In smaller sized greenhouses, a manual program opened and closed by hand could possibly be installed. These work easiest when the screen materials is supported by a monitor system.
Start time – when each morning will the display system start operation
Stop period – when in the afternoon will the screen system stop operation
Light level – at what light intensity will the screen become activated either to open up 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 models the percent open up or close position under different conditions such as in early stages a winter morning to lessen thermal shock or during the summer to provide better shading. The gap techniques and speed of Motor Gearboxes For Greenhouse movement can be controlled in some systems.
Time delay – under changeable weather conditions 
this avoids frequent starting and closing
Wind speed – To lessen high temperature loss, the screen can be closed early below 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 aid the screen materials. The screen material can either 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 techniques the industry leading of the screen materials. Control is usually either with a manual switch or electronic controller.
Based on the above, the grower is required to enter the next parameters into the controller:
A weather station is required to provide outdoor light level, temperature, humidity, wind and rain or snow conditions.