Hunter Technical Support Document

In most installations, the Mini-Clik acts as a switch breaking the circuit to solenoid valves of an irrigation system when it rains. This allows the timer to advance as scheduled, but keeps the valves from opening allowing water to flow. Once the Mini-Clik has dried, the switch closes again to allow for normal operation.

Model Mini-Clik-HV(110VAC): This rain sensor unit is designed to be used with automatic irrigation systems of two principle designs:

1) single-station electrical timers that switch power to a pump, either directly or through a relay 

2) single-station electrical timers that switch power to a solenoid valve

Mounting

Standard Model: Using the screws provided, mount the Mini-Clik on any surface where it will be exposed to unobstructed rainfall, but not in the path of sprinkler spray. The switch-housing portion must be upright (as pictured), but the swivel-bracket can be moved for mounting on any angled surface. Loosen the locknut and screw before swiveling bracket, and then re-tighten.

For the Conduit Model Mini-Clik-C: The conduit acts as the mounting support for the unit. Therefore, place and mount the conduit to allow for the desired sensor location as described in the main instructions for the standard model. Be sure to support the conduit sufficiently along its various lengths.

For the High-Voltage Model Mini-Clik-HV: The mounting of this unit is primarily made by screwing the fitting end into the threaded holes of covers to rectangular junction boxes (for outdoor use) or the covers of round junction boxes commonly used for outdoor spotlights. Locate the junction box so that with the Mini-Clik attached, unobstructed rainfall will hit the outermost sensing end of the unit. If a longer reach is needed, the “Carlon” flexible conduit piece can be substituted with a slightly longer piece (up to 8ft/2.44m length with no support or up to 11ft//3.35m with support).

Helpful hints for mounting:

1. When looking for a suitable location such as on the side of a building or post, the closer the Mini-Clik is to the controller, the shorter the wire run will be. This will also minimize the chance for wire breaks.
2. The ideal location for mounting is not always the most practical location. In the case where a compromise must exist (such as low location on a side wall rather than the preferred high location), note that the Mini-Clik will still work as it will always receive some rainfall – it just will not be as accurate in its gauging as it could be.
3. As described in the “Operation” section of this manual, “reset rate” refers to the amount of time it takes the Mini-Clik to dry out sufficiently for the sprinkler system to be allowed to come back on. The mounting location will affect this rate and should be taken into consideration should extreme conditions exist. For example, mounting the Mini-Clik on a very sunny, southern end of a building may cause the Mini-Clik to dry out sooner than desired. Similarly, mounting on the northern end of a building with constant shade may keep the Mini-Clik from drying soon enough.

Once the Mini-Clik is mounted, run the wire to the controller, and fasten it every few feet with wire clips or staples for best results. If an extension to the wire provided is needed, use the following table to determine the minimum wire gauge needed:

Hunter SRC

The Mini-Clik connects directly to the SRC. This allows you to easily override the sensor by using the RUN (BYPASS SENSOR) position on the dial.

1. Connect one wire to the RS terminal and other to the C terminal (See Figure 1).
2. Connect the valve common to the RS terminal.

X-Core, Pro-C, ICC and I-Core

The Mini-Clik connects directly to the X-Core, Pro-C, ICC and I-Core. This allows you to easily override the sensor by using the Sensor switch on the front panel.

1. Remove the jumper from the two “SEN” terminals.
2. Connect one wire from the sensor to one wire terminal labeled "SEN", then connect the other sensor wire to the other wire terminal labeled "SEN".(Figure 2)

Other Controllers

The two most common situations are shown below.

24 Volt Solenoid Valves Only (No booster pump) (See Figure 3)

• With the two wires from the Mini-Clik at the controller, locate the “common wire" of the solenoid valves. If it is connected to the common terminal on the controller, disconnect it. Attach one wire of the Mini-Clik to the “common” terminal (usually marked “C”) on the controller. Attach the other wire of the Mini-Clik to the common wire leading to the valves.(Figure 3)

24 Volt Solenoid Valves (with Booster Pump) (See Figure 4)

• Locate the "common wire" to the solenoid valves and the common wire leading to the coil of the relay that starts the pump. If these two wires are connected to the “common” terminal on the controller, disconnect both of them. Twist together these two wires along with one wire from the Mini-Clik, and secure with a wire nut. Attach the other wire of the Mini-Clik to the “common” terminal on the controller. Note: The pump circuit output must be 24 Volts in this situation. Do not proceed if 110V.

Mini-Clik-HV

The two taped and stripped wires are the ones to be used when following these accompanying diagrams. The third wire should be terminated with a wire nut. (See Figures 5 and 6)

The wiring for an internal or external relay is the same: the Mini-Clik breaks the circuit to the coil of the relay only.

In instances where the timer is controlling a pump, the relay may be inside the timer.

Adjustments and Operation

The Mini-Clik can keep the irrigation system from starting or continuing after rainfall quantities of 1/8", 1/4", 1/2", 3/4"  or 1" (3.17, 6.35, 12.7, 19.05mm). To adjust it to the desired shut-off quantity, rotate the cap on the switch housing so that the pins are located in the proper slots (see Figure 7). Do not forcibly twist the cap as this might break the pins.

The time that it takes the Mini-Clik to reset for normal sprinkler operation after the rain has stopped is determined by weather conditions (wind, sunlight, humidity, etc.) These conditions will determine how fast the hygroscopic discs dry out, and since the turf is also experiencing the same conditions, their respective drying rates will roughly parallel each other. So when the turf needs more water, the Mini-Clik is already reset to allow the sprinkler system to go at the next scheduled cycle.

There is an adjustment capability on the Mini-Clik that will slow down the reset rate. By turning the “vent ring” (see Figure 7) to completely or partially cover the ventilation holes, the hygroscopic discs will dry more slowly. This adjustment can compensate for an “overly sunny” installation location, or peculiar soil conditions.