Knob and tube wiring

[Speedskater]

I wonder what percentage of us have actually used the individual wires from NM-B inside a junction or outlet box?
I would guess over 80 %.

 

[tortuga]

Yes they do, but most of the time it is not MARKED as THHN

I might be mistaken but my understanding is somebody spent allot of time and money lobbying changes into UL 719 that save the manufacturers a tiny fraction of a cent per 1000/ft or something. There is a table in UL 719 I think section 4.4 and the conductors definitely don't need to meet the entire UL standard (83?) for THHN,
They need to be "electrically similar" but they stop short of requiring the THHN to meet UL 83 (or whatever). Note most THHN sold on spools is also THWN-2 and NM-B is dry locations only.

 

[LarryFine]

My biggest NM pet peeve is that #s 8 and 6 NM both still come in black, the jacket is printed with dots, and the numbers 8 and 6 are hard enough to tell apart when they're new, much less after they're worn from handling.

 

[JohnE]

My biggest NM pet peeve is that #s 8 and 6 NM both still come in black, the jacket is printed with dots, and the numbers 8 and 6 are hard enough to tell apart when they're new, much less after they're worn from handling.

I wish they were all black still.....14 - #6. While I'd like to think I could always get it right "by feel" my laser eye surgery has been a huge asset in the past 6 months....

 

[JohnE]

I wonder what percentage of us have actually used the individual wires from NM-B inside a junction or outlet box?
I would guess over 80 %.

I'd guess 100% of those of us who have used NM-B at all.

 

[garbo]

That must have been the last days of cloth Romex. I never saw any new rolls of it. When I started in 1976, plastic was the only option. It also had TW conductors. I left the trade a few years later, came back to it in 1995 and by then it had THHN conductors. Big improvement. 2002 or 2003, jacket colors came along. I liked that a lot too. # 10 was always easy to ID but 12 & 14 a little harder. Stiffness varied brand to brand, easy to grab the wrong roll. Colors simplify things a bit and I like that.

I believe that the newest type of Romex called NM-B cable came out in early 1980's with the thinner but way superior insulation that looks like type THHN insulation. We were told that the older style with type TW insulation had problems in hot attics down South. Color on the outer insulation was a great move. Interested in how they are coloring the outer jacket on the aluminum NM-B B cable with the 10% outer coating of copper. Think the #10 guage AL/CU cable will be rated for 25 amps. Can see Johnnie homeowner picking up a roll of 12/2 aluminum NM-B cable that is only rated for amps and placing it on 20 amp circuit breakers.

 

[letgomywago]

I believe that the newest type of Romex called NM-B cable came out in early 1980's with the thinner but way superior insulation that looks like type THHN insulation. We were told that the older style with type TW insulation had problems in hot attics down South. Color on the outer insulation was a great move. Interested in how they are coloring the outer jacket on the aluminum NM-B B cable with the 10% outer coating of copper. Think the #10 guage AL/CU cable will be rated for 25 amps. Can see Johnnie homeowner picking up a roll of 12/2 aluminum NM-B cable that is only rated for amps and placing it on 20 amp circuit breakers.

The one that's starting to be more available uses yellow for 10awg and white for 12 so that the ampacity of the wire is for the most part the same.

 

[norcal]

There was a earlier effort to color code romex I remember #14 with a light blue jacket and #12 with a black jacket do you remember that stuff?
Unless I am mistaken they don't really use actual "THHN" in the romex today, with the old romex really had "TW" it was printed on the conductor.

Have seen 12/2 NM that had a light blue sheathing, it was made by Phelps-Dodge & the time that part of the building was constructed was 1968, also had the reduced size grounding conductor.

 

[jmellc]

I believe that the newest type of Romex called NM-B cable came out in early 1980's with the thinner but way superior insulation that looks like type THHN insulation. We were told that the older style with type TW insulation had problems in hot attics down South. Color on the outer insulation was a great move. Interested in how they are coloring the outer jacket on the aluminum NM-B B cable with the 10% outer coating of copper. Think the #10 guage AL/CU cable will be rated for 25 amps. Can see Johnnie homeowner picking up a roll of 12/2 aluminum NM-B cable that is only rated for amps and placing it on 20 amp circuit breakers.

So we have aluminum Romex again? First I’ve heard of that. Not a good thing IMHO. I think AL is fine for services & larger circuits like range & HVAC but not good for lights & receptacles. Too hard to pack into small boxes. A pain to have to use expensive AL wire nuts too.

 

[jmellc]

In the mid and late 80's here romex came in black and white. No size relation 12/2, 14/2, 14/3, 10/2, 10/3 came in both colors. (I didn't pay close attention, it was probably based on manufacturer. It was also boxed in 250' coils, not plastic wrapped.) I do remember light blue 14/2 from earlier days, and I assumed it was just one mfg's choice. UF used to come in white or black, not gray. I hated when the white/ yellow/ orange colors came in the early 2000's. I liked the all white scheme. I also liked when the Arlington Black Buttons were white....

UF was always grey that I saw. About 2018, I saw some in white for the first time. 12-2.