How to Wire a 2 Wire Solenoid Valve (Expert Steps)

At the end of this guide, you should be able to wire and operate your 2-wire solenoid valve with ease.

One of the most common issues after purchase is wiring the 2-wire solenoid, which I am going to address in this guide. I will also tackle some FAQs and provide viable solutions. I have over a decade of experience dealing with solenoids and have done a ton of repairs and I want to teach you how to do this so you can save some money on costly repairs. 

Let’s get started.

In General, to wire your 2-wire solenoid valve, identify the two terminals on the solenoid – the Start and Battery terminals. Then start connecting the solenoid. Attach the white wire of the multi-conductor irrigation cable to one wire from each of the solenoids. Next, link the other wires to a separate-colored wire. You may record the color for all the zones for future reference. Finally, ground the pull in and hold windings appropriately.

I’ll go into more detail below.

Getting Started: What the Two Wires on a Solenoid Represent

There are two terminals on a solenoid valve; the battery or B terminal and the start or S terminal.

Terminal B/battery Terminal

This terminal represents the direct connection to the live cable of the solenoid.

Terminal S/start Terminal

This is where power flows from the ignition system/switch.

What is the Best Method to Connect the Solenoid Valve?

Follow the procedure below to wire your solenoid valve accurately:

Step 1

Identify the common wire of the multi-conductor irrigation cable – it is usually colored white.

Step 2

Use a wire stripper to remove the insulation coating to about 0.5 inches from the wires.

Step 3

Connect it (common cable) to one wire from each solenoid by twisting them.

Step 4

Nest the twisted end in a wire cap and reinforce the connection with duct tape.

Step 5

Connect the other wires to a separate-colored cable.

Step 6

Then, record the colors for each zone in a book or phone for future reference. (1)

Do the Sides of Solenoid Valves Have Positive and Negative Terminals?

The presence of positive and negative connections or surfaces in the circuit indicates electrical polarity.

One common solenoid FAQ is about the solenoid valve sides having electrical polarity. No, electrical polarity does not matter in solenoid valves. So, you can connect the hot and ground cables on either side of the valve interchangeably. (2)

Why Should you Ground your Solenoid?

The hold and pull-in wire turns on the solenoid and requires grounding. There are two circuits in the solenoid; one is a heavy pull in the winding, and the other is a lighter hold winding.

If the heavy pull-in winding has an open circuit, the starter cannot engage.

Wires on The Starter Solenoid

This is another FAQ; most people cannot trace the wires connecting to the solenoid’s starter. Here is the solution:

A typical starter has one small white connector for the starter control cable, and two large terminals: one for the thick wire that powers the starter motor, and the other for the hot cable of the battery.

Why Do Solenoid Valves Have Three Cables Connected to Them?

WALCHEM valve
Video | Walchem

The XR33 actuator controls the position of the valve, and it connects to three cables. The ground is attached to the neutral cable – black wire. The power flows to the positive wire – the red wire. And finally, the green wire is the control wire, changing the position.

Take a look at some of our related articles below.




References
(1) phone – https://www.pcmag.com/picks/the-best-phones
(2) electrical polarity – https://www.techtarget.com/whatis/definition/polarity

Video References

Access Irrigation Ltd

Walchem

About Sam Orlovsky

b1d87d2ee85af3e51479df87928bdc88?s=90&d=mm&r=gI realized early on carpentry was a huge passion for me and I’ve stayed in the industry for over 20 years now. This gives me a unique ability to really be able to tell you what the best tools and recommendations are. I’m not only a carpenter but I also like machinery and anything to do with electrics. One of my career paths starting off was as an apprentice electrician so I also have a lot of experience with electrical products and anything related.