The EE45 sensor specifically developed to detect surface humidity conditions and to provide a switched indication when surface humidity is approaching 90% RH, indicating that condensation is eminent. A large thermal mass built into the sensor ensures thermal equilibrium is achieved with whatever surface it is attached to. Often used to monitor condensation conditions for radiant cooling systems. Working Range: 10 to 100% RH, 0 to 122°F (0 to 50°C). Floating photocoupler output for <50 VDC and <10 mA DC.