Relative Humidity and RH/Temperature Transmitters

Use these transmitters to monitor your relative humidity conditions. We offer transmitters to monitor either relative humidity or both relative humidity and temperature. Choose from several mounting styles to handle your various monitoring locations including outdoor sites.

Transmitters convert the physical data into a measurable 4-20 mA output signal that can be transmitted to a compatible receiving device. (Note: A power supply is required to produce the 4-20 mA output signal.) Use the RH transmitters with receiving devices that accept a 4-20 mA input, such as panel meters, recorders, or controllers.


Two-Wire External Loop Power System
Two-wire external loop power system

The power supply for a two-wire transmitter can be a separate source. The diagram at the right shows the recommended wiring for a two-wire transmitter with an external loop power system.


Two-Wire Internal Loop Power System
Two-wire internal loop power system

The power supply for a two-wire transmitter can also be provided by the receiving instrument if the receiving instrument has a built-in power supply. The diagram above shows the recommended wiring for a two-wire transmitter with an internal loop power system.


Four-Wire Power System
Four-wire power system

For a four-wire transmitter, the power supply and the receiving device are not wired in a loop configuration. See the diagram at the right for the recommended wiring.