In smaller sized greenhouses, a manual program opened and closed by hand could be installed. These work easiest when the screen materials is supported by a track system.
Start time – when in the morning will the screen system start operation
Stop period – when in the afternoon will the display system stop operation
Light level – at what light intensity will the screen be activated either to open up or close
Maximum/minimum temperature – what are the limitations of temperature rack drive for greenhouse china desired
Maximum/minimum humidity – What are the limitations of humidity desired
Gap positions – this pieces the percent open or close position under different conditions such as in early stages a winter early morning to lessen thermal shock or through the summer to supply better shading. The gap measures and speed of movement can be controlled in a few systems.
Time delay – under changeable climate this avoids frequent opening and closing
Wind speed – To lessen high temperature loss, the screen could be closed early below high wind speed conditions
Snow detection – this can open the display screen and turn on the heat when it begins to snow.
The typical system uses nylon monofilament or stainless cables to support the screen materials. The screen material can possibly rest along with the network of cables or be suspended by hooks from the cables. A gearmotor powers a drum or rack and pinion that movements the industry leading of the screen materials. Control is usually either with a manual change or electronic controller.
Based on the above, the grower must enter the following parameters in to the controller:
A climate station is required to provide outdoor light level, temperature, humidity, wind and rain or snow conditions.