Our relay is an “open circuit” electric switch that is used to connect high voltage (120/240 VAC) from a high voltage source to a pump or other high voltage circuit. The relay/switch is activated by connecting a 24 VAC source to the two blue wires on the relay coil.
Most controllers do not provide sufficient voltage or current to operate a 120 VAC or 240 VAC pump, so a Pump Start Relay is required for a Controller to operate a pump.
Space #
The Hydro-Rain Pump Start Relay should be mounted at least 5 feet away from the Controller. The Controller should be mounted at least 12 feet away from the pump.
NOTE: Pumps and relays generate an electromagnetic field that can interfere with electronic devices. The Pump Start Relay is designed differently than the Controller, thus they have different recommended distances from the pump and each other. These recommended distances are the minimum recommended distance, you can place them father apart if needed.
Mounting #
The relay can be mounted outdoors. To prevent overheating, do not mount the relay in direct sunlight.
Please refer to your Controller instructions to determine if it can be mounted indoors or outdoors. To prevent overheating, do not mount the Controller in direct sunlight.
Wiring #
The Pump Start Relay can be used to operate a 120 VAC or 240 VAC pump as long as the current does not exceed 25 amps (about 2 Horsepower). If a larger pump is connected to 120 VAC instead of 240 VAC it could pull more than the 25-amp rating of the Pump Start Relay. This could cause the relay to overheat and cause physical damage to the relay.
The two blue wires are labeled 24 VAC. One Wire will connect to the PUMP/MV terminal on the Controller. The other Wire will connect to the COMMON or COM terminal. Wire size to connect the relay to the Controller will normally be 18 AWG. The relay can be located up to 800 feet (243 meters) away from the Controller using 18 AWG Wire.
The two red wires are labeled L1 OUT and L2 OUT. These wires will connect to the wires coming from the power source (120 or 240 VAC). Power wires from the power source and to the pump should be 12 AWG with a temperature rating of 55⁰.
The two black wires are labeled L1 OUT and L2 OUT. These wires will connect to the pump (120 or 240 VAC) wires.
The ground wires from the power source and the pump can be connected together in the Pump Start Relay box using a Wire nut.
Disclaimer: Hydro-Rain has made every effort to ensure that the information and recommendations contained within are correct. However, neither Hydro-Rain nor any of its employees warrants nor accepts any liability for the use of this information. National and local electrical codes should always be followed. Wiring, grounding, shielding, and bonding irrigation system components often require competent engineering judgment on a case-by-case basis. Competent engineering assistance should be sought from firms specializing in this field.