The Multiple Hydrozone System, both wired (MHS) and wireless (W-MHS), works with your existing AC irrigation controller to eliminate programmed irrigations when plants have adequate soil moisture. It makes decisions to open or close the valve common wire or signals the controller, based on several criteria:
- valve program from irrigation controller
- soil moisture status of representative location
- operation of manual override
- allowed watering window
These parameters are set upon installation. Programming and operation of the system is done using the keypad and display on the MHS unit. Besides managing the soil moisture, the system will log data regarding system performance for a truly unique level of irrigation analysis and management.
Field Node is solar powered and shipped uncharged. Expose to sunlight for 1 to 2 hours.
When using the wireless system, Field Nodes are placed at representative locations around the property where soil moisture sensors will be located. They send data back to the W-MHS unit which is connected to your irrigation controller. The Field Nodes must be within “radio line of sight” (up to 1500 ft., 457 m) of the Base Node at or near the W-MHS unit location. Field Nodes must be installed so that the solar panel (built into every Field Node) receives adequate sunlight, ideally facing south (in the Northern Hemisphere). Each Field Node can read four WATERMARK sensors, thus allowing for measurements of two different Hydrozones, or groups of valves with similar watering demands. A total of eight Hydrozones can be managed with this system.
Field Nodes communicate with a Base Node located at or near the W-MHS unit via radio. Each node must be able to “see” the Base Node to provide adequate communication. This is what is meant by “radio line of sight” and is more than just a straight line between antennas; the longer the range the broader the signal and thus more interference that can be anticipated.
Range is improved by well planned installation height and node placement; 10 to 12 ft. (3 m) above ground is good for most applications. The Field Nodes are powered solely by the solar panel and no battery replacement is required. The Base Node is powered from the W-MHS unit panel and is wired as shown in the diagram on page 10 .
The Base Node can be installed up to 50 ft. (15 m) away from the W-MHS unit to provide better line of sight to the Field Nodes. In many cases an installation of the Base Node on a rooftop is best, especially if Field Nodes are on multiple sides of structures. The purchase of an auxiliary cable will be required if the Base Node is to be mounted away from the W-MHS unit. The W-MHS unit should be installed adjacent to the irrigation controller. Wires need to be run between the two units.
With large commercial landscapes, the variety of watering demands is often too diverse to be adequately judged by a single sensor location. For such applications, this control product provides the flexibility to independently control any number of valves- watering plants with similar watering demands (“Hydrozones”)- separately. Up to eight independent moisture zones can be created per 24VAC controller, to control up to 48 station valves.
This product is available in two versions: a “wired” version with up to 8 sensors wired to the MHS unit, and a “wireless” version using 2.4GHz solar powered radio nodes to transmit soil moisture readings to the MHS unit.
Our Landscape Design Guide demonstrates how all the WATERMARK soil moisture control products can be specified when designing systems.