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.
You will need...
1. A 4 wire cable that is routed between switch box 1 and switch box
2 - these wire cables comes with a black / red / blue (or white
striped) / white wire plus the bare equipment grounding wire.
2. A 3 wire cable that is routed between switch box 2 and switch box
3 - these wire cables comes with a black / red / white wire plus the
bare equipment grounding wire.
3. A 2 wire cable that is routed between switch box 3 and the
fixture box - this wire cable comes with a black / white wire plus
the bare equipment grounding wire.
4. A circuit power supply source wire cable that is routed to switch
2.
5. Insulated wire nuts to connect / join wire together, variety of
sizes out there so make sure you obtain the correct size.
6. Wire staples, to affix the wire cables to wall studs as needed.
Wire cable must be secured within 6 inches of entering the
electrical box.
7. Wire cable / wire strippers.
8. Screwdrivers as required.
Holes drilled to feed wires through studs must be 1 1/4" from edge
of stud, in instances where the wire cable is closer then the edge
of stud must have a 1/16-in. thick protective metal plate over the
area where the cable is being feed through (may want to notch the
stud so that that the protective plate does not create a bump on the
drywall). Also read the article called
'Wire Routing Basics'
Wire cables entering the electrical box - secure the cable clamp at
the box snug enough that the cable cannot come out but not too tight
as to pinch the cable and break through the insulated cover of the
cable.
You must have at least 6 inch length of wire inside the electrical
box, it can be a bit more
but not
less, it can fail an inspection if the length of each wire is less
than 6 inches. Also read the article called '
Box
Fill Calculations' as there is a limit on how many
wires are allowed for a certain size electrical box.
STEP 1 - Make
certain that the power supply cable is dead - turn off the
electrical breaker at the service panel. Make certain that everyone
in the house is aware of what you are doing so that they do not get
the notion to reset the breaker when another light in the home is
not working.
STEP 2 - Make the
box openings (if a existing home)
STEP 3 - Feed /
Route the wire cables.
STEP 4 - Mount /
Install the Electrical Boxes (make sure the electrical boxes are
secured as some fixtures are heavy and may require additional
support) [The electrical box should not extend beyond the edge of
the finished wall or ceiling so that the fixture can mount flush to
the ceiling and the wall switch cover will mount flush - but it also
should not be recessed too far into the wall or ceiling]; then feed
the wire cables into the electrical boxes. Sometimes because of
tight openings in existing homes, the wire cable may to be feed into
the electrical box then the box put in position and secured.
STEP 5 - Connect
the wires...
Connections Instructions:
(as depicted in the diagrams above)
At the Fixture box...
One cable entering this box, coming from switch 3.
* a) connect the black wire coming from switch 3 to the switched
ungrounded conductor (hot) of fixture (shown as black in
picture) - if the fixture has screw type connections then
connect to brass color screw.
* b) connect the white wire coming from switch 3 to the grounded
conductor (neutral) of fixture (shown as white in picture) - if
the fixture has screw type connections then connect to the
silver color screw.
* c) please see under important notes in regards to the
equipment grounding conductor (bare wire).
At switch 1 box...
One cables entering this box, coming from switch 2.
* a) connect the black wire coming from switch 2 to common screw
of switch 1.
* b) connect the red wire coming from switch 2 to the one of the
remaining main screws of switch 1.
* c) connect the blue wire coming from switch 2 to the last
remaining main screw of switch 1.
* d) using and insulated wire nut cap off the white wire.
* e) please see under important notes in regards to the
equipment grounding conductor (bare wire).
At switch 2 box...
Three cables entering this box, one cable coming from switch 1,
one cable coming from switch 3, and one cable being the 'circuit
power supply cable'
* a) using an insulated wire nut connect / join the white wire
coming from switch 3 + the white wire coming from the 'circuit
power supply cable' + the white wire coming from switch 1.
