#14awg travelers in 20A OCPD

M

marcosgue

Senior Member
Location
Tampa
Occupation
Electrician
This's commercial building for brand new emergency switchgear, the room have 4 doors. The lighting control is setting by 3W and 4W system right next to each door. The electrician ran #14awg for travelers between switches devices and the rating of the circuit is 20A breaker. Is this correct?
 
Even if this isn't a residential enviroment and isn't possibility to add any cord and plug conected load in the circuit?
 
marcosgue said:
This's commercial building for brand new emergency switchgear, the room have 4 doors. The lighting control is setting by 3W and 4W system right next to each door. The electrician ran #14awg for travelers between switches devices and the rating of the circuit is 20A breaker. Is this correct?
Click to expand...
Is these conventional 3 way and 4 way switches carrying the load of the lighting it controls or is it a control circuit that only powers a lighting relay of some kind? The latter could possibly be acceptable.
 
CoolWill said:
Not compliant. Not really unsafe, but still not compliant.
Click to expand...
If the main purpose of the Code is "the practical safeguarding of persons and property from hazards arising from the use of electricity" I think the use of inadequate ocpd in this case is also unsafe, beside not compliant
 
marcosgue said:
If the main purpose of the Code is "the practical safeguarding of persons and property from hazards arising from the use of electricity" I think the use of inadequate ocpd in this case is also unsafe, beside not compliant
Click to expand...
In general, but not in every case. This is one of those cases where it isn't really dangerous. 20 amps on a #14 will just be warm and a short circuit will still trip the breaker. It isn't compliant and I'm not endorsing it. I'm just saying that it isn't going to erupt into flames... In this case.
 
CoolWill said:
In general, but not in every case. This is one of those cases where it isn't really dangerous. 20 amps on a #14 will just be warm and a short circuit will still trip the breaker. It isn't compliant and I'm not endorsing it. I'm just saying that it isn't going to erupt into flames... In this case.
Click to expand...
And I like to point out the ampacity of #14 per the standard ampacity table is 20 amps. It's the small conductor rule that affects #14,12, and 10 conductors in 240.4 D that reduces it to 15 amps. Not sure if anybody really knows the justification for this. If it's romex, yes article 334 requires it to be sized per the 60° column, but the insulation is actually rated for 90, and I'm not sure if anybody knows the justification for that either.
 
I don't think it was ever allowed by Code but back when I was a young pup (I think Edison might have still been wiring :))it was an acceptable wiring method in some areas. When I first started inspecting there were a few "old timers" still doing so.
 
augie47 said:
I don't think it was ever allowed by Code but back when I was a young pup (I think Edison might have still been wiring :))it was an acceptable wiring method in some areas. When I first started inspecting there were a few "old timers" still doing so.
Click to expand...
I admit to the crime of sometimes using #14 MC on 20A circuits for commercial lighting. A lot of the LED troffers have real annoyingly small j boxes, and sometimes you need a little more length than a 6 ft whip offers. I do a little code extrapolation figuring if a 6 ft whip is good with 18 gauge conductors, then a 15 ft whip is probably fine with 14 gauge 😇
 
In part 3 of article334.30. 334.112 insulation . The conductor in NM shell be rated at 90C , that makes #14 good for 25 amps. I see why the switches legs would be ok.
 
guschash said:
In part 3 of article334.30. 334.112 insulation . The conductor in NM shell be rated at 90C , that makes #14 good for 25 amps. I see why the switches legs would be ok.
Click to expand...
You're refering to NM sheated cable commomly named romex but what about using single conductor thhn #14 in the original post
 
electrofelon said:
A lot of the LED troffers have real annoyingly small j boxes, and sometimes you need a little more length than a 6 ft whip offers. I do a little code extrapolation figuring if a 6 ft whip is good with 18 gauge conductors, then a 15 ft whip is probably fine with 14 gauge 😇
Click to expand...
I'd say a 'fixture whip' is after the 'lighting outlet' and not part of the 'branch circuit' but a switch leg is part of the branch circuit.
augie47 said:
I don't think it was ever allowed by Code but back when I was a young pup (I think Edison might have still been wiring :))it was an acceptable wiring method in some areas. When I first started inspecting there were a few "old timers" still doing so.
Click to expand...
In the old days they might have plumbed the wiring more as voltage drop was a bigger issue, so when we see #12 and 14 mixed in old work it likely was still was intended to be on a 15A OCPD.
If they upsized to #12 for voltage drop or whatever then used #14 for a switch leg, the code (Rule 2121 1937 NEC) required permanently connected lampholders of the medium, intermediate or candelabra type to be protected by not over 15 amps OCPD until the1940 NEC when they started to allow a medium base 'keyless' lampholder to be on a 20A branch circuit.

If you go back even farther to the 1920's they limited lighting circuits to 10 amps Rule 807(f) of the 1925 NEC , so 15A was a big upgrade in the 1930's.
I found it kinda funny that they brought back 10A lighting branch circuits exactly 100 years later.
 
You must log in or register to reply here.
Top