9 of 48 3.1.3 Humidity Probe Reading (Optional) The instrument has the optional facility to use a humidity probe (specified at the time of manufacture. This allows the instrument to read and display humidity readings from an optional probe. When a humidity probe is fitted, the display will change automatically to show the current reading and a humidity probe icon will be displayed. The Scroll keys on the instrument panel are used to switch between the reading screens. The humidity kit comprises of: Humidity lead Humidity sensor Connection of the Humidity Sensor: Plug the humidity sensor onto the mating connector of the transmitter or connection cable. Make sure that the catches are aligned correctly. Tighten the knurled nut by hand. Note: The humidity sensor can take 30 minutes to stabilise and special handling is required for optimum performance and stability. Please refer to the instruction leaflet included with the humidity sensor packaging for the Humidity Standards.