* b) using an insulated wire nut connect / join the black wire
from switch 1 + the black wire coming from the 'circuit power
supply cable'
* c) connect the red wire coming from switch 1 to the one screw
that is a matching pair of screws on switch 2 (both the red and
blue wires coming from switch 1 must go to a matching pair of
screws at switch 2)
* d) connect the blue wire coming from switch 1 to the 2nd screw
that is a matching pair of screws on switch 2 (both the red
and blue wires coming from switch 1 must go to a matching pair
of screws at switch 2)
* e) connect the red wire coming from switch 3 to one screw from
a different matching pair of screws. (both the red and black
wires coming from switch 3 must go to a matching pair of screws
at switch 2)
* f) connect the black wire coming from switch 3 to the 2nd
screw that is a matching pair. (both the red and black wires
coming from switch 3 must go to a matching pair of screws at
switch 2)
***Just to clarify further - The
red and blue wires coming from switch 1 go to one set of
matching screws at switch 2 -- The red and black wires coming
from switch 3 go to a different set of matching screws at switch
2 - A matching set is 2 screws of the same color.***
* g) please see under important notes in regards to the
equipment grounding conductor (bare wire).
At switch 3 box...
Two cable entering this box coming from switch 2, and one coming
from fixture.
* a) connect the black wire coming from fixture to the common
screw of switch 3.
* b) connect the red wire coming from switch 2 to one of the
remaining main screws of switch 3.
* c) connect the black wire coming from switch 2 to the last
remaining main screw of switch 3.
* d) using an insulated wire nut connect / join the white wire
coming from switch 2 + the white wire coming from fixture.
* e) please see under important notes in regards to the
equipment grounding conductor (bare wire).
I
mportant 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.
If the fixture has screw type connectors, the ungrounded
conductor (hot) is connected to the brass color screw, and the
grounded conductor (neutral) is connected to the silver color
screw. If it has black and white wires coming from fixture, then
just connect black to black and white to white. Use wire nuts of
the correct size to join wires together.
The wire cable running between switch 1 & switch 2 has 4 wires
in it - black / red / blue / white (plus the bare equipment
grounding wire). The wire cable running between switch 2 &
switch 3 has 3 wires in it - black / red / white (plus the bare
equipment grounding wire).
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 3 way switches (switch 1 & 3) 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
all the 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
switch.
At the 4 way switch (switch # 2) there are 2 sets of matching
screws, one set will match in color and the other set will be
distinctly different perhaps darker in color, it is important
that the traveler wires from the previous switch are connected
to one matching set, and the traveler wires going to the next
switch are connected to a different matching set.
If there is an equipment grounding screw on the 3 way or 4 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.
F
rom the fixture location...
Only switched onward power is available from the fixture
location.
Onward switched power...
(example more than one light fixture controlled by the same
switches)
(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, connect / join - the black
wire from switch 3 + the black wire connected to the switched
ungrounded conductor (hot) of fixture + the black wire of onward
cable.
* b) Using an insulated wire nut, connect / join - the white
wire from switch 3 + the white wire connected to the grounded
conductor (neutral) of fixture + the white wire of onward cable.
Identification of wires in
onward cable....
Black - Switched ungrounded conductor (hot - switched)
White - Grounded conductor (neutral)
**************
From the switch locations....
Switch 1 options...
Only onward 'always on' power is available at the switch 1
location.
Onward 'Always On' Power
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, connect / join - the black
wire coming from switch 2 + the black wire connected to the
common screw of switch 1 + the black wire of onward cable.
* b) Using an insulated wire nut, connect / join - the white
wire from switch 2 + the white wire of onward cable.
Identification of
wires in onward cable....
Black - Ungrounded conductor (hot)
White - Grounded conductor (neutral)
*************
Switch 2 options...
(only onward always on power available)
Because of the number of wires depicted at switch 2 in this
design I have decided to not create a drawing but just to make
connection instructions for switch 2 onward options...
Onward always on power...
Connection Instructions for onward cable (always on state)
* a) Using an insulated wire nut, connect / join - the black
wire from the 'circuit power supply cable' + the black wire
coming from switch 1 + the black wire of onward cable.
* b) Using an insulated wire nut, connect / join - the white
wire from switch 3 + the white wire coming from the 'circuit
power supply cable' + the white wire from switch 1 + the white
wire of onward cable.
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 2 electrical box.
Identification of wires in
onward cable....
Black - Ungrounded conductor (hot)
White - Grounded conductor (neutral)
***************
Switch 3 options...
Only onward switched power is available at the switch 3
location.
Onward switched power...
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, connect / join - the black
wire coming from fixture + the black wire connected to the
common screw of switch 3 + the black wire of onward cable.
* b) Using an insulated wire nut, connect / join - the white
wire from fixture + the white wire coming from switch 2 + the
white wire of onward cable.
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 conductors
as well know applicable code requirements in your country.
