Now as for Radman’s whack at it, in general he is correct. In general.
Wires that are solid don’t put any more of a strain on a lamp than stranded ones. In fact, since solid wires in this theoretical sense kind of support themselves, they would probably put less weight or pulling pressure depending upon his meaning "straign on the lamp." Same thing with if the idea of putting strain on the lamp is in a solid
wire being worse for connectivity to the lamp than a stranded one in putting strain on it. The solid would probably put less of a strain on the lamp because it retains it’s shape. One might find solid
wire used in flash lights for instance.
The rest of the sentence is basically correct in essence - the
wire being solid would most likely not be available with a heat rated
jacket on it in the proper
wire gauge. Thus in being the wrong
insulation, pose a fire hazzard though I doubt that the
insulation would catch on fire. The
shock hazzard on the other
hand should the
insulation melt off is correct. Is this not the case often with normal
PAR cans however? That's why Kupo is selling lamp adjustment knobs and their testing lab otherwise requires a screened cap over the hole in the rear of the
fixture. I find this interesting as nobody else has to have this cap to get listed by a testing facility such as UL, but I certainly understand the necessity of it even if it does not allow for adjustment of the beam.
By the way, that fiberglass sleeved conductors is as opposed to other mulit-conductor types of cable that is rated for the temperature such as Rockbestos that would also be acceptable. Also the use of fiberglass sleeving would not exclude the use of properly heat rated conductors; it is in addition to the requirement of them and only a sleeve not a type of
wire.
Some conductors such as TGGT and SF-2 will come with a fiberglass sleeving over the individual conductors which might be argued that such
wire does not require the extra over sleeve of 0.025" thick fiberglass sleeve; but it would be incorrect unless the
conductor fiberglass over coating were of the same
thickness.
In general, these heat wires come in Teflon and Silicone
insulation and both with and without the braided fiberglass over it depending upon the style. This has no overall
effect on it’s temperature
rating as silicone coated SF-2 with and without the braiding is rated for the same temperature. I prefer fiberglass sleeved SF-2
wire because after the silicone melts, at least you still have what's left of the fiberglass coating on it protecting you, but it still melts just as easily as non-coated ones in similar applications.
Now as for the
NEC requirements cited, 520.68 talks about the
fixture cord as a supplement to Article #406 which is the
fixture cord compliance for more normal fixtures such as the ones Mayhem is using because they are probably not listed for use on the
stage. This is a rock and
roll aluminum
PAR can which arguably given Article 520.68(A)(3) would be non-Code compliant because of it’s thermoplastic SJT
cord normally in use that does not comply with the above.
Rock and
roll PAR cans instead are built around Article 406 and 410 for compliance given the differing classification of use for them. In other words, it can be argued that if your
par Can has a SJT
wire on it such as most rock and
roll store bought cans will, it cannot be listed for use on
stage. Remember that compliance for rock and
roll falls under the more
broad "Places of Assembly" classification which allows things like the use of SJ
wire when supported by the
truss instead of the normal hard service cords.
Given most of them probably are listed for
stage and studio use, the testing lab must have written off on the use of that type of
cord, or it was an overcite given this rule. This rule also has applications in saying why fiberglass sleeved wires cannot be used for a
twofer in additon to the rules against using a
plug for an interconnection device or the theater specific rules on twofers being molded and extra hard service in construction.
I'm now off my
point...
In any case, Article 520.68(A)(3) does not mention at all the connection to the lamp
base,
socket as it’s called or lamp itself. It is only talking about the
fixture whip which was not shown in the photo thus cannot be commented upon. In other words, in not mentioning the means of attachment of a lamp to the
fixture cord, it’s going to be covered in Article 410 - Luminaries (Lighting Fixtures), Lampholders and Lamps as a general covering all theater and other lights with very few exceptions such as arc lights must comply with no matter the application.
Let’s see, Article 410.3 Live Parts, this photo does comply with in that Mayhem was the one that removed the shrink tubing thus before he removed it, the
fixture was in compliance with this.
Article 410.17 also does not matter in that we are not talking about the
ground also not the subject of the photo.
What we are looking for is section VI. Wiring of Luminaries (Fixtures)
Article 410.22 and 410.24 would be the ones Radman is looking for where the question of compliance with heat is involved. It also says to see article 402 for types of suitable
wire for the wattage or heat of the
fixture.
Those of you looking for the rule on the “positive and negative” or hot and
neutral will want #410.23 and #410.42(A) which says the same thing.
Stranded
wire is 410.28(E), one might also look at (D) which sends us to Article 110.14 for the suitable means of making a splice or tap.
One will note that means of attachment of the lamp to the
conductor is not mentioned for other than screw based lamp types in a general look at the
NEC. It's probably in 110.14. In general this lack of lamp
base on a
fixture much less lamp type designed to work with one was the first thing I saw. In not mentioning a lack of lamp
base as the first and most important thing, any number of things talked about such as heat
wire, solid verses stranded, lack of solder or
crimp splice
etc. are moot.
There is also that stickler cover-all rule about “done in a professional workmen like manner” which while the wiring was neat, was not professional or what any workmen that did this type of a thing for a living would be caught doing.