WHILE EXTREME CARE HAS BEEN IMPLEMENTED IN THE
PREPARATION OF THIS SELF-HELP DOCUMENT, THE AUTHOR AND/OR PROVIDERS
OF THIS DOCUMENT ASSUMES NO RESPONSIBILITY FOR ERRORS OR OMISSIONS,
NOR IS ANY LIABILITY ASSUMED FROM THE USE OF THE INFORMATION,
CONTAINED IN THIS DOCUMENT, BY THE AUTHOR and / OR PROVIDER.
Connections Instructions:
(as depicted in the diagrams above)
At the Fixture
box...
One cable entering this box coming from switch 2 .
* a) connect the white wire coming from switch 2 to
the grounded conductor (neutral) of the fixture.
* c) using an insulated wire nut connect black wire
from switch 2 + the switched ungrounded conductor
(hot) from light (shown as black in diagram) + the
switched ungrounded conductor (hot) from fan (shown
as red in diagram)
* d) please see under important notes in regards to
the equipment grounding conductor (bare wire).
At switch 1
box...
Two cables entering this box, one is the 'circuit
power supply' cable, and one cable coming from
switch 2.
* a) using an insulated wire nut connect / join the
white wire coming from the 'circuit power supply'
cable + the white wire coming from switch 2.
* b) connect the black wire coming from the 'circuit
power supply' cable to the common screw of switch 1.br />
* c) connect the red wire coming from switch 2 to
the one of the remaining main screws of switch 1.
* d) connect the black wire coming from switch 2 to
the last remaining main screw of switch 1.
**e) please see under important notes in regards to
the equipment grounding conductor (bare wire).
At switch 2
box...
Two cables entering this box, one cable coming from
switch 1 and one cable coming from the fixture.
* a) connect the black wire coming from fixture to
the common screw of switch 2.br />
* b) using an insulated wire nut connect / join the
white wire coming from switch 1 + the white wire
coming from fixture.
* c) connect the red wire coming from switch 1 to
one of the remaining main screws of switch 2.
* d) connect the black wire coming from switch 1 to
the last remaining main screw of switch 2
** e) please see under important notes in regards to
the equipment grounding conductor (bare wire).
Important Notes:
By electrical codes you MUST have at least 6 inches
of wire in the electrical box itself, and also the
wire must be able to reach at least 3 inches outside
the box, it can fail an electrical inspection if the
required min. wire length is not met. You may have
the wires a bit longer (within reason) but they
cannot be shorter. Also see the note on box fill
further down in this article.
Use wire nuts of the correct size to join wires
together. For fan / light combination fixtures, most
likely it will have wire connections, the white wire
will be the grounded conductor (neutral), any green
wires are equipment grounding conductors, then there
will be two other wires one will be the switched
ungrounded conductor (hot) for the light, and one
will be the switched ungrounded conductor (hot) for
the fan. If you are confused please post to our
forums for further clarification.
What is not shown in the drawings to avoid
confusion, is that each wire cable also has a bare
equipment grounding wire included. This wire is
connected to a grounding screw in each electrical
box (if the box is metal), joined either through the
grounding screws in the box itself or via a wire nut
to the bare wire of the next cable entering /
exiting the box, it is also connected to any
grounding screw (if there is one) on the switch
itself, as well as any grounding screw at the
fixture (green wires that attach to the fixture are
grounds). Now if using a plastic box, it is made of
a material that is non conductive, however some
plastic boxes have a metal strip inside that can
still be used to connect equipment grounding wires,
in the event that it does not use wire nuts to join
the bare grounding wires together. The equipment
grounding wire (bare in most cables) must be
electrical conductively joined throughout the
circuit. Green wires are also equipment grounding
conductors.
At the switch itself there are 3 main electrical
screws, one of these 3 screws is distinctly
different in color (perhaps darker) than the other
2. This screw connection is called the common screw.
It is very important that in order for the 2
switches to work as they are intended to that the
correct wire is attached to the common screw.
Basically as depicted in the drawings one switch has
the ungrounded conductor (hot) from the circuit
power supply cable attached to the common screw,
where the other switch had the ungrounded conductor
(hot) feed to the light fixture itself.
