In smaller greenhouses, a manual system opened and closed by hand could be installed. These work simplest when the screen material is backed by a monitor system.

Start time - when each morning will the screen system start operation
Stop time - when in the afternoon will the screen system stop operation
Light level - in what light intensity will the screen end up being activated either to open or close
Maximum/minimum Rack Drive For Greenhouse temperature - what exactly are the limitations of temperature desired
Maximum/minimum humidity - What exactly are the limitations of humidity desired
Gap positions - this sets the percent open or close placement under different circumstances such as in early stages a winter morning to reduce thermal shock or through the summer to supply better shading. The gap methods and speed of motion can be controlled in a few systems.
Time delay - below changeable climate this avoids frequent opening and closing
Wind speed - To lessen temperature loss, the screen could be closed early below high wind speed conditions
Snow detection - this can open the screen and turn on the heat when it begins to snow.
The standard system uses nylon monofilament or stainless steel cables to support the screen materials. The screen material can possibly 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 leading edge of the screen materials. Control is definitely either with a manual switch or electronic controller.

Based on the above, the grower is required to enter the following parameters into the controller:

A climate station is needed to provide outdoor light level, temperature, humidity, wind and rain or snow conditions.