Honeywell channel temperature sensor
The type of temperature sensors used to measure the temperature of air ducts are known as duct temperature sensors .
The basis for measuring the temperature inside these sensors is the use of PT100 resistors.
As you know, these types of sensors are classified as positive thermal coefficient (PTC) resistors.
In other words, as the temperature increases, the resistance of the sensor also increases. The PT100 sensors, which are made of platinum, show a resistance of 100 ohms at zero degrees Celsius, and according to the American IEC standard, its resistance increases by 0.385 ohms with each degree Celsius increase.
Duct temperature and humidity sensor
Therefore, the metal resistance is expected to be 138.5 ohms at 100 ° C.
As it is known, changes in resistance will indicate the temperature of the fluid, these types of sensors are used to measure the range -50 to 250 ° C.
NTC sensors can be used to improve the measurement accuracy. These sensors are known as negative heat coefficient.
In these sensors, increasing the temperature will reduce the resistance of the metal.