Please also note that there are a variety of
manufactures out there that make 3 way switches so
it is possible that the switch you buy may have the
common screw located in a different spot or side of
the switch then depicted in the drawings in this
article, just make sure that the wire depicted to go
to the common screw of each of the switches is
actually connected to the common screw of the 3 way
switch you bought. The other 2 wires going between
the remaining screws of one switch to the other
switch does not matter as long as one wire of the 2
remaining wires go on each of the remaining 2 screws
of the screw.
If there is an equipment grounding screw on the 3
way switch it may be green in color and be separated
away from the main connections of the switch and
likely part of the metal frame that is also part of
the mounting structure of the switch.
Extensions to
this Switch circuit...
Be Aware that there is a limit by code on how many
wires can be in a given size electrical box, when
adding more wires to the same box you may have to
install a larger and / or deeper box to allow space
for more wires coming and out of the box.
Here is an article / explanation in regards to box
fill calculations '
Box
Fill Calculation'
The instructions here are based on the fact that the
circuit has already been wired to the configuration
shown in this article and we are now making the
wiring changes for onward power.
From the switch
locations....
Only always on power is available from the switch 1
location. Switch 2 only has onward switched power
available.
Switch 1
options...
Onward Always On Circuit Power...
(showing bellow the switch portion of the circuit)
Not shown in the diagram
but the onward cable also has a bare wire
(equipment grounding conductor) that also must
be connected to all the other bare wires at the
switch electrical box.
Connection
Instructions for onward cable (always on)
* a) Using an insulated wire nut, attach / join
- the white wire of onward cable + the white
wire from 'circuit power supply' cable + the
white wire coming from switch 2.
* b) Using an insulated wire nut, attach / join
- the black wire of onward cable + the black
wire connected to common screw of switch 1 + the
black wire coming from 'circuit power supply'
cable.
Identification of wires in onward cable....
Black - Ungrounded conductor (hot - always on)
White - Grounded conductor (neutral)
*************
Switch 2
options...
Onward switched power...
(showing bellow the switch portion of the
circuit)
Not shown in the
diagram but the onward cable also has a
bare wire (equipment grounding
conductor) that also must be connected
to all the other bare wires at the
switch electrical box.
Connection Instructions for onward cable
(switched)
* a) Using an insulated wire nut, attach
/ join - the white wire of onward cable
+ the white wire coming from fixture +
the white wire coming from switch 1.
* b) Using an insulated wire nut, attach
/ join - the black wire of onward cable
+ the black wire connected to common
screw of switch 2 + the black wire
coming from fixture.
Identification of wires in onward
cable....
Black - Switched Ungrounded conductor
(hot - switched)
White - Grounded conductor (neutral)
************
From
the fixture location...
At the fixture location only switched
onward power is available.
(showing bellow the fixture portion of
the circuit)
Not shown in the diagram but the onward
cable also has a bare wire (equipment grounding conductor) that
also must be connected to all the other bare wires at the
fixture electrical box.
Connection Instructions for
onward cable (switched)
* a) Using an insulated wire nut, attach / join - the white wire
of onward cable + the white wire connected to the grounded
conductor (neutral) of fixture + the white wire coming from
switch 2.
* b) Using an insulated wire nut, attach / join - the black wire
of onward cable + the black wire coming from switch 2 + the
switched ungrounded conductor (hot) from light (shown as black
in diagram) + the switched ungrounded conductor (hot) from fan
(shown as red in diagram)
Identification of wires in
onward cable....
Black - Switched Ungrounded conductor (hot - switched)
White - Grounded conductor (neutral)
Foreign Users:
The colors of the wires depicted
are based on the standards and code requirements / configuration
in the United States and Canada. If you are viewing this site
from a foreign country, your wiring standards and color of wires
may be different but the principal and sequence of wiring will
still remain the same. Therefore the information in this article
may still be of use to you regardless of what country you may be
in. Just translate the colors used here to the color of wires
used in your country in regards to ungrounded (hot) conductors /
grounded conductors (neutral) and equipment grounding con
