Wiring a Switch Outlet Combination

By - Summary:

How to Wire a Combo Switch Outlet: These switch outlets are pretty handy and once the wiring designations are understood the wiring can be a snap.

Combination Switch and Outlet Combination

Electrical Question: I would like to replace a single light switch with a combination switch with pilot light and outlet.

  • The existing switch has two black screws and no ground screw.
  • The new device is a Cooper Wiring 274W-BOX Combination device with a switch, pilot light and an outlet.
  • It has a green screw (ground) and a silver screw on one side.
  • The other side has one brass screw and 2 black screws with the Break-off tab.
  • I want to wire so I can use the switch and the outlet independently (as it is show in the instruction sheet).
  • My old switch was wired with the HOT black wire connected to the first black screw, the other black wire (going to the light) connected to the second black screw.
  • The incoming and out coming white wires were connected together. I have also two grounded wire (incoming,out coming).
  • I connected the Cooper Wiring 274W-BOX device as follows:
    • Black HOT wire (incoming) connected to the upper black screw
    • Black wire (out coming) connected to the brass screw
    • Silver screw connected to the white wires
    • Green screw connected to the ground
      • NOTE : The Break-off tab is intact

The switch works well to put on/off the light. However, the outlet does not work if the switch is not at the ON position. The wiring instructions I used are identified with a star in the attached document (SINGLE POLE SWITCH AND GROUNDING RECEPTACLE – COMMON FEED (BRAKE-OFF TAB INTACT).

Please advise. Your help is greatly appreciated.


This electrical wiring question came from: Serge, a Homeowner from Montreal, Canada.

Dave’s Reply:
Thanks for your electrical wiring question Serge.

Wiring a Combo Switch Outlet

Application: Wiring a Combo Switch Outlet and Pilot Light.
Skill Level: Beginner to Intermediate – Best installed by a Licensed Electrician.
Tools Required: Basic Electricians Pouch Hand Tools and Voltage Tester.
Estimated Time: Depends on personal level experience and ability to work with tools.
Precaution: Identify the light circuit, turn it OFF and  Tag it with a Note before working with the wiring.
Notice: Installing additional fixture wiring should be done with a permit and be inspected.

How to Wire a Combo Switch Outlet

  • These switch outlets are pretty handy because they will allow you to have a switch and one outlet in the same single box location, however they can be a little tricky to understand, but once the switch outlet combo wiring designations are understood, the wiring can be a snap.
  • In this case, the locations of the two black wires will need to be swapped.
  • Here is an explanation of the screw terminals found on the combination switch outlet and what they are used for:
    • The Green Screw Terminal  is always the screw for the ground wire, which is commonly a bare copper wire or a green wire.
    • The Silver Screw Terminal is for the Neutral wire, or the white insulated wire.
    • The Single Black Screw Terminal is for the Black wire, or the black  insulated wire that leads to the light fixture.
    • The other Black Screw located at the Bridge or Brake-Off Tab is used as follows:
      • If the Tab is in place, then the same power used for the outlet will also be used for the light switch.
      • If the Tab is removed then this will allow a separate power source for the light, and a separate power source for the outlet.
        • Note: Typically, when one circuit or power source is shared for the light switch and the outlet, then the neutral wire is shared as well, so the neutral wire must be extended or pig-tailed out to the silver screw of the switch outlet combination device.

Electrical Tips for Wiring Switch Outlet Combination Devices

  • Always use a tester to positively identify the exact designations for the circuit wiring.In some wiring configurations, a white wire may be used to switch power.
  • In some cases a red wire may be used for power or switched power.
    If a switch outlet combination device is to be installed in a bathroom, kitchen, laundry room, or anywhere that is located near a sink or in a garage, then the switch outlet combination device must have a  GFCI outlet, or the circuit must be protected by another GFCI device or GFCI circuit breaker.
  • Check with the NEC code for the areas and locations required to protected by GFCI.

The Following will assist you with your Switch Outlet Combo:

Electrical Code

  • Home Electrical Codes

  • Electrical Code Directory covering afci-circuit, electrical-boxes, electrical-circuit, electrical-code-outlets, electrical-gfci, electrical-grounding, electrical-project, electrical-services, electrical-underground, electrical-wiring, electrical-wiring-code, lighting-codes and smoke-detectors.

Wiring Diagrams

Electrical outlet wiring

  • Wiring Electrical Outlet for the Home
  • Home electrical wiring includes 110 volt outlets and 220 volt outlets and receptacles which are common place in every home. See how wiring electrical outlets for the home are done.

