Told yah he would know.
The man knows everything electrical.
Thanks as always Ship, that was interesting reading, and I had nothing to do with the initial post.
No, I very specifically do not know everything electrical - I'm still learning myself and do not in any way consider myself expert persay. On the other
hand for what I most do... perhaps I know it often better than others, and perhaps for what I retain in knowledge, what I get a feeling about in being wrong by way of retained knowledge is sufficient often, but nope.. I am not an expert. Lamps.. perhaps I'm working on that anyway but wiring... I do my best and always check or ensure.
Here is what I found so far in further complete re-reading of the Chicago Building code - or at least my 1994-1995 version of it which I once read years and years ago.
14-20-110 (87-300.11.) Conductors of Different Systems
“Conductors of signal or radio systems shall not occupy the same enclosure with conductors of light or
power systems except as permitted for...., for remote-control, low-energy
power and signal circuits in Section 14-60-230 of this title.........”
14-20-120 (87-300.12.) Number of Conductors in
Raceway
“In general the percentage of the total interior cross-sectional area of a
raceway to be occupied by conductors shall not be more than will permit a ready installation or withdrawal of the conductors and dissipation of the heat generated without injury to the
insulation of the conductors. See the following sections of this code:
conduit, Section 14-20-1180; electrical metallic tubing, Section 14-20-1420; surface metal raceways, Section 14-20-1620; underfloor reaceways, Section 14-20-1700; cellular metal floor raceways, Section 14-20-780; wireways, Section 14-20-1950; auxiliary gutters, Section 14-20-2460; theaters, Section 14-32-340; sound recording, Sections 14-32-730 and 14-32-740; and remote control, low-energy
power and signal circuits, Section 14-60-120.”
14-20-1180 (87-346.6.) Number of Conductors in
Raceway (RMT)
“One
conduit shall not contain more conductors of a given size than are specified in Tables 4 to 11 of Sections 14-68-050 to 14-68-100, respectively of this title.
14-20-1420 (87-348.6.) Number of Conductors in
Raceway (
EMT)
“One tubing shall not contain more conductors of a given size than are specified in Tables 4 to 11 of Sections 14.68-050 to 14-68-100, respectively, of this title.
Article XXV-Auxiliary Gutters
14-20-2420 (87-374.2.) Purpose
“Auxiliary Gutters, used to supplement wiring spaces at
meter centers, distribution centers, switchboards, and similar points of interior wiring systems, may enclose conductors or but-bars, but shall not be used to enclose switches, overcurrent devices or other appliances or apparatus.”
14-20-2460 (87-374.5.) Number of conductors in
Raceway
“Auxiliary gutters shall not contain more than 30 conductors at any cross section unless the conductors are for signaling circuits or are control conductors between a motor and its starter and used for starting duty. The sum of cross sectional areas of all contained conductors at any cross section of an auxiliary gutter shall not exceed 20 per cent of the interior cross sectional area of the gutter.”
Something of interest/curious I found not related:
14-20-2780 (87-384.26.) Number of Overcurrent Devices
in One Panelboard
“Not more than 42 overcurrent devices, other than those required for the mains, shall be installed in any one enclosure. For the purposes of this Section a two pole
circuit breaker shall be considered two overcurrent devices; a three pole
breaker shall be considered three overcurrent devices.
Panelboards shall be equipped with physical means to prevent the installation of more overcurrent devices than that number for which the panelboard was designed rated and approved. (See 14-16-1010(f)).”
14-20-2790 (87-384.27.) Overcurrent Protection
“Except where the panelboard is approved as service equipment and is being used as in (a-3) of Section 14-16-640 a panelboard supplied by conductors having overcurrent protection greater than 200 amperes shall be protected on the supply side by overcurrent protective devices having a
rating not greater than that of the panelboard.
Snap switches rated 30 amperes or less and installed in a panelboard shall be protected by overcurrent devices not in excess of 200 amperes.”
14-28-860 (88-520.5.)
Auditorium Wiring Methods
[Very curious in it’s literal concept but The Stage, is covered in the next section so in theory this concept would not include the fly system itself, but there is no specific exemption here that would clarify this. (14-28-870h later about suspended boarders does not cite this safety cable of it for instance however so such a rule probably does not have it’s concept for the stage non-audience accessible area perhaps. Also curious about solder terminals on foot lights in this 14-28-870 chapter.) Still never seen a ceiling chandelier over the house in a proper theater space that had a safety cable on it or at least two point separate derived suspension. Assuming that the wiring to the fixture was not sufficient to provide an alternate means of support it’s curious. It would mean however in a more specific sense, that any FOH lighting support or bars, would need a separate alternate means of support of that bar which could in theory be say individual hoists (more than two) say in supporting a truss or pipe where if one failed, the others could be sufficient. This or a chain support hoist mechanism as not mentioned which would or could be sufficient all around without the alternate safety necessity. As for the overhead chandeliers that get lowered down so as to change lamps... I don’t know how such things given the below gets grand fathered or compliant.]
d. “Ceiling fixtures in
auditorium or other parts of the theater, which, for the purpose of lowering the same, are suspended from steel cable, shall have an additional means of support which shall in itself be sufficient to safely support the
fixture and which shall be entirely independent of the support afforded by the cable.”
