Why is a Eureka Sonde Not Detecting?
If a Eureka Water Quality Sonde is not detecting on a NexSens X-Series data logger after following the integration guide, here are a few common reasons that should be reviewed.

What are the NexSens 8-Pin UW Connector signal connections?
If connecting a NexSens UW8 connector to an external device that is not an X-Series data logger, below is the pinout schematic of the NexSens UW8 connector, along with the pins associated with the communication, ground, and power signals for RS-232 sensors.