The most common smart device in use is the ubiquitous light switch. A smart light switch can improve the comfort and safety of a home in numerous ways. Lights can automatically spring to life just before you wake up in the morning and turn themselves off when you go to bed.
They can light your path when you arrive home in the evening or turn night into day when they detect suspicious activity around your home. And none of these actions require any effort on your part.
But before you invest in smart lighting, you must ensure that they're compatible with the wiring in your home. Most smart lights require a neutral switch wire to work properly.
Exactly, what is a neutral wire on a light switch? Before discussing the purpose of a neutral wire, it's helpful to understand how wall switch wiring works. There are three types of wires in almost all light switches: 1) hot wires, 2) a neutral wire, and 3) a ground wire.
- What are Hot Wires?
- What is a Neutral Wire?
- What is a Ground Wire?
- Smart Switches are Never Off
- What if You Don't Have a Neutral Wire?
Hot wires are how electricity moves from the power source, like a battery, or in the case of residential homes, from a transformer to the “load,” or device requiring power, like a light bulb or other appliance.
The term “hot” wire means that it's always carrying electricity. Touching a hot wire will result in an electrical shock that can cause severe injury or death because a power source always supplies it with energy.
North American building codes require two “split phase 240 volt current” wires in homes built since the 1980s. Split phase means each wire carries 120 volts of electricity, totaling 240 volts.
Each light switch with neutral wire in your home will have two hot wires, identified by their black casings. However, not every hot wire will be black. Some will be red, blue, or yellow, but those colors usually signify that the wires are being used for additional functions and not just powering a device.
Exactly, what is the neutral wire in a light switch used for? Essentially, electricity requires a closed loop for it to flow. That means electricity from the source (i.e., battery or transformer) flows through the switch and into the powered device, passes through, and then flows back to the source. If the loop is broken, the current stops or finds another path and will electrify some unintentional object, which can be extremely dangerous if you touch it. How to Wire a Neutral Safety Switch
Since hot wires carry current to a device, that current needs a way to get back to the source. And that's the function of a smart switch neutral wire, to take current from the powered device back to a busbar connected to the electrical panel, thus completing the circuit. But what is no neutral wire smart switch ?
You can identify neutral wires by looking for a white or gray casing. Typically, neutral wires aren't carrying a current when a device is off. Nevertheless, they should always be handled with extreme caution, just like hot wires. A single mistake can be catastrophic and cause severe injury or death.
The ground wire plays a vital safety role in the electrical wiring in your home. It acts as a safety valve in the unlikely event that the power distribution in your wiring becomes “unbalanced.”
Usually, the ground wire doesn't carry an electrical current. But when the occasional accident occurs, like a short circuit, it diverts rogue electricity out of the electrical wiring in your home and into the earth outside.
For example, if your home receives a power surge from your electric utility, the ground wire will divert the excess electrical power into the ground. It'll also trip the circuit breaker in your electrical panel to shut off the electricity for added safety.
Without a ground wire, power surges from your utility company, or a lightning strike will cause appliances plugged into electrical outlets to explode, which would certainly ruin your day!
Ground wires usually have a green casing; however, not all homes are grounded. Homes built since the 1980s will have three-prong electrical outlets, signifying that grounding is present. If your outlets only have two prongs, then most smart lights won't work correctly in your home.
One last point, never alter the ground prongs on your device plugs or tamper with the ground wiring in your home, or you face a serious risk of electrocuting yourself.
Now that you understand how electricity flows to smart lights, it'll be easy to understand the importance of a neutral wire for light switch capability.
Smart switches must have current flowing through them at all times to work their magic, which means the neutral wire in light switch boxes is always “hot.” Without a neutral wire, your smart light can't receive signals when the switch is off because the circuit is broken, stopping the power from flowing through the bulb. However, with a neutral wire, power continues to flow even with the light switch turned off.
How do you know if your home has neutral wiring? The best way is to look for one or more of the following clues to determine if your house can properly use smart lighting devices:
- Homes constructed in the mid-80s or later, probably have neutral wiring throughout the house.
- You probably have neutral wiring if there's an electrical outlet near your light switch.
- Light switches that are grouped together will almost always have a neutral wire.
Finally, if you're still in doubt about the wiring in your home, you can always take off the switch plate and look. But never do that without turning off the power to the switch or to your entire home. If it's there, you'll know what to do with the neutral wire in the light switch boxes in your home.
Should you discover that you don't have neutral wiring in your home, does that mean you can't take advantage of smart home technology to make your life safer and more comfortable? Absolutely not! You have several options available to you to overcome this dilemma.
- Rewire Your Home — Since most smart light switches require a neutral wire, you might consider rewiring your entire home, if possible, to make it capable of supporting smart devices. This option, however, has the distinction of being the most expensive, hence, least desirable.
- Use Smart Bulbs — A far less expensive and simpler solution is to purchase smart bulbs that don't require a neutral wire switch. This approach has the advantage of being highly cost-effective, but it also has the drawback back of limiting your lighting capabilities. Primarily, if the light switch is off, your smart bulb is no better than a dumb light. Do you really want to hassle your entire family to remember to leave every light switch in the house in the “on” position so your bulb can communicate with your lighting schema?
- Choose No-neutral Smart Lighting — The best option may be to purchase smart lighting devices that don't require a neutral wire on light switch wiring but can still function at all times, like the Evvr In-Wall Relay Switch. This option is slightly more expensive than buying a bunch of bulbs but far less than rewiring your home, yet you get the full capabilities of living in a smart home with intelligent lighting.
Evvr In-Wall Relay Switch — the Ideal Solution
Avoid ripping apart your walls trying to rewire the electrical system in your home when the Evvr In-Wall Relay Switch can do the job at a fraction of the cost. This smart light switch features a split single live wire in-wall switch, which is divided into two modules, a Smart Relay and a Smart Switch Sub-Assembly.
Smart Relay uses standard Zigbee 3.0 wireless technology and is effective with different loads, including incandescent lamps, halogen lamps, LED lamps, and fluorescent lamps. Its compact size can be installed in any light fixture box. This device is compatible with devices for remote control and inter-operation.
Smart Switch Sub-Assembly is an optional component of the In-Wall Relay Switch when they are used together. The Smart Switch Sub-Assembly is designed to allow mechanical switch panels to work with switch commands from the Zigbee network.
There's no shortage of capable smart lighting systems you can buy locally or online. When shopping, make sure you choose one that works with the wiring in your home to avoid any serious financial mistakes.
The Evvr In-Wall Relay Switch can save you significant time and money whether you have neutral wiring in your home or not, but you'll save a bundle if you don't.
Once you find the right system, you'll marvel at how you ever got along without the comfort, convenience, and safety of smart lighting in your life. Evvr can offer you a comprehensive smart home solution whether you are an integrator, professional installer, distributor, or DIYer. Get in touch with us and become our partner today!