In smaller greenhouses, a rack drive for greenhouse china manual program opened and closed yourself could possibly be installed. These work simplest when the screen materials is supported by a monitor system.
Start time – when each morning will the display screen system start operation
Stop time – when in the afternoon will the display screen system stop operation
Light level – at what light strength 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 exactly are the limits of humidity desired
Gap positions – this units the percent open up or close placement under different conditions such as in early stages a winter morning to lessen thermal shock or during the summer to supply better shading. The gap methods and speed of motion can be controlled in some systems.
Time delay – below changeable climate this avoids frequent starting and closing
Wind speed – To lessen heat loss, the screen can be closed early under high wind speed conditions
Snow detection – this can open the display and turn on heat when it starts to snow.
The standard system uses nylon monofilament or stainless cables to aid the screen materials. The screen material can either rest on top of the network of cables or become 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 certainly either with a manual change or electronic 
controller.
Based on the over, the grower must enter the next parameters in to the controller:
A weather station is required to provide outdoor light level, temperature, humidity, wind and rain or snow conditions.