14-28-900 (88-520.9.) b.
Portable Incandescent Olivettes and spots
“Where
asbestos covered conductors pass
thru the metal, an approved
bushing shall be employed for each
conductor and the conductors shall be so anchored as to relieve the connections of any mechanical strain.” [This is 1994/1995 Chicago building code and the chapter follows carbon arc followspots and boarder lights. Would have to check the more recent code books but according to this, asbestos cable fixtures are still recognized under code for use. This also that all conductors shall be kept at least ½” from the metal of the enclosure and be solder type. Means that S-4, and most all other fixtures were not acceptable by code at this point by way of that ½" from the body of the fixture - though means of support of the lamp base is not clarified as part of the enclosure or support mechanism, and other concepts of solder type terminals would tend to limit what’s compliant to stuff made last in the 1970's. Hope the code has been updated since the 1930's after the publishing date of my 1994/1995 copy.]
Read 14-28-920... it’s insane and inane by way of what is specified and not concepted for actual use.
Also in my Chicago Code
book, 14-28-940 about “
Portable Conductors” is very telling of where the industry was even 12 years ago, much less useless - like at least 20 years out of step with the industry. Unless a more recent Chicago Code has seriously updated this info which is hopeful, I would say follow the
current guidelines presented by the
NEC for the
stage and consult the Chicago Code to see where problems might be in out of date concepts of compliance. Best judgement after that as well as talking with the inspector of and contractors for your application in gaining their own incites as to how to deal with what’s specified verses what’s appropriate. Most likely what’s in the
NEC will be sufficient and better. The above “Olivettes and Spots” is in reference to a type of
Fresnel and PC spots - not
Leko’s meaning premium early 1960's technology yet they,
footlights and boarder lights are still in 1995 at this
point are still the only
stage lighting fixtures mentioned acceptable for specific compliance in the code. Last reading of this
book like 12 years ago, I didn’t as well understand it’s concepts and easily wrote off many such sections as being out of step. Made me follow the
NEC more in my own work and write off most of the electrical part of this local governing law of what I do
book. I
book marked most of the other than electrical part of the
book in the overall 1349
page building code
book where code compliance was concerned as being important... interesting that the electrical section was not way back when.
14-28-940b at least offers not so distant past code compliance to a past
Controlbooth discussion about wood framed
portable switchboards concepts in such things being ok’ inside a wood box, as long as it has a sheet metal liner. Again, the 1994
book I’m looking at seems 20 or 30 years out of date by way of reality and good practice even for the era it was written. Still while bad practice and archaic, in concept even during this more modern period such things were still acceptable. This as long as such conductors within the panelboard were
asbestos as mentioned in part d, use of the earlier discussed as not so good these days in concept wood framed switchboard that’s tin lined, and wired with
asbestos wire would be acceptable. Also overcurrent protection will be of the
fuse type. No worries... in 1994, “All circuits leaving the switchboard shall have a feuse in each
conductor. Circuits from
portable switchboards directly supplying equipment containing
incandescent lamps of the medium
base or smaller types shell be protected by overcurrent devices having a
rating or setting of not more than 15 amperes. Circuits for heavy-duty lampholders may be used, if overcurrent protection conforms to provisions of article II of Chapter 14-16. Other circuits shall be provided with overcurrent devices with a
rating or setting not higher than the
current required for the connected load.”
Just reached the end of the 1994/1995 guidience and Chicago rules on theater wiring... No mention of an overall compliance with the
NEC that’s further refined by the Chicago Building Code anywhere in the electrical part of the Code. Means Lekos - especially S-4 Lekos are not acceptable by code by way of this
book from what I read. Also means lots of other curious specific to what’s specified concepts or lack there of. For instance, nowhere in the code did I read about a requirement of “extra hard service” cable for use in all conditions or conditions other than direct support by
truss or pipe and not other instances such as the floor or cable
drop as specified by the
NEC for similar over 100 seat places of assembly.
More later as I continue re-reading the Chicago Building code. Fascinating that while I don’t consider 1994 that old, it’s a world and a day different than what I would hope the
current Chicago Building Code electrical section specifies for use.