Rain Bird RSD-BEX Rain Sensor User Manual

1. Introduction

This manual provides detailed instructions for the installation, operation, and maintenance of the Rain Bird RSD-BEX Rain Sensor. The RSD-BEX is designed to automatically measure precipitation and prevent irrigation systems from watering during rainy conditions, thereby conserving water and extending the life of your irrigation system. It is compatible with 24VAC residential and commercial irrigation controllers.

2. Product Overview

The Rain Bird RSD-BEX Rain Sensor features a durable, UV-resistant polymer body and an aluminum latching bracket for secure mounting. It includes a 25-foot extension wire for flexible installation.

Figure 2.1: Rain Bird RSD-BEX Rain Sensor with its aluminum mounting bracket and attached extension wire. The sensor unit is visible on the left, connected to the bracket, with the gray wire extending to the right.

Key Features:

• Multiple Rainfall Settings: Adjustable from 1/8" to 3/4" (5-20mm) with a twist dial.
• Adjustable Vent Ring: Controls the drying time of the hydroscopic discs.
• Durable Construction: High-grade, UV-resistant polymer body and rugged aluminum 5-inch bracket.
• Extended Wire: 25 feet (7.6 m) of UV-resistant extension wire for easy connection.
• Compatibility: Works with all popular 24VAC controllers and pump start relays.

Figure 2.2: A close-up view of the Rain Bird RSD-BEX Rain Sensor unit. The label "Rain Bird Corp. 24 VAC RSD-BEX Rain Sensor" is clearly visible, along with regulatory marks (UL, cUL, CE, EAC) and "Made in Mexico".

3. Specifications

4. Setup and Installation

Proper installation is crucial for the optimal performance of your Rain Bird RSD-BEX Rain Sensor. Ensure the sensor is installed in an area that accurately reflects rainfall and is not obstructed.

4.1 Mounting Location

• Choose a location that is exposed to unobstructed rainfall, away from eaves, trees, or overhangs that might block rain.
• The sensor should be mounted vertically, ensuring the top of the sensor is level.
• Consider accessibility for future adjustments or maintenance.

Figure 4.1: The Rain Bird RSD-BEX Rain Sensor attached to its aluminum bracket, ready for mounting. The sensor's top cap is visible, designed to collect rainfall.

4.2 Wiring Instructions

The RSD-BEX sensor connects to your 24VAC irrigation controller. It comes with 25 feet of two-conductor wire.

1. Locate the sensor terminals on your irrigation controller. These are typically labeled "Sensor" or "Rain Sensor." Consult your controller's manual for specific wiring diagrams.
2. Connect one wire from the RSD-BEX sensor to one of the sensor terminals on the controller.
3. Connect the second wire from the RSD-BEX sensor to the other sensor terminal. The polarity typically does not matter for rain sensors.
4. Ensure all connections are secure and protected from moisture.

Figure 4.2: The 25-foot (7.6m) UV-resistant two-conductor extension wire provided with the Rain Bird RSD-BEX Rain Sensor, coiled for packaging. This wire facilitates flexible placement of the sensor relative to the irrigation controller.

Note: The RSD-BEX is designed for use with Rain Bird electronics technology. It is not designed for other brand applications. It is suitable to switch up to ten 24VAC, 7VA solenoid valves per station, plus one master valve.

5. Operation

The Rain Bird RSD-BEX Rain Sensor operates by detecting rainfall and interrupting the irrigation cycle when a preset amount of rain has fallen.

5.1 Adjusting Rainfall Settings

The sensor features a twist dial on the top to set the desired rainfall accumulation before irrigation is suspended. Settings range from 1/8" to 3/4" (5-20mm).

1. Locate the twist dial on the top of the sensor unit.
2. Rotate the dial to align the indicator with your desired rainfall setting. For example, select 1/4" if you want irrigation to stop after 1/4 inch of rain has fallen.
3. The sensor will automatically reset once the internal hydroscopic discs dry out.

5.2 Adjusting Drying Time

An adjustable vent ring allows you to control how quickly the internal hydroscopic discs dry out, which in turn affects how soon the irrigation system can resume operation after rain has stopped.

• To allow for faster drying, open the vent ring.
• To slow down drying, close the vent ring.
• Adjust this setting based on your local climate and soil conditions.

6. Maintenance

The Rain Bird RSD-BEX Rain Sensor is designed for minimal maintenance. However, periodic checks can ensure its continued reliability.

• Clear Debris: Periodically inspect the sensor's top cap and vent ring for any leaves, dirt, or other debris that might obstruct rainfall or airflow. Gently remove any obstructions.
• Check Wiring: Ensure the wiring connections remain secure and free from damage or corrosion.
• Verify Operation: During dry periods, you can manually test the sensor by pouring a small amount of water into the top cap to simulate rainfall. Observe if the irrigation system is suspended.

7. Troubleshooting

8. Warranty and Support

For warranty information and technical support, please refer to the official Fluidra or Rain Bird website, or contact their customer service directly. Keep your purchase receipt as proof of purchase.

Manufacturer: Rain Bird

Brand: Fluidra