Electrical wire

  • Electrical Wire for the Home
  • Complete listing of electrical wire types and parts used for home projects with electrical code information serves as selection guidelines.

junction boxes

  • Electrical Junction Boxes for Home Wiring
  • Understanding electrical junction boxes and what they are used for. Home electrical wiring is the process of installing electrical wire to a location that will serve electrical devices or an appliance. One very important component is the box where the wire will be installed. The type and size of the home wiring electrical boxes will depend upon the circuit size, application and its location.

For more information about Light Switch Wiring
Light Switch Wiring
Light Switch Wiring

  • Wiring a Light Switch – Diagram 1
  • Fully explained pictures and wiring diagrams about wiring light switches describing the most common switches starting with photo diagram 1.

Learn How to Wire it Right with my
Complete Guide to Home Electrical Wiring
Perfect for Homeowners, Students,
Handyman, Handywomen, and Electricians
Wiring GFCI Outlets
Wiring Home Electrical Circuits
120 Volt and 240 Volt Outlet Circuits
Wiring 3-Wire and 4-Wire Electric Range
Wiring 3-Wire and 4-Wire Dryer Cord and Dryer Outlet
How to Troubleshoot and Repair Electrical Wiring
Wiring Methods for Upgrading Electrical Wiring
Electrical Codes for Home Electrical Wiring
....and much more.

» Click here to learn more about Home Electrical Wiring «
  repair electrical wiring  

Be Careful and Be Safe - Never Work on Energized Circuits!
Consult your Local Building Department about Permits and Inspections for all projects.


Click the banner to Ask a Detailed Electrical Question and get an Instant Reply:
electrical question

FAQs Frequently Asked Questions and Comments

5 Responses to “Wiring a Switch Outlet Combination”
  1. Dave Rongey says:

    Hi Mark,
    Typically we use a voltage tester or a continuity tester to help identify the wiring for light fixtures and exhaust fans. In many instances when a cable has a white wire which has voltage and the black does not, then the white and black wire are being used for the switching process. For example: the light fixture would have a separate cable with the power source up at the light fixture, where the white wire is the power leading into the switch, and back wire is the switch controlled power that leads back up to the light fixture. The power originates at the light fixture from a separate cable.

    The power which was used for the combo outlet will need to be verified, as well as the wiring to the fan unit. The key will be to verify where the power source originates, then the wires that are used for the switching process.
    I hope this helps,

  2. Mark says:

    I am replacing a switch for a vanity light and a combination switch/outlet in the same box. The first switch controls the vanity light. The switch on the combo controls the exhaust fan and the outlet is not switched. The original switches were already removed so I don’t know how they were wired. There are two wires running into the box, the first one has the neutral wire hot and the black wire is not hot. The second wire has both wires hot. I believe that the first wire comes from the vanity light and the second comes from the fan. I am not 100% on which wire comes from which. This is the first floor of a two story house so there is no way to look at which wire comes from were. Can some one please tell me how to wire these so it will operate properly. I am usually decent at switch / outlet wiring but not this one. There are ground wires with each wire also.

  3. Dave Rongey says:

    Hi Joe,
    As you have described, the way the original 3 switches were wired within the frame was that the looped wire to all three switches was the Line of the power source. After that, each other wire connected to each light switch was the connected Load, such as a light fixture.
    Pilot light combo switches come in a few configurations and types, where the pilot light will be a neon light which is basically wired within the Load side of the switch, or an incandescent pilot light which requires a separate neutral wire.
    In any case, you will need to identify which pilot light you have in order to make the correct wire connections.
    The condition that you have described where one switch controls the other switches is because the load side of the first switch has been looped as the Line side of the other switches, therefore the wiring must be changed so that the Line side is configured properly for all of the other switches.
    To help you make the correct wiring connections, make sure to identify all of the wires properly, and then make the connections.
    I hope this helps you,

  4. Joe says:

    My question is similar to the one about wiring a Cooper 274W, but my switch does not have the outlet – only the pilot light. What is confusing me is that the old switch is part of a “gang” switch of 3 wall switches. The electrician who wired the house had the 2 black wires (Hot Line and Load) inserted into the back of the old switch and had “looped” a black wire (from one of the other switches) around one of the side screws (stripping off a portion of the insulation).
    I have wired the new switch as follows: hot to the top black screw, load to the top brass screw and the “loop” to the bottom brass screw.
    What I have is a pilot that is always on and the switch now controls everything in that gang switch assembly (the entire circuit) – when I switch it off, everything on the circuit goes off.
    What have I done wrong?

  5. robert ogrodny says:

    I need help installing this combination switch can someone please help me?


If you are asking a Quick Question please make sure it is about This TOPIC:
“Wiring a Switch Outlet Combination”

Comments Posted here are Open for Quality Discussion and Participation.