humidifier

B. Darnton humidifier A "mist propagation unit" maintains plant cuttings and newly sown seeds in a moist environment until rooting is effected or the seeds have germinated. Generally, the equipment consists of a spray head which is supplied with water via a solenoid valve which is in turn controlled by a relay. Now we come to the electronics. The relay is activated by an "electric leaf". When the exposed electrodes of this device become moist, the relay is deactivated and the water valve closes. As soon as the electrodes dry out the solenoid is again opened. In the glasshouse situation it is the electric leaf that causes most of the problems inte traditional unit. The electrodes become coated with carbonates as the tap water evaporates (causing insulation) and any metallic contacts and wires suffer from the effects of electrolysis and become corroded. A new system which is not exposed to the hazards of water, yet which responds to the transpiration requirements of the plant would ...