There are 3 modes of irrigation; schedule, local, and global.
In the schedule mode you set a schedule for when the node should irrigate. This schedule is also used as a basis for the other modes.
In local control mode if the moisture is less than a setpoint value and the schedule is enabled at that time then it will irrigate. The node takes a reading every 1 minute and averages together 5 minutes of readings. If that average is less than the setpoint than an irrigation cycle begins. Each irrigation cycle is 5 minutes long.
For local control all of the sensors used must be the same. EC-5, 10-HS, 5TE, 5TM, and GS-3 moisture sensors are supported.
Global control works in one of two ways. In model based tools the model will directly command an irrigation event to occur, this may or may not use the schedule. In standard growing tools, the operation is very similar to local control where a growing tool output value and a setpoint are set to control irrigation in conjunction with the schedule. One key difference between this global control and local control is the ability to use sensors from other nodes and computed data products to control irrigation.
There are 3 parameters that control what happens in an irrigation cycle (this is the pulse types).
Pulse length – How long to water
Time between pulses – How long to wait between pulses
Number of pulses – How many pulses to do
This total time must be less than or equal to 5 minutes so (pulse length + time between pulses) * number of pulses <= 5 minutes. One of the reasons for this strategy is allow for gaps between irrigation events. This lets the water travel from the surface to the sensors for better irrigation control. [testimonial_rotator id=143]