However, we are getting some of repeat questions when it comes to 3-Way switches.
We have added kits that help simplify your 3-Way WA-100 switch purchase. Below is some information that should help.
Definitions
Single pole: Your ‘average’ switch- the light is controlled from one location.
3-way: When the light is controlled from two locations. Also called upstairs/downstairs switches in some regions.
Primary switch: In a 3-way installation, the Primary switch contains the Z-Wave chip. The device used in Single pole applications is the Primary - same device.
Auxiliary switch: In a 3-way installation, the Auxiliary switch gives an alternate switch location. An Auxiliary switch CANNOT be used by itself as a Primary switch and is only used with a Primary.
Load: The light, fixture, or other item you want to turn on/off/dim.
Line: The source of the electricity from the electric box/fuse box.
Neutral: The return route of electricity. When installing a Smart Switch, a neutral is required. See What to Know Before Changing Your Wall Switch for more on Neutrals.
Traveler Wire: Also called the "common" wire, this power line is fed into the common terminal of one of the switches.
Toggle: Type of switch that sort-of looks like an older ‘standard’ switch, and will fit toggle face plates. We do not have any ZWP toggle dimmers or toggle switches, but they are available from GE/JASCO
Rocker: (also called a paddle switch or known by a brand name "Decora") Type of switch with a wider surface than the toggle. Most modern homes have rocker switches, and this is among the first upgrades done by DIYer’s.
Understanding 3-way Circuits
A 3-way switch is a setup where a load is controlled from 2 locations. There are also 4-way (3 locations), 5-way (4 locations) and even 6-way (5 locations) or more. For Z-Wave purposes (and this blog entry) we are writing about how to install ZWP 3-Way Smart Switches. NOTE: most Z-Wave devices will support up to a 5-way switch.
Why is it called a 3-way? I’ve been told that it’s because there are 3 ways for the electricity to flow, or that originally there were 3 points of contact. Nothing seems to make sense to me, and I will leave the nomenclature for electricians and scholars. The average DIY handyman/woman will need to know a single pole switch and a 3-way.
You’ve got a 3-way that you want to add to your Z-Wave network. Now what? The first step in automating your basic 3-way setup is identifying the wiring. There are at least 5 ways of wiring a 3-way switch, and each of those will require a slightly different setup. As we do not give electrical advice on this blog, we will assume you have the “standard” way that professionals will wire a 3-way circuit and refer to the wiring diagram below (full instructions available here). Know that there may be other ways before you play “Eeny, meeny, miny, mo” (yes, it happens) with the ‘extra’ wires. When in doubt, please call an electrician.
What is an Auxiliary Switch?
Smart switches can be broken up into 2 main categories: Primary Switches and Auxiliary Switches. A Primary (also known as a Master) switch contains the Z-Wave chip. It’s the more expensive of the pair. If you are only replacing one switch (non 3-way) then you would choose a Primary switch and be done.
An Auxiliary (also known as a slave or add-on) switch gives an alternate location to control the Primary switch. An Auxiliary switch will not control a load, or even work with a Z-Wave network since it does not have a Z-Wave chip. An Auxiliary is required when you want to automate a 3-way circuit. The old, existing dumb switch will NOT serve as an Auxiliary switch. A Primary Switch and Auxiliary Switch will NOT communicate wirelessly; you need the existing wiring that supported the dumb 3-Way switches.
What is the difference in Model Numbers?
(Click on the model number to open the product page in a new tab).
The WD-100 is an in-wall Z-Wave Plus Multi-level Light Dimmer
The WS-100 is an in-wall Z-Wave Plus ON/OFF Light Switch
The WA-100 is an in-wall Auxiliary Switch for both of the above
NOTE: Auxiliary switches will ‘become’ the type of device it supports; a dimmer becomes a dimmer; a switch becomes a switch.
The KITZWP-WD-WA-100 is a Dimmer/Auxiliary Switch set for 3-Way applications
The KITZWP-WS-WA-100 is an ON/OFF Switch/Auxiliary Switch set for 3-Way applications
Multi-gang Switch Boxes
When you have multiple switches in the same box, this is called a multi-gang switch installation. Although you MAY have one or more 3-way circuits in a multi-gang box, each of the switches in that box will be it's own circuit. Handle these like any other single gang installation with one caveat: You may not be able to fit multiple Smart Switches next to one another. In this case follow the manufacturer's instructions on how to clip/break off the heat sink tabs on the sides of the switch. This will allow you to fit more switches side-by-side, but removing tabs will decrease the load rating of the switch. Read the instructions that come with the switch for more information.
NOTE: This is an updated version of a previous blog that specified GE/JASCO devices instead of ZWP devices.
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