In smaller greenhouses, a manual program opened and closed by hand could Motor Gearboxes For Greenhouse possibly be installed. These work easiest when the screen material is supported by a track system.
Start time – when each morning will the display system start operation
Stop time – when in the afternoon will the screen 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 are the limits of humidity desired
Gap positions – this pieces the percent open up or close placement under different conditions such as in early stages a winter early morning to reduce thermal shock or through the summer to provide better shading. The gap actions and speed of movement can be controlled in some systems.
Time delay – under changeable climate this avoids frequent opening 
and closing
Wind speed – To reduce warmth loss, the screen could be closed early under high wind speed conditions
Snow detection – this may open the screen and turn on heat when it starts to snow.
The standard system uses nylon monofilament or stainless steel cables to support the screen materials. 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 movements the industry leading of the screen materials. Control can be 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 climate station is required to provide outdoor light level, temperature, humidity, wind and rain or snow conditions.