In smaller greenhouses, a manual system opened and closed yourself could possibly 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 period – when in the afternoon will the display screen system stop operation
Light level – in what light strength will the screen end up being 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 sets the percent open up or close placement under different conditions such as early on a winter morning to lessen thermal shock or through the summer to provide better shading. The gap steps and speed of motion can be controlled in some systems.
Time delay – under changeable Rack Drive For Greenhouse weather conditions this avoids frequent opening and closing
Wind speed – To lessen heat loss, the screen can be closed early below high wind speed conditions
Snow detection – this can open the display and turn on heat when it begins 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 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 change or electronic controller.
Based on the over, the grower must enter the next parameters in to the controller:
A weather station is needed to provide outdoor light level, temperature, humidity, wind and rain or snow conditions.