﻿This parameter determines which sensor is used for temperature measurement.

*Wired sensor (input 3)*: The temperature value is determined exclusively by the NTC temperature sensor connected to input 3. With this configuration, temperature measurement starts a few seconds after a device reset (bus voltage return, ETS programming operation).

*Wired sensor (input 3) and external sensor (object)*: With this setting, two temperature sensors are combined. The temperature is determined by the NTC temperature sensor connected to input 3 and also by a temperature value received from the KNX. This external sensor is coupled via the 2-byte object "External sensor" and can be a KNX room thermostat or a controller extension with temperature detection. A few seconds after a device reset (bus voltage return, ETS programming operation), the temperature measurement starts. If no temperature value has yet been received via the "External sensor" object when evaluating an external temperature sensor, only the value formed by the internal sensor is processed.
