al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
OK. Support that with quotes from the NEC.
California Three-ways
- Thread starter chris1971
- Start date
- Status
milehiwire
Banned
Okay, yours is a false argument. (Dang, I am glad I am not married anymore.)
310.4 Conductors in Parallel.
(A) General. Aluminum, copper-clad aluminum, or copper
conductors of size 1/0 AWG and larger, comprising each
phase, polarity, neutral, or grounded circuit conductor shall
be permitted to be connected in parallel (electrically joined
at both ends).
Exception No. 1: Conductors in sizes smaller than 1/0
AWG shall be permitted to be run in parallel to supply
control power to indicating instruments, contactors, relays,
solenoids, and similar control devices, or for frequencies of
360 Hz and higher, provided all of the following apply:
(a) They are contained within the same raceway or
cable.
(b) The ampacity of each individual conductor is sufficient
to carry the entire load current shared by the parallel
conductors.
(c) The overcurrent protection is such that the ampacity
of each individual conductor will not be exceeded if one
or more of the parallel conductors become inadvertently
disconnected.
Exception No. 2: Under engineering supervision,
grounded neutral conductors in sizes 2 AWG and larger
shall be permitted to be run in parallel for existing
installations.
FPN to Exception No. 2: Exception No. 2 can be used to
alleviate overheating of neutral conductors in existing installations
due to high content of triplen harmonic currents.
(B) Conductor Characteristics. The paralleled conductors
in each phase, polarity, neutral, grounded circuit conductor,
or equipment grounding conductor shall comply
with all of the following:
(1) Be the same length
(2) Have the same conductor material
(3) Be the same size in circular mil area
(4) Have the same insulation type
(5) Be terminated in the same manner
(C) Separate Cables or Raceways. Where run in separate
cables or raceways, the cables or raceways with conductors
shall have the same number of conductors and shall have
the same electrical characteristics. Conductors of one
phase, polarity, neutral, grounded circuit conductor, or
equipment grounding conductor shall not be required to
have the same physical characteristics as those of another
phase, polarity, neutral, grounded circuit conductor, or
equipment grounding conductor to achieve balance.
(D) Ampacity Adjustment. Conductors installed in parallel
shall comply with the provisions of 310.15(B)(2)(a).
(E) Equipment Grounding Conductors. Where parallel
equipment grounding conductors are used, they shall be
sized in accordance with 250.122. Sectioned equipment
grounding conductors smaller than 1/0 AWG shall be permitted
in multiconductor cables in accordance with 310.13,
provided the combined circular mil area in each cable complies
with 250.122.
310.4 Conductors in Parallel.
(A) General. Aluminum, copper-clad aluminum, or copper
conductors of size 1/0 AWG and larger, comprising each
phase, polarity, neutral, or grounded circuit conductor shall
be permitted to be connected in parallel (electrically joined
at both ends).
Exception No. 1: Conductors in sizes smaller than 1/0
AWG shall be permitted to be run in parallel to supply
control power to indicating instruments, contactors, relays,
solenoids, and similar control devices, or for frequencies of
360 Hz and higher, provided all of the following apply:
(a) They are contained within the same raceway or
cable.
(b) The ampacity of each individual conductor is sufficient
to carry the entire load current shared by the parallel
conductors.
(c) The overcurrent protection is such that the ampacity
of each individual conductor will not be exceeded if one
or more of the parallel conductors become inadvertently
disconnected.
Exception No. 2: Under engineering supervision,
grounded neutral conductors in sizes 2 AWG and larger
shall be permitted to be run in parallel for existing
installations.
FPN to Exception No. 2: Exception No. 2 can be used to
alleviate overheating of neutral conductors in existing installations
due to high content of triplen harmonic currents.
(B) Conductor Characteristics. The paralleled conductors
in each phase, polarity, neutral, grounded circuit conductor,
or equipment grounding conductor shall comply
with all of the following:
(1) Be the same length
(2) Have the same conductor material
(3) Be the same size in circular mil area
(4) Have the same insulation type
(5) Be terminated in the same manner
(C) Separate Cables or Raceways. Where run in separate
cables or raceways, the cables or raceways with conductors
shall have the same number of conductors and shall have
the same electrical characteristics. Conductors of one
phase, polarity, neutral, grounded circuit conductor, or
equipment grounding conductor shall not be required to
have the same physical characteristics as those of another
phase, polarity, neutral, grounded circuit conductor, or
equipment grounding conductor to achieve balance.
(D) Ampacity Adjustment. Conductors installed in parallel
shall comply with the provisions of 310.15(B)(2)(a).
(E) Equipment Grounding Conductors. Where parallel
equipment grounding conductors are used, they shall be
sized in accordance with 250.122. Sectioned equipment
grounding conductors smaller than 1/0 AWG shall be permitted
in multiconductor cables in accordance with 310.13,
provided the combined circular mil area in each cable complies
with 250.122.
al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
I get that, about your opinion about my opinion.
Your copying the total of 310.4 is a great buck shot blast, but where is the language that says that conductors that are "connected in parallel (electrically joined at both ends)" can be smaller than 1/0 when used for lighting outlets on 15 and 20 amp circuits wired with #14 and #12 conductors?
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milehiwire
Banned
Umm.... Dang. My ex was from Minnisoda.......... (Shudders with happy relief.)
Show me where the conductors are in "parallel"? Any more than any three-way carrying a hot and switch leg.
Show me where the conductors are in "parallel"? Any more than any three-way carrying a hot and switch leg.
al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
In this diagram, the outlets that the California 3 way control are OFF. As the benefit of the switching setup is that it supplies unswitched power to outlets downstream, for the purpose of illustration, I place a 10 Amp load. Current A and Current B are the parallel currents.
milehiwire
Banned
In this diagram, the outlets that the California 3 way control are OFF. As the benefit of the switching setup is that it supplies unswitched power to outlets downstream, for the purpose of illustration, I place a 10 Amp load. Current A and Current B are the parallel currents.
Ummmmmm....... Oh, once you put a load off of the right hand switch..... I like my crow slow roasted and smoked in a bbq................
jmellc
Senior Member
- Location
- Durham, NC
- Occupation
- Facility Maintenance Tech. Licensed Electrician
Never seen one, had a friend who'd seen them and referred to them as Hollywood 3 ways. Looks hazardous, as in some positions, light is receiving power but not neutral. One would think no power, but get lit up handling it if grounded.
- Status