Siemens 186-0089 HUMIDITY TRANSMITTER, DUCT, DA, 1-PIPE, BIMETAL TEMPERATURE COMPENSATIONSiemens 186 0089 This 186 Duct Humidity Transmitter is an one pipe, direct acting pneumatic instruments that sense space humidity and transmit a 3 to 15 psi pneumatic signal to a remote receiver gauge and or receiver controller to read percent relative humidity. This transmitter has a 20 to 80 percent relative humidity, an outlet pressure of 3 to 15 psi, and is to be mounted vertically at least 6" high and 6. 5" deep. The transmitter should be used in