Originally Posted by escape artist
Hi: Iowa Dave... When doing the kitchen reno I had a new breaker panel put in and a 30 Amp RV receptacle put in the garage. All I know is the wire heading out there is orange. The wire to the kitchen receptacles is yellow, and all the rest of the wiring is white. That's as scientific as it gets. Alf
escape artist N.S. of Lake Erie
The NEC requires that NM ( Romex ) cable be color coded according to the AWG size of the conductors .
The cable's outer jacket is color coded -- white , yellow , orange
White NM = #14 AWG -- 15 amp
Yellow NM = #12 AWG -- 20 amp
Orange NM = #10 AWG - 30 amp
Color coding helps insure that the proper size NM cable is installed and makes it easier for the inspector to be sure that the proper size wire was installed
#14 AWG Copper is used for general lighting and receptacles circuits in residential construction.
#12 AWG Copper is used for kitchen appliance , dining room , pantry , laundry , bath room receptacle and rec room circuits.
#10 AWG Copper or #8 AWG Alum is used for dryer , electric water heater , central A/C , cooktops and special purpose circuits
#8 AWG Copper or #6 AWG Alum is used for ranges and oven circuits
#6 AWG Copper is used for double ovens.
* Some appliances and equipment are not UL listed for use with aluminum conductors.*
**Aluminum Romex was used in residences and mobile homes back in the 70's and it created a huge amount of problems .
The receptacles were not rated for aluminum wire which led to terminations burning off and fires. The use of aluminum conductors has been limited by the NEC **
*** #14 AWG wire is normally used in residential construction for general branch circuit wiring.
#12 AWG is the standard in commercial and industrial construction for branch circuit wiring.***
**** #14 AWG Copper wire is the minimum size wire for building wiring except in the case of signal or control circuits ****
***** The size of the wire must be sufficient for the load being served . You can use a larger conductor than required by code .
IE , You could use #12 AWG wire for general lighting circuits in a residence instead of #14 but many inspectors would still require you to use a 15 amp overcurrent device to protect the circuit.