream devices are collecting data from the same serial device, exceptions may occur).
- Check if the address is correct.
- Check if the connection is valid. Use the telnet command to detect if there are any abnormalities in the link.
- The device supports the Modbus RTU protocol, not Modbus TCP. Try using the Modbus RTU plugin.
Tag value Invalid, Error Code 3008
- The device is offline and the data cannot be updated.
- The device does not respond within a certain period of time.
- The device supports the Modbus RTU protocol, not Modbus TCP. Try using the Modbus RTU plugin.
Tag Value Read does not Match Expectations
- Incorrect data type.
- Incorrect byte order.
- Presence of multiple upstream masters collecting data results in data corruption.
- The device actively uploads data, but the standard Modbus only supports requesting and then responding with corresponding data.
- The device supports Modbus RTU protocol instead of Modbus TCP. Try using the Modbus RTU plugin.
Importing Tags Failed
- Incorrect selection of data type.
- Tag address exceeds the specified range.
- Error in the point address format; X and Y area addresses use octal notation.