In smaller greenhouses, a manual program opened and closed yourself could be installed. These work easiest when the screen material is backed by a monitor system.
Start time – when each morning will the screen system start operation
Stop period – when in the afternoon will the screen system stop operation
Light level – at what light intensity will the screen be activated either to open or close
Maximum/minimum temperature – what exactly are the limits of temperature desired
Maximum/minimum humidity – What are the limits of humidity desired
Gap positions – this units the percent open or close placement under different conditions such as in early stages a winter early morning to reduce thermal shock or during the rack drive for greenhouse china summer to provide better 
shading. The gap measures and speed of motion can be controlled in a few systems.
Time delay – below changeable climate this avoids frequent starting and closing
Wind speed – To reduce temperature loss, the screen can be closed early under high wind speed conditions
Snow detection – this can open the display screen and turn on heat when it begins to snow.
The typical system uses nylon monofilament or stainless steel cables to support the screen material. The screen material can possibly rest along with 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 materials. Control is certainly either with a manual switch 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.