In smaller greenhouses, a manual program opened and closed by hand could possibly be installed. These work easiest when the screen material is supported by a track system.
Start time – when in the morning will the display screen system start Rack Drive For Greenhouse operation
Stop time – when in the afternoon will the display system stop operation
Light level – in what light intensity will the screen be activated either to open up or close
Maximum/minimum temperature – what are the limitations of temperature desired
Maximum/minimum humidity – What exactly are the limitations of humidity desired
Gap positions – this models the percent open or close position under different conditions such as early on a winter morning to reduce thermal shock or through the summer to supply better shading. The gap guidelines and speed of motion can be controlled in some systems.
Time delay – under changeable weather conditions this avoids frequent starting and closing
Wind speed – To lessen temperature loss, the screen could be closed early under high wind speed conditions
Snow detection – this may open the display screen and turn on the heat when it starts to snow.
The typical system uses nylon monofilament or stainless steel cables to support the screen materials. The screen material can either rest on top of the network of cables or end up being suspended by hooks from the cables. A gearmotor 
powers a drum or rack and pinion that moves the industry leading of the screen material. Control is definitely either with a manual change or electronic controller.
Based on the over, the grower is required to enter the next parameters in to the controller:
A climate station is required to provide outdoor light level, temperature, humidity, wind and rain or snow conditions.
