for reliable humidity measurement
|
|
|
For over 150 years relative humidity (RH) has been measured using the principle of "wet" and "dry" bulb temperature measurement. This reliable and above all accurate system is widely used in greenhouse horticulture. The system works by using one "dry" and one "wet" temperature sensor. By measuring both temperatures the computer can very accurately calculate the humidity in the air. Due to the water on the " wet" bulb temperature sensor evaporating, water must continuously be fed to it from the reservoir. This is achieved using a wick that sucks up water relying on the principle of capillary action. High demands are placed on this wick. As it dries out, the climate computer will register RH which is too high and - quite wrongly - takes measures to eliminate this apparently high humidity by venting or possibly even raising the temperature. Apart from the fact that this is a considerable waste of energy, in reality, a RH develops that is too low, which may even result in crop damage. Hence the need for a wick that will continue working reliably for weeks at a time. The wick may dry out due to deterioration of its capillary capabilities. This may be caused by impurities in the measuring unit, such as limescale (which is why you should never use tapwater in the unit!), particles that are sucked in by the fan such as airborne dirt, dust and insects, but also by the growth of algae in the reservoir. Micro-organisms (bacteria and fungi) can also develop in the water and in the wick.
Aquanex has been on the market since 1992 and has been thoroughly tested. Using precision instruments, the Centre for Agrotechnology and Physics (TFDL) has determined that Aquanex does not affect the recorded RH value. Aquanex has been satisfactorily used at various research stations (e.g. at Horst and Aalsmeer).
"Measuring humidity is vitally important to growing a quality product, and that's where Aquanex comes in." -
Wim Grootscholten (see references)
|
||||
However,
using Aquanex Measuring Unit Fluid,
instead of demineralised water, the reservoir is 'automatically'
kept clean. The fluid counteracts the growth of algae, fungi and
bacteria. Impurities that enter the reservoir are broken down. Aquanex
Measuring Unit Fluid keeps the capillaries in the wick open
by expanding them very slowly. This prevents non soluble dust particles
from blocking the transport of the fluid.