Sonde DS18B20 waterproof 1-Wire

The DS18B20 probe is the reference for robust, simple temperature measurement: 1-Wire bus, unique per-sensor addressing, and above all the waterproof cabled version that you plunge directly into a tank, a bath or against a motor housing. You chain dozens of probes on two wires, which radically simplifies the wiring of a thermal map.

Limits: the accuracy (±0,5 °C over −10/+85 °C) and the +125 °C ceiling confine it to lukewarm-to-moderately-hot processes. For a furnace, a hearth or any point above 125 °C, the type-K thermocouple + MAX31855 is mandatory. 1-Wire is slow: it is not a fast-dynamics sensor, but one for tracking a thermal regime.