Irrigation controller Water Pro VPD

The WATER PRO is a “state of the art” VPD misting and irrigation control system. Each station may be individually programmed for either misting, or irrigation. The Water Pro has many on board features that you can also use to customize it for your particular needs. 12 zones, expandable to 24 zones with expansion unit A 2nd VPD sensor can be added Can be connected to a remote PC and used with the optional Growlink software for sensor data logging and remote control operation Crop aging adjustments End of schedule alarm Night watering disable functions 24V transformer and power cord included, 24VAC output 1 yr warranty UNDERSTANDING VAPOR PRESSURE DEFICIT (VPD) WATER PRO There has been a significant amount of study by a number of environmental and watering experts concerning this basic principle of using VPD to determine when plants need water. Unlike other methods used to determine watering, using VPD looks at the entire environmental conditions surrounding the plant. The VPD Sensor that we use measures Temperature of the Air, Humidity of the Air, and the Temperature of the Leaf of the plant. With these instantaneous sensor values we can determine the VPD of the plants in the greenhouse at regular intervals (every 10 seconds). As the environmental conditions change so does the VPD. By adding the VPD’s together we work our way toward a target where we know the plant must have water. After we water the plant the process starts all over again Just what is Vapor Pressure Deficit (VPD) and how does it relate to plants? Not really a difficult question to answer. To understand VPD we must understand the following: How water moves through a plant. A plant’s structure.