How To Wire a Sprinkler Irrigation Valve

How To Wire a Sprinkler Irrigation Valve

This tutorial demonstrates techniques for wiring Irrigation Valves for DIY and professional sprinkler system installations. We have provide example illustrations for both wiring single valves in a succession of valves and wiring valves located together in a manifold.

Type of Wire Used for Sprinkler Irrigation Systems: Direct Burial Wire should always be used to wire underground Sprinkler Systems. Direct Burial Wire is specially designed to be trenched underground without the use of conduit around it.  This make it possible to lay your irrigation wire at the same time as your main tubing lines and eliminated the need for further protection of the wire cables. 18 Gauge wire is most commonly used for Sprinkler Irirgation Installation and is commonly available with 2 to 12 conductors on a single cable. 

Connectors Used For Sprinkler Irrigation Wire: Use Silicone filled weatherproof connectors for all Sprinkler Irrigatoin and Landscape Lighting wiring installations.

Steps to Wiring Irrigation Valves

1. Design Your Valve Layout

Prior to determining your wiring approach you must first plan the layout for your valves.  As illustrated in our Irrigation Design tutorials many Sprinkler Irrigation systems are designed with a slightly larger header tube to which zones branch off from at various locations throughout the property.  In this case you would determine the number of valves in the system and install the wire with the header tubing and the length of wire needed would be approximately equal to the length of your main header line.  In other cases, a manifold may be used where several header lines branch off from a central location.  In these cases you simply need enough wire to go from your Irrigation Controller to the Valve Manifold. 

2. Determine Number of Conductors for Wiring.

Once you have determined the layout of your Valves for you Sprinkler System you can determine the number of conductors needed for your Direct Burial Irrigation Wire.  You will need one conductor for each solenoid valve and another conductor as a common wire. For example if you have 5 solenoid valves in your Sprinkler System you would need to purchase 6 conductor (18/6) direct burial cable.  You always need 1 more conductor than the number of valves in the system. 

Alternatively if your valves are grouped in different areas you can consider using two different cables for different areas.  For example if you have the same 5 valves but 2 are located in the front yard and 3 are located in the back yard you could use a 3 conductor cable (18/3) for the front yard and 4 conductor (18/4) for the back yard.  You can then splice together the two common conductors from each cable at the controller for the same effect as havig one cable. 

3. How To Connecting The Solenoid Valves.

Single Solenoid Valve Wiring

This photograph illustrates wiring of a single valve with the Direct Burial cable continuing to another valve location.  The following steps are involved in this wiring method.

1. Carefully remove 3-4 inches of outer covering for all conductors in the cable.  This can be done with a standard wire stripper or carefully with a sharp utility knife.  Care must be taken not to damage the outer cover of indiivual conductors.

2. Cut the common wire (white is most often used) in the middle of the area that has been stripped.

3. Cut the chosen conductor (black in this illustration) at the end of stripped area that leads to the next valve.  This conductor will no longer be used for future valves.

4. Create a loop with the stripped area.  This will have the impact of giviing more slack for connecting your common white wire to the solenoid.

5. Connect one lead wire from the Irrigation Valve to the chosen conductor (black in this case) using a silicone filled weatherproof connector nut.  Connect the other lead together with both sides of the common white wire.  For this illustration we have used a Schotchlok connector for the single connection and a regular weatherproof nut for the common wires (recommended for multiple condutor connections).


Wiring Irrigation Valves in a Manifold Configuration.

This photograph illustrates wiring of a manifold of Irrigation Valves.  We have assumed for the purposes of this illustration that the valves are at the end of a cable run and therefore no mid-cable splicing (as above) is needed..

1. Carefully strip the last 3-4 inches of outer covering for all conductors in the cable.  Once again care must be taken not to damage the outer cover of indiivual conductors.

2. Connect one lead wire from each solenoid valve to one of the conductor wire.  The colour of wire chosen should be noted for each valves to allow for easy isolation of problems that may arise.

4. Connect all alternate leads from the solenoids to the common white wire. 

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