Origin of '3-way' and '4-way' terms?

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480sparky

480sparky

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I don't think I've ever seen a definitive answer to the question "Where did 3-way and 4-way switches get their names from?" I've heard plenty of theories, many plausable, some not.

But I just got an Arrow wiring devices catalog, quite old, but no date is given. Only information is "Catalog No. 22". There's a business card inside dated 1937.

In it, there are these wiring diagrams for 3-ways and 4-ways. Rather, 3-point and 4-point:

3ways4waysname.jpg
 
So it's always had to do with the size of the switch, not it's function :D

Roger
 
That was one of the first question I ask back in 1980 when I became an apprentice. The first way to turn off a light in the circuit is to unscrew the bulb and flip a single pole switch is "Two ways"
If you want to turn it off from three different points, you replace the single pole with a three-way and add a second three-way with two traveler wires.
After that you can turn it off from as many points as you want by adding four ways switches in between the traveler's.
And of course if you think the entire length of this lighting circuitry will exceed 60 feet, you'll need to use 12 gage wire, because 14 gage will have voltage drop after 60 feet.
Because of voltage-drop, its quite common to see 12 gage wire on a 15 amp breaker in a residential setting.
 
David C. Adkins said:
Because of voltage-drop, its quite common to see 12 gage wire on a 15 amp breaker in a residential setting.
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I believe you will find that is not common in most of the country.

Besides the fact the voltage drop is directly related to the amount of current and typical 3 way switching in a dwelling unit will not be switching much more then a few amps if that much.
 
No I wouldn't use 12 gage on the entire 15 amp circuit,that swithed light isn't all that is on that circuit, based on the length of the circuit, maybe just the home run. Voltage-drop is resistance and every spliced outlet on a circuit adds resistance to the 60 foot rule for 14 gage. We could also install some three and four way dimmer switches for more resistance and today's 60 watt mushroom ceiling fixture might be tomorrows 360 watt chandelier. I've all way made my 15 amp home-runs in new houses with 12 gage unless the house was a small bungalow with no internal distance to travel; up and down and over and back !

Not to change the subject but I've seen voltage coming into Homes at 110/220 volts on cloth covered individual utility drops ( # 8 solid copper-clad) (Not- triplex) I've tied services up to those small undersized drops, after a call from an inspector to release to the service to the utility company and years latter, the very same under sized service drops will usually remain. And why not, why would a utility company want to upgrade the drop and make the meter spin slower.
 
David C. Adkins said:
No I wouldn't use 12 gage on the entire 15 amp circuit,that swithed light isn't all that is on that circuit, based on the length of the circuit, maybe just the home run. Voltage-drop is resistance and every spliced outlet on a circuit adds resistance to the 60 foot rule for 14 gage. We could also install some three and four way dimmer switches for more resistance and today's 60 watt mushroom ceiling fixture might be tomorrows 360 watt chandelier. I've all way made my 15 amp home-runs in new houses with 12 gage unless the house was a small bungalow with no internal distance to travel; up and down and over and back !
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I have never heard of a 60ft rule with 14awg. Voltalge Drop depends on the load.
 
David C. Adkins said:
Not to change the subject but I've seen voltage coming into Homes at 110/220 volts on cloth covered individual utility drops ( # 8 solid copper-clad) (Not- triplex) I've tied services up to those small undersized drops, after a call from an inspector to release to the service to the utility company and years latter, the very same under sized service drops will usually remain. And why not, why would a utility company want to upgrade the drop and make the meter spin slower.
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David if there is utility company voltage drop due to small service conductors it will not raise the homeowners bill. The meter records watts not amps.

Now if the voltage drop is on the customer side the customer ends up paying to heat up those branch circuit conductors.
 
Back to the point, 3 point and 4 point designation makes senses. They are not 3 pole or 4 pole. Somehow the terms got misplaced.

The NEC does use the term 3 way and 4 way in 200.7 C 2. Who has an old code book and can go back and see when this was added?
 
tom baker said:
Back to the point, 3 point and 4 point designation makes senses. They are not 3 pole or 4 pole. Somehow the terms got misplaced.

The NEC does use the term 3 way and 4 way in 200.7 C 2. Who has an old code book and can go back and see when this was added?
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1940 is the first use of 3-way and 4-way in (what becomes) that section.

2006 Identified conductors in Identified Circuits Only
b.Cable containing an identified conductor may be used for single-pole, three-way or four-way switch loops if the connections are so made that the unidentified conductor is the return conductor from the switch to the outlet.
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Unidentified is the ungrounded (hot) today, and identified is the grounded (neutral / white).


Minuteman said:
I always thought, that the terms 3 or 4 way (points) came from the fact that there are 3 or 4 terminals and thus 3 or 4 places to attach wire.
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Then a DPST switch could also be a 4-way.
 
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David C. Adkins said:
...60 foot rule for 14 gage.
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David, you really need to walk softly when speaking of your preferred installation practices as "rules." You're going to run the gauntlet when you make comments like that. :)

David C. Adkins said:
We could also install some three and four way dimmer switches for more resistance
Click to expand...
Do dimmer switches add resistance to a circuit?
 
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