mbrooke
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Are the conductors in a California (key word) 3 way required to all be counted as current carrying?
3 way current carrying conductor
- Thread starter mbrooke
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al hildenbrand
Senior Member
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- Minnesota
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- Electrical Contractor, Electrical Consultant, Electrical Engineer
There is one instance of switch positions that results in ALL four conductors carrying the switched load current, so, Yes.
luckylerado
Senior Member
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- Lake of the Ozarks
It is not going to change conductor size very often because in most cases you will be starting with the ampacity listed in the 90?C column.
- Location
- Massachusetts
What is that and is it a legal method anyway?
electricalist
Senior Member
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- dallas tx
yes if its a branch circuit. No if its part of a mwbc.
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- Placerville, CA, USA
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- Retired PV System Designer
The circuit which switches only the hot is compliant. The version which switches the neutral is not.
Which one is the California 3-way and what is the other one called?
Chicago?
Which one is the California 3-way and what is the other one called?
Chicago?
al hildenbrand
Senior Member
- Location
- Minnesota
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- Electrical Contractor, Electrical Consultant, Electrical Engineer
Ken,
While there is no definitive reference we can point to for the naming convention, I believe the most common names for the circuit you posted in your post is a "farmer", "Carter" or "Chicago" threeway, that is distinguished by polarity reversal in the lampholder.
The OP is, in the name "California" threeway, asking about another threeway configuration, until he tells us otherwise, distinguished by a conductor that bonds the Common terminal of one threeway switch to the other Common terminal of the other threeway switch, and does nothing else, and the Common terminals have no other connections.
While there is no definitive reference we can point to for the naming convention, I believe the most common names for the circuit you posted in your post is a "farmer", "Carter" or "Chicago" threeway, that is distinguished by polarity reversal in the lampholder.
The OP is, in the name "California" threeway, asking about another threeway configuration, until he tells us otherwise, distinguished by a conductor that bonds the Common terminal of one threeway switch to the other Common terminal of the other threeway switch, and does nothing else, and the Common terminals have no other connections.
electricalist
Senior Member
- Location
- dallas tx
Wiki shows California 3 way as no switched neutral, but says the Carter ,farmer 3 way is switched neutral and in 1923 banned by the NEC.
mbrooke
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http://www.act-solutions.com/PCC/images/fig5.gif
Looks legal to me?
My concern is that under the right condition all 4 wires will carry current?
al hildenbrand
Senior Member
- Location
- Minnesota
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- Electrical Contractor, Electrical Consultant, Electrical Engineer
Looks legal to me?
Some, here, have argued that, when the hot conductor continues on past the end threeway switch to supply unswitched load, AND the two threeway switches are in the position shown in the diagram, that the current is split between two parallel conductors, and that 310.10(H) says that can only be done when the conductors are 1/0 and larger.
mbrooke
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True, but the intention inst to parallel, rather an inadvertent byproduct?
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- Placerville, CA, USA
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- Retired PV System Designer
Note also that in the diagram shown the conductors are only in parallel when they are carrying no current.
Finally, nowhere do you have single lengths of conductor connecting the same two endpoints directly.
Once you put the switch in the middle, you do not have parallel conductors.
The same argument has been applied to a manual bypass switch around a photocell, and I do not thing the parallel conductor rules apply there either.
The intent of the rule, FWIW, is the use of multiple conductors to increase the ampacity of the circuit.
mbrooke
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- United States
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My thoughts, I do not believe this constitutes the intent of parallel conductors.
Now, correct to assume that in the right position all 4 wires will carry the load with added voltage drop as well?
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- Placerville, CA, USA
- Occupation
- Retired PV System Designer
In the diagram shown (Coast 3-way) no cross section of the circuit has more than 3 wires. And in the center section all three will be counted as CCCs.
If you combine several runs of that diagram into one raceway, then you could have more than four.
John120/240
Senior Member
- Location
- Olathe, Kansas
Before 14-2-2 Romex we would borrow the white wire & common name was California 3 Way. Let me try to explain: One coach light at front door. Coach light at garage overhead door. 3 way between front door & inside garage with power at front door. Send the front door switch leg to garage on the white of 14-3 with red/black travelers.
At front door & inside garage there was always a two gang switch box where you could pick up neutral. You had to keep all of it on the same circuit.
At front door & inside garage there was always a two gang switch box where you could pick up neutral. You had to keep all of it on the same circuit.
- Occupation
- Licensed Electrician
That is a slight variation on a California three way but meets the same criteria of current on one wire with no opposing current to balance the circuit. What I have always known as a California three way is also known as California travelers, hot in one box, switch leg in the other, 14-2 or 12-2 romex for your travelers.
They will do anything they can out in California to save $2 worth of wire so that by the time you build 200,000 houses in a month you might make some money.
- Location
- Massachusetts
The funny thing is none of my inspectors seem to care what mbrooke on the Internet feels the intent is.
Right or wrong it is IMO a violation.
mbrooke
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- United States
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- Technician
The funny thing is none of my inspectors seem to care what mbrooke on the Internet feels the intent is.
Right or wrong it is IMO a violation.
But the conductors aren't parallel while they are carrying current. And, if that was the true intent of the parallel conductor rule I can think of over a dozen scenarios used every day (UPS/timer bypass as one example) that would be illegal. You may feel it is a violation, and it might be depending on interpretation, but nothing explicitly prohibits it.
al hildenbrand
Senior Member
- Location
- Minnesota
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- Electrical Contractor, Electrical Consultant, Electrical Engineer
???? Again. Look at the Fig. 5 that you posted. The top "traveler" black wire is the continuous hot. If that hot is extended beyond the end threeway switch to any more load, that load current will travel in parallel conductors when the switches are in the exact position shown in the Fig. 5 photo in this thread.
but nothing explicitly prohibits it.
Are the parallel conductors compliant with the language of 310.10(H)? If the conductors are #12 or #14, they are not compliant. They are prohibited.
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