In smaller sized greenhouses, a manual program opened and closed by hand could 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 rack drive for greenhouse china operation
Stop period – when in the afternoon will the display 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 limitations of temperature desired
Maximum/minimum humidity – What are the limitations of humidity desired
Gap positions – this models the percent open up or close position under different circumstances such as in early stages a winter early morning to lessen thermal shock or during the summer to provide better shading. The gap measures and speed of movement can be controlled in some systems.
Time delay – under changeable climate this avoids frequent starting and closing
Wind speed – To reduce high temperature loss, the screen could be closed early below high wind speed conditions
Snow detection – this can open the display screen and turn on the 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 become suspended by hooks from the cables. A gearmotor powers a drum or rack and pinion that techniques the industry leading of the screen material. Control can be either with a manual switch or electronic controller.
Based on the over, the grower must enter the next parameters into the controller:
A weather station is needed to provide outdoor light level, temperature, humidity, wind and rain or snow conditions.