GT-D is a high-precision and long-term stable temperature sensor (NTC) designed for installation in ventilation ducts. Placing the sensor in a duct is often a cost-effective solution that also provides some protection against damage.

The sensor is also available in a simpler version, GTN-D, designed to be used as an accessory for room-temperature control with the thermal actuator control unit SBTb.

Function

• GT-D: This temperature sensor is mounted in a housing with an insertion tube for duct installation. It converts the NTC sensor's resistance into a 0-10 V output signal within the temperature range of 12-43 ºC.
• GTN-D: The temperature sensor has the same housing as the GT-D but is a passive NTC sensor, meaning it does not convert the sensor signal into an active output signal.

Short Time Constant

The NTC resistor has a time constant of approximately 3 minutes in flowing air. When the temperature sensor is placed in the exhaust air duct, the temperature measurement can be affected if the ventilation flow is very low. However, this is not a problem when ventilation is increased during occupancy. A wall-mounted sensor has the disadvantage that the wall's temperature can affect the measurement and increase the time constant (up to 30 minutes for walls made of concrete or other inert materials).