The Moving picture world (January 1926-February 1926)

75d Moving Picture World February 20, 1926 Bluehook School Answers Nos. 434 to 438 Question No. 434 — What is meant by an "inclosed switch" and where is the use of such a switch imperative in a projection room? There is an excellent bunch of answers to this one. E. Steele, Salt Lake City, Utah ; C. H. Hanover, Burlington, Iowa; Sackville, New Brunswick, on stationery of Imperial Theatre, but no name attached (again I ask you to put your full name and address on the FIRST page of your answers, and your name on each page thereof. Answers to questions and letters accompanying them are separated immediately upon arrival, and if we do not then notice that the name is not on the answer we're sunk, because we do not again see that particular answer for from one to three weeks) ; F. H. Moore, Taunton. Massachusetts; W. C. Budge, Springfield Gardens, Long Island ; G. L. Doe, Chicago, Illinois; Thoreau and Clark, Vancouver, British Columbia; Roy Saxon and John Read, Lufkin, Texas; James Harrison, Arcade Theatre, Georgetown, Ohio; William C. Turk, Mexico, Missouri; L. T. Thomas, San Antonio