The TrueRH product line delivers +/-2% and +/-3% Relative Humidity (RH) Sensing Products in a full variety of packages. The humidity sensor's All-Polymer construction increases resistance to corrosion in HVAC (Heating, Ventilating, and Air Conditioning) environments. HE-67xx Elements are products whose output signal is 0 to 5 VDC for humidity Indication. The HE-67xx Series sensors combine humidity and temperature sensing in an all-plastic enclosure used inside ducts and economizer rooftop systems. These models are available with a nickel or one of two thermistor temperature sensors. The thermistor temperature sensors have a negative temperature coefficient, and a reference resistance of 2.2k ohms or 10.0k ohms. The nickel temperature sensor has a reference resistance of 1.0k ohms. These units can be powered with 14 to 30 VDC or 20 to 30 VAC and feature a 0 to 5 VDC output. Protective membrane protects sensors from contamination. Quick-mount, 2-screw installation reduces installation time. Compact enclosure for mounting inside ducts?designed for rooftop unit applications and retrofits; enables surface mount installation.