Relativity humidity is the amount of moisture in the air as a percentage of the maximum amount possible at a given temperature. Relative humidity is given in units of %RH. It is important to measure and control humidity within greenhouses and indoor hydroponic gardens. As part of photosynthesis plants transpire water through pores in their leaves, called stomata, into the air. This process also keeps plants cool, similar to sweat, and prevents them from overheating and drying out. Having the correct humidity helps plants to grow faster. It also prevents the growth of mold and pests.
Below are the most common products used for measuring relative humidity.
A transmitter with 4-20 mA signals for relative humidity and temperature is available. This transmitter is for on-site, continuous monitoring of relative humidity and temperature in critical or controlled environments. The analog output can be sent to chart recorders or other recording devices.
The following category is for the replacement probes used with Hanna portable thermo-hygrometers.
AAccessories for relative humidity meters include shockproof rubber boots for the portable thermo-hygrometers and a calibration chamber for use with the transmitter.