Why is a T-Node FR Not Detecting?
The NexSens T-Node FR User Guide outlines the required process for integrating a T-Node FR temperature sensor or string with a NexSens X-Series data logger. If one or multiple nodes along the string fail to detect after following the guide, below is a list of common reasons.
Issues During T-Node FR Detection
- Issue #1: Two or multiple nodes (or other sensors using Modbus) have the same Modbus address.
- Explanation: NexSens X-Series data loggers can only detect a T-Node if it has a unique Modbus address assigned. If another sensor using the Modbus communication protocol has the same address, both sensors will respond simultaneously to commands. Thus, communication will be interrupted as the logger expects a specific response.
- Solution: Review and adjust the Modbus address for each sensor in their respective software. Follow the Change the Modbus Address of a T-Node FR article.
- Explanation: NexSens X-Series data loggers can only detect a T-Node if it has a unique Modbus address assigned. If another sensor using the Modbus communication protocol has the same address, both sensors will respond simultaneously to commands. Thus, communication will be interrupted as the logger expects a specific response.
- Issue #2: The nodes within the string are not addressed in increasing numerical order.
- Explanation: NexSens X-Series data loggers treat the complete string as a single sensor instead of each node as its own sensor. Thus, the first node should be the lowest address, and the last node on the string should be the highest. The internal script will begin with the first address and end when there is a break in the available addresses.
- Solution: Check or change the Modbus address of each thermistor in the string. Ensure to note the serial numbers associated with each address to put the string together in proper order.
- Explanation: NexSens X-Series data loggers treat the complete string as a single sensor instead of each node as its own sensor. Thus, the first node should be the lowest address, and the last node on the string should be the highest. The internal script will begin with the first address and end when there is a break in the available addresses.