Flow Manager runs simultaneous stations to reach a programmable flow rate target. It allows the controller to decide which stations to run, to keep total flow as close to the pipe design capacity as possible, and shorten the overall watering time.
Flow Manager does not require a flow sensor, but it must have station flow values to work with. If flow learning via a sensor is not available, approximate values may be entered manually.
Flow Manager does require one or more Flow Zones, and requires stations to be attached to the Flow Zones in order to function. Flow Manager and Flow Monitor can also work at the same time, and use much of the same information in different ways.
Flow Manager requires the following information to operate correctly:
- Set up Flow Zones and set Flow Targets (Flow menu, Flow Zones)
- Attach stations to Flow Zones (Stations, Station Setup)
- Learn or enter station flow rates (Stations, Station Setup)
- Set Controller Program Limits, (Stations, Station Limits menu), if desired.
Dial to the Flow menu and select Flow Zones if they have not already been created. The Flow Zone defines a section of pipe and a group of stations attached to that pipe, which is managed as a hydraulic unit.
For Flow Manager, it is only necessary to Enable Flow Management and set the Flow Target. Check the box for Manage Flow.
The Flow Target box is used to set the flow rate desired for the Flow Zone throughout irrigation. Enter the desired rate of flow that is best for the mainline pipe diameter (recommended at 5 feet per second or 1.5 meters per second) or a preference based on other factors.
This is the only setting necessary at the Flow Zone menu for the Flow Manager function. Flow Manager will try to run enough simultaneous stations to stay at or near this rate of flow whenever there are programs available to run.
Flow Manager requires:
- The station’s Flow Zone assignment
- The Flow Priority (checked or not checked)
- The station Flow Rate.
This tells the controller which Flow Zone the station belongs to.
If there are multiple Flow Zones (collections of stations attached to the same mainline), it is possible to have a different Flow Target in each one.
It is also possible to have Flow Zones that run without Flow Manager, simultaneously with Flow Zones that are being managed.
The priority setting helps the controller decide which stations to run sooner to achieve Flow Targets. Stations with the Priority box checked will be considered first, so that less critical stations can occur later in the irrigation.
If the system is equipped with a flow sensor, it is best to use the “Learn Flow” function to let the controller fill these values in.
If the system does not have a flow sensor, look up or calculate reasonable flow values for each station, and enter manually for each station.
Note that Copy and Paste do not work with flow rates. They only copy the upper half of the screen, including P/MV and Flow Zone assignments.
Dial to Stations, Station Limits to review or change the number of stations that are allowed to run at once.
It is not necessary to change Station Limits for Flow Manager to operate, but it is possible. These settings can be used to customize the results of flow management.
Maximum Simultaneous Stations sets a hard limit on the number of stations the controller can run at once, regardless of Flow Manager or other settings. The ACC2 Decoder controller can run approximately 20 Hunter solenoids at once on a single output module, including P/MV outputs. The decoder controller can run up to 30 stations at once, provided they are spread over multiple decoder output modules, with not more than 20 active on each output module.
This may vary according to other factors, and there may be other reasons to limit the total number of simultaneous stations.
Enter a Controller number that meets your needs if the default of eight is not desirable.
If Flow Manager is enabled, a maximum number of simultaneous stations per program can also be entered. This can be useful to force the controller to spread irrigation across multiple programs, for example.
Example: Program 1 runs turf zones, and Program 2 runs shrub zones. If they are both part of the same flow-managed Flow Zone, and you know the Flow Zone can run about six zones at once, you could set a limit of three on Program 1 and three on Program 2. The controller will still flow manage to your target flow, but could only run three in either program to get there.
If the Flow Target rates are well below the rates that the Controller and Program station limits would allow, the station limits will never be reached. The controller will decide which stations to run, and in what order.