I am at an early stage in my electrician career and also think ns may recognize the answer to this but just desire to reach out and also get some opinions. I am adding and wiring some cables lights that ns am tieing in to existing switch legs. If the move leg to where I'm tieing in is 14/2 should I run the lights in 14/2 or should I go to breaker to make certain it's a 15 amp and also not a 20amp breaker. I say if the breaker the lights are on is 15 amp i wire v 14/2 if the breaker the lights are on room 20amp use 12/2 ???any suggestions additionally am running brand-new switch leg from brand-new fan box to present switch v power what should I use ? 14/2 or 12/2 it's a 1 gang switch tied to a outlet now. Thanks in advance!


*

14 AWG only for 15amp. 12 AWG have the right to be 15amp or at most 20 amp. Bright is frequently 14 AWG in residential. 12 AWG is typically used because that bathroom and also kitchen (garage and a pair of various other places) receptacles.

You are watching: 12 2 vs 14 2 romex


Ok cool. One various other question. If I'm putting a brand-new fan box in due to the fact that existing move is tied to outlet.. Need to I operation 14/2 it's a single switch therefore no different for fan and also light prefer 14/3


Not one electrician yet if there's 14/2 in the circuit anywhere, then the breaker must be 15a, and needs to be changed it is 20a. If the breaker is 15a then you have the right to use one of two people of 14 or 12ga wiring yet 14 will certainly be cheaper and easier to job-related with.


Supposedly there's a rule in NEC that forbids surroundings of wire smaller than the to i m sorry it's interconnecting even if the breaker is sized for the smaller sized wiring, however I don't have the quote handy. Native that suggest of view, girlfriend should constantly match what's over there (and make sure it's protected by an ideal OCPD). Various other than that, if it's a 20A circuit, usage #12, and if it's a 15A use #14.

See more: How Many Inches Are 18 Millimeters Is How Many Inches Are 18 Millimeters

In new construction, I'm fond of placing lights on different circuits indigenous receps also in residential even though it's a bit uncommon. This lets you have 12AWG and 20A receptacle circuits however have 14AWG in switch boxes i beg your pardon is means easier to job-related with, and modern LED lighting lots are sufficiently "light" that it's no a big deal to be on a 15A breaker. You additionally don't have concerns with lights dimming through vacuum cleaners, etc. The way, but it will expense you a couple extra circuits throughout the home compared to the normal approach of placing all the lights and receps for a offered area on the very same circuit.