Installing a Dimmer Switch for a Light Fixture
I am replacing a dimmer switch that controls a light fixture and an outlet. In addition, there is one more black lead that goes somewhere
Dimmer Switch Wiring
Question: I am replacing a dimmer switch that controls a light fixture and an outlet. In addition, there is one more black lead that goes somewhere, not sure where. So while replacing the dimmer, I thought I would separate out the outlet from the light fixture. I have removed a pig tail to the switch and left with 4 black wires. I turned the breaker back on to figure out which black wire is the source back to the breaker. I can touch one wire to two others and get 120 volts on the MM. On the third wire, I get just under 40 volts. What causes only a 40 volt reading on the circuit?
This electrical question came from: Jason, a Homeowner from Whitefield, New Hampshire
See more about Home Wiring for New Hampshire
Additional Comments: Nice resource!
Thanks for your electrical question Jason
The Following links will assist you with your electrical question:
Wiring a Dimmer Switch
3 Way Dimmer Switch Wiring Diagram
Fully explained 3 way dimmer switch wiring diagram will take the mystery out of wiring a 3-way dimmer switch.
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Consult your Local Building Department about Permits and Inspections for all Electric Wiring Projects.
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The Safest Way to Test Electrical Devices and Identify Electric Wires!
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This is a testing tool that I have had in my personal electrical tool pouch for years, and is the first test tool I grab to help identify electrical wiring. It is a Non-contact tester that I use to easily Detect Voltage in Cables, Cords, Circuit Breakers, Lighting Fixtures, Switches, Outlets and Wires. Simply insert the end of the tester into an outlet, lamp socket, or hold the end of the tester against the wire you wish to test. Very handy and easy to use.
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Provides 6 probable wiring conditions that are quick and easy to read for ultimate efficiency
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The Wire Stripper and Wire Cutter
My absolute favorite wire stripping tool that I have had in my personal electrical tool pouch for years, and this is the tool I use to safely strip electrical wires.
This handy tool has multiple uses:
The wire gauges are shown on the side of the tool so you know which slot to use for stripping insulation.
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