2023 310.3 Conductors

[@brianerock]

The reason that CCA conductors, unlike UNinsulated/PREinsulated CU and AL conductors, absolutely MUST be Listed is that those of us on NEC® Correlating Committee’s CCA Task Group who represent manufacturers of products (e.g., receptacles, switches, circuit breakers, fuse holders, etc.) that TERMINATE on the CCA wanted assurances via Listing that: • not only 10% CU by cross-sectional AREA but also assurance of both MIN THICKNESS CU and »MIN AVERAGE THICKNESS« CU over the aluminum substrate • CU is METALLURGICALLY bonded to AL, so that the CU absolutely CANNOT delaminate from the AL (CU absolutely CANNOT be merely a plating or a flash) • Given the prevalence of fraudulent, counterfeit “CCA” from the Far East, assurances via independent (3rd-party certification = Listing), continuing production audits that the CCA conductors, insulated or (for EGC) bare, was in fact truly compliant CCA. None of us who manufacture terminating devices want the liability litigation associated with UNlistable, fraudulent “CCA”.

[@mattv5281]

Plain aluminum is allowed with the same size as CCA, so 10% copper seems like overkill. Gold plated connectors for low voltage typically have a layer of gold measured in microns, and it does the job.

[@dirtavalanche7182]

I don't see stranded Type USE or USE-2 listed in 310.3(B) as being required to be AA-800 series. So I infer that a USE-2 4/0 stranded AA 1350 Aluminum conductor may be used in an outdoor feeder. Is that correct?

[@Sparky-ww5re]

Whether you live in an home or apartment, if it was built after 1960, it's almost guaranteed to contain some aluminum wiring. From the mid 1970s-present, aluminum is super common for the service wires down to the meter and feeding the main panel, subpanel feeders, and large 240V circuits for the dryer, range, or central air conditioner/electric furnace. From 1965-1973 give or take a few years, aluminum for the 15 and 20 amp general purpose circuits was used almost exclusively, and it was the AL 1350 series prior to 1972. The many problems caused by this wiring is what gave AL a bad reputation.

[@PillarsOfHeaven]

Interesting. What resources do you recommend for that?

[@Sparky-ww5re]

@@PillarsOfHeaven For repairing old aluminum single strand wiring I prefer pigtailing with Alumniconn connectors because they are widely accepted as a permanent repair. Less expensive are CO/ALR rated receptacles and switches, I don't prefer these because looping the conductors around the terminals sometimes causes them to snap because aluminum tends to become brittle after 50 years. On the other hand using Alumniconn sometimes requires a larger outlet box particularly if installing a dimmer or GFCI receptacle because the boxes from the era of aluminum wiring were often metal boxes smaller than the plastic boxes commonly used today, for this reason I keep plenty of rework boxes in my service truck if I'm repairing aluminum wiring.

[@KLAWNINETY]

It really depends on your area. In my area in the midwest most homes do not have any AL wiring, including new construction homes. I'm not sure if it's because they don't want to increase the size of the feeder pipe or it's just not enough length for AL to save money on the service conductors. If the meter was on a separate pole and you had out buildings the AL would be a lot cheaper. I feel like it's really worth it to use it when you have to upsize the wire for voltage drop anyway but you better have a tugger because for a given ampacity AL is always harder to pull because the conductors are so much larger (even though the AL is LIGHTER for a given ampacity than CU which is why overhead conductors are always AL)

[@hologonxyz]

INFORMATIVE!

[@Ariccio123]

I dunno, as someone currently dealing with really severe home electrical problems that are due to some combination of all aluminum busbars in the outdoor meter panel + main breaker, and also the all aluminum 4/0 service entry cable. I'd *really* appreciate it if they made it code to use CCA wherever they would previously used plain aluminum

[@brianerock]

FWIW, 14 AWG CCA in fact DOES appear in the 2023 NEC®, specifically added as NEW 240.4(D)(3) [other list items RENUMBERED editorially] and in Table 210.24(A)(2).

[@jorgehuizarsr8519]

I don’t like changes every 3 years 😖😖