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Electrician HELP..

Willie B

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Jan 2, 2016
Messages
4,079
Location
Mount Tabor VT
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Electrician
Not so complicated. It's a round trip. Usually done with both two conductor cable & 3. Use wire nuts to provide the grounded conductor to the "bulb".
Supply hot power to the pivot of one switch.
Connect the other terminal of the bulb to the pivot of the other three way switch."Travellers" between the switches.

Another switch is an X or pass through. Flipping any switch makes the light change.

There are about 100 rules to do it safely, but that is the basic stuff.

3 way.jpg
 

Nige

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Joined
Jun 22, 2011
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29,855
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G..G..G..Granville.........!! Fetch your cloth.
Not so complicated. It's a round trip. Usually done with both two conductor cable & 3. Use wire nuts to provide the grounded conductor to the "bulb".
The theory ain't complicated. Sometimes pulling in the wiring to cater for all the different switch locations is a tad more comlicated........

What's this "bulb" of which you speak..? A sparky once told me the difference between lamps and bulbs thusly - "lamps glow - bulbs grow"
 

Willie B

Senior Member
Joined
Jan 2, 2016
Messages
4,079
Location
Mount Tabor VT
Occupation
Electrician
The theory ain't complicated. Sometimes pulling in the wiring to cater for all the different switch locations is a tad more comlicated........

What's this "bulb" of which you speak..? A sparky once told me the difference between lamps and bulbs thusly - "lamps glow - bulbs grow"
I have to be multi lingual. A lamp, to an electrician is the component you place in a fixture. Recent code the object on your table, or ceiling is a luminaire. The thing in the wall you connect your cords to is a receptacle, as is the porcelain thing on the cellar ceiling you screw a lamp into.
Laymen do not speak the language at all, so I try to communicate. Sometimes I fail.
 

DMiller

Senior Member
Joined
Feb 21, 2010
Messages
16,724
Location
Hermann, Missouri
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Cheap "old" Geezer
240 is two 120v legs, HOWEVER, have to be separate drops from the transformer to the main bus or will not work. Most tandem breakers get one leg from each drop off a triplex feed cable.
 

Willie B

Senior Member
Joined
Jan 2, 2016
Messages
4,079
Location
Mount Tabor VT
Occupation
Electrician
At the transformer provided by your utility company you get 240 volts. For some purposes the USA & others believe you don't need 240 volts. Here we cut the sandwich in half. The transformer secondary is center tapped. We get 120 volts from either half of the transformer secondary winding.
To utilize both 120 & 240 volts we need 3 conductors.
From the transformer to your single family house you have three conductors. One conductor (the center tap) is grounded at the utility transformer & again at the service on your house.
If this is done properly, the ground includes concrete foundation reinforcing steel, any conductive materials in contact with the ground, any metal underground water supply. I'm sure I failed to mention some component. If others aren't available we add grounding electrode(s).

Everything downstream from your service disconnect needs 4 conductors & we isolate grounding from grounded. These two words sound related, but are very different. The center tap (grounded) conductor is current carrying. We do NOT want grounding conductors to carry current.

Pump Guy, I believe had a building originally supplied with a cable with two insulated conductors, enough to be code compliant for 120 volts. A dairy farmer could use his cable to derive 240 & 120 volt power, he'd brag about how dangerous it is.

The other problem Pump Guy has is cable size.

I recently learned a bit about compressor motors. It has been common knowledge many years that code numbers denote efficiency. My air compressor looks identical to the one at our volunteer fire house. Mine was bought second hand. It had come from an industrial supply. The compressor at the fire house came from Tractor Supply. When we had problems with the one at the fire house starting on utility power, & stalling a generator plenty big enough, I questioned why. I found the run capacitor was bad, replacing it helped. Then I learned the Tractor Supply compressor was supplied with same motor except code L, where mine is code G.

Code L requires 9 to 10 times full load current to start. Code G needs 5 to 6 times full load to start.
 
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