Why do you suppose the Black conductor was spared the fate of the Red and the White?

These were the conductors between the weatherhead and the aerial drop on a 100 Amp resi service.

Black pigment provided better UV protection?

I'd agree with NJwirenut...light coloured plastics deteriorate very quickly under UV (sun or flouro light). You can see the plastic has become brittle and cracked where the wire has been bent back out of its original shape.

How old is it? I haven't seen a 100 amp service on a residence in decades, even old ones. I would guess that it's at least 40 years old, correct? If so, I would imagine that anything exposed to the sun for that long would fade, just like our skin!

I imagine that, if they were color-coded conductors at all, that they were not SE rated, and certainly not UV rated.

I don't think I've ever seen colored SE conductors out in the sun here in Cali at all. Always black with some phasing tape on the neutral.

As far as 100A service to a resi, I see them all the time out here.

Between the PoCo drop, going into the weatherhead? Probably installed by a contractor, then.

I'm not sure we're looking at sun damage. I've seen many an instance of the colors fading, while the base plastic remained just fine.

Out here, there was a firm selling wire that was not UV resistant at all; the PoCo ran miles and miles of it. Now, the PoCo get to replace it all - and the maker is nowhere to be found. Here is a pic of the substandard wire:




I don't see that sort of 'alligator skin' damage to the insulation. Could the insulation have been damaged by something rubbing against it?

EV607797,
The service was a Zinsco "all-in-one" with some (about 50%) GTE/Sylvania breakers in it. Zinsco was sold to GTE/Sylvania in 1973. I don't know any more than that.
There's lots of 100 Amp services here on the West Coast.


Reno,
The alligator skin is there alright, but it goes all the way around the red and the white. The black has it to a lesser degree, and it doesn't show any effect to the area not in direct sunlight. There is an old pepper tree overhanging the roof.




No smog jokes

I installed some 4/0 AL SEU cable like that about seven years ago for a customer who wanted to supply her own materials. She got it from Home Depot. It had one black conductor and one red conductor. For residential single-phase, WHY?
After a few months in the sun, at the weather head, the black conductor looked fine but the red conductor had turned pink. About a year later, I saw it again and by then, it had turned a pale pinkish-white. I can just imagine what it looks like now.
I know the code says that SE cables don’t need to be rated UV resistant when exposed for connection at the service drop, but why even make crap like that?

Zinsco......Thank goodness that cancer didn't spread much to the east coast! They existed here, but not for long. No offense intended about the 100A services, probably due to lower heating loads in your parts. We do see them here, but rarely on a residence that's less than 40 years old.

I will say that I've seen some THHN/THWN that was either black or white as far as the base insulation color and the nylon outer covering provided the actual coloring. I remember that red was usually white underneath the nylon. I think that I saw blue and green done the same way. I guess that manufacturers saved money by NOT adding pigment to the base conductor insulation and just coloring it on the outside.

There was a time when you could actually specify THHN or THWN, but not anymore. All you will ever see today is a combo. Maybe what you saw was THHN from the 1960's?

Sunlight will do quite a job on anything. The outer nylon jacket cracks, exposing the underlying base color.

I agree about the black/red question. In single phase, what difference does it make? If phasing really mattered, shouldn't it be a black and a red for one job, a red and a blue for another and a blue and a black for the third? It's just silly. Aside from troubleshooting purposes, I don't see the need to color the legs.

I'm sure that the red conductor you saw was just painted onto a black XHHW conductor. I remember it....It looked like someone was just standing there with a red paint brush as the black cable came out of the assembly line. Nowadays, it's just a red racing stripe at best. I am simply delighted with the new 6/3 Romex where all conductors are black with colored stripes. I know that the manufacturers are doing this to save money, but man those stripes are hard to see when terminating on a surface-mount range receptacle where you don't have a lot of slack.

Then on the other hand, while a certain manufacturer thinks that #6 Romex and above can use racing stripes on black, they are marketing colored 4/0+ in all colors? I must be missing something.

THHN in the 1960's????? From what I understand it was rolled out in the 70's .

Could be. My first exposure to it was in 1972.

We had worked with one of the cable manufacturers once for some specialty cable. The UV inhibitors they used in the thermoset jacket were all black, which was a large part of why most (all?) of the cables they sold had black outer jackets; the catch when requesting color-coded jackets was the cables lost their UV resistance.

It must be a regional thing. 100 amp services are extremely common in New England on homes of any time period, and are sill installed on a good percentage of small new homes with gas/oil heat.

100-amp services are the norm here for new homes, unless a larger supply is requested for some specific reason (2-wire with everything running on 240V, of course).

There are still plenty of older 60A services around, a few 40A, and even on odd 30A.

Peter:

Yeah, I suppose it is a regional thing. 200 amp is pretty much the norm around here for residential, but 300 & 400 are becoming quite common. There are plenty of 100's around here, but only on very old homes, as in 1950's or earlier.

Then again, about 50+% of the homes my in area use electric heat. I guess that would explain it.

A lot of homes around here have electric heat as well (I'm one of them), but still only with 100A supplies. Of course, our homes are smaller on average, with 1500 sq. ft. being considered spacious.

If I have all my storage heaters switched on, it throws a total load of about 14kW (~58 amps) on the service when the contactor closes around midnight.

The last two residential services I did here in coastal Southern CA. were overhead 100A.
And the only U/V protected/sunlight resistant stuff was Black TWHN. The other colors did not have the Listing. So, as Zapped said,
use Black, and white tape the neutral.

We upgraded my grandfather's house in 1991, black THWN, and it's still OK. (Again, coastal CA. - lots of 75° sunshine, little rain.)

This stuff was THW, remember THWN was a newfangled type. We (my shop) used TW or THW right up until '78 or '79.

The color was all the way through the conductor.

(I replaced it with Cu THWN, all black conductors, neut taped white)

Paul, please elaborate on the "contactor closing around midnight". Is that some kind of energy management program?

My house is about 3,000 SF, so my electrical requirement would be expected to be twice of yours, but we have a heat pump that does a pretty good job of keeping us warm. Resistance heating (backup) only kicks in when it gets below freezing here.

Talk about a hijack of an original thread. I have turned this thread into a completely different subject. Sorry!

I just built a 2000 square foot edition (1500 square feet of it heated, rest is the garage), and happen to have the BTU loss calcs handy. Dropping the thermostat by 3°F would reduce heating loss by about 700 BTU/hr (200W of heating). For a heat pump with a COP of 3-4x, that's about 60W at the meter. Saving, maybe, $1 a month to drop the temp overnight while you're sleeping My thermostats are the smart electronic kind so I have them programmed to drop the temp 2° at night anyhow.

Ego te absolvo. I'd like to know more also.

I think Paul was referring to his Night-rate supply.
Heaters are switched on overnight via a contactor and are allowed to heat up (these are storage heaters with blocks of stone(?)in them to hold the heat) and are switched off again in the morning (usually about 7 or 8am), by the PoCo.
Power is cheaper on Night rate supply.

As Mike has outlined, it's the "Economy 7" tariff, which is fairly common here for electrically heated homes.

We have a dual-rate meter (i.e. two sets of dials, selected by a small solenoid, or a modern electronic equivalent), and a timeclock switches the meter over to the cheaper rate for 7 hours each night (hence the "Economy 7" name). It runs midnight thru 7 a.m. winter, 1 a.m. thru 8 a.m. in summer.

At the moment, my rates are 10.31 pence per kW/h day rate and 4.65 pence night rate, so well under half price.

As well as switching the meter to night rate, the timeclock also energizes a contactor which supplies power to a completely separate distribution panel for the storage heaters. Again, as Mike said, these contain elements inside thermal bricks so that they are "charged" with heat overnight at the low rate. A thermostatic damper control then allows that stored heat to be radiated during the day.

Same systems are used in New Zealand with ripple or pilot control to switch on or off, fixed wired appliances like storage heaters and hotwater cylinders on a cheaper rate via a contactor in the meter box.

The kWh meter has two dials which are controlled via a timeclock or ripple control.

The difference between the tarifs used to be great, (half price for nite rate ). Unfortunately with the greed of POCO's it is hardly worth while anymore and the difference between day and night rate is less than a cent difference.

Most domestic supplies are rated at 63 or 80 Ampères, single phase at 230 Volts, for an average of 1200 to 1500 sq ft houses.

"sunlight resistant" is just that - resistant, not "proof"

I have seen UV burn through UF cable that was labeled sunlight resistant.