In smaller sized greenhouses, a manual program opened and closed by hand could be installed. These work easiest when the screen material is supported by a monitor system.
Start time – when in the morning will the screen system start operation
Stop time – when in the afternoon will the display system stop operation
Light level – in what light intensity will the screen be activated either to open or close
Maximum/minimum temperature – what are the limits of temperature desired
Maximum/minimum humidity – What exactly are the limits of humidity desired
Gap positions – this models the percent open or close position under different conditions such as early on a winter early morning to Rack Drive For Greenhouse lessen thermal shock or through the summer to supply better shading. The gap techniques and speed of motion can be controlled in a few systems.
Time delay – below changeable weather conditions this avoids frequent opening and closing
Wind speed – To reduce high temperature loss, the screen could be closed early below 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 cables to aid the screen material. The screen material can possibly rest along with the network of cables or be suspended by hooks from the cables. A gearmotor powers a drum or rack and pinion that moves the industry leading of the screen materials. Control can be either with a manual switch or electronic controller.
Based on the over, the grower must enter the next parameters in to the controller:
A weather station is required to provide outdoor light level, temperature, humidity, wind and rain or snow conditions.