Pump Start Relay Wiring Diagram: All You Need to Know

If you are in the process of installing a new irrigation system or upgrading your existing system, you may have heard about the pump start relay. This device is used to automatically turn on and off the pump when the irrigation system is activated or deactivated. It is a crucial component of any irrigation system, and the wiring diagram is an essential piece of information that you need to understand to install it correctly.

What is a Pump Start Relay?

A pump start relay is an electromechanical device that automatically controls the operation of the irrigation system’s pump. It receives signals from the irrigation controller and turns the pump on or off based on those signals. The relay is usually installed near the pump, and the wires from the irrigation controller and pump are connected to it.

The pump start relay has two main components: the coil and the contacts. The coil is an electromagnet that generates a magnetic field when it is energized. The contacts are switch-like devices that open and close when the coil is energized or de-energized, respectively. The contacts are used to control the pump’s power supply, and when they are closed, the pump is turned on, and when they are open, the pump is turned off.

How Does a Pump Start Relay Work?

When the irrigation controller sends a signal to start the irrigation cycle, it also sends a signal to the pump start relay. The signal energizes the coil of the relay, generating a magnetic field. The magnetic field attracts the contacts, closing them and completing the circuit that supplies power to the pump. The pump starts running, and water is pumped to the irrigation system’s pipes.

When the irrigation cycle ends, the controller sends a signal to stop the pump. The signal de-energizes the coil of the relay, and the magnetic field disappears. This causes the contacts to open, interrupting the power supply to the pump. The pump stops running, and the water flow to the irrigation system stops.

Why Do You Need a Pump Start Relay?

There are several reasons why you need a pump start relay in your irrigation system. Firstly, it eliminates the need to manually turn the pump on and off every time you want to irrigate your lawn or garden. This saves time and effort and ensures that your irrigation system runs smoothly and efficiently.

Secondly, a pump start relay prevents damage to your irrigation system. If the pump runs dry, it can cause damage to the pump and the irrigation system’s pipes. With a pump start relay, the pump only runs when water is available, reducing the risk of damage.

How to Wire a Pump Start Relay?

Wiring a pump start relay is a straightforward process that involves connecting the wires from the irrigation controller and the pump to the relay’s terminals. The wiring diagram for the pump start relay is as follows:

Terminal Wire Color Description
1 Black Power supply from the controller
2 Red Power supply to the pump
3 Green Ground

Once you have the wiring diagram, follow these steps:

Step 1: Turn off the Power Supply

Before starting the installation process, turn off the power supply to the pump and the irrigation controller. This will prevent electrical shock and damage to the devices.

Step 2: Mount the Pump Start Relay

Mount the pump start relay near the pump, using screws or a mounting bracket. Make sure that the relay is securely mounted and will not move or vibrate during operation.

Step 3: Connect the Wires

Use wire strippers to strip the ends of the wires that will be connected to the relay’s terminals. Connect the black wire from the controller to terminal 1, the red wire from the pump to terminal 2, and the green wire to terminal 3. Tighten the terminals using a screwdriver.

Step 4: Test the System

After connecting the wires, turn on the power supply to the pump and the irrigation controller. Test the system by activating the irrigation cycle from the controller. The pump should start running, and water should flow through the irrigation system. If everything works correctly, you have successfully wired the pump start relay.

FAQ

Q: What is a pump start relay, and how does it work?

A: A pump start relay is an electromechanical device that automatically controls the operation of the irrigation system’s pump. It receives signals from the irrigation controller and turns the pump on or off based on those signals. It has a coil and contacts that open and close to control the pump’s power supply.

Q: Why do I need a pump start relay in my irrigation system?

A: A pump start relay eliminates the need to manually turn the pump on and off every time you want to irrigate your lawn or garden. It also prevents damage to your irrigation system by ensuring that the pump only runs when water is available.

Q: How do I wire a pump start relay?

A: Wiring a pump start relay involves connecting the wires from the irrigation controller and the pump to the relay’s terminals. The wiring diagram is simple and easy to follow, and the process involves turning off the power supply, mounting the relay, connecting the wires, and testing the system.

Q: Where should I mount the pump start relay?

A: The pump start relay should be mounted near the pump, using screws or a mounting bracket. It should be securely mounted and should not move or vibrate during operation.

Q: How do I test the pump start relay?

A: To test the pump start relay, turn on the power supply to the pump and the irrigation controller, activate the irrigation cycle from the controller, and check whether the pump starts running and water flows through the irrigation system.

By following the guidelines above, you can wire a pump start relay correctly and ensure that your irrigation system runs smoothly and efficiently. The pump start relay is a simple yet essential component of any irrigation system, and understanding its wiring diagram is crucial for its proper installation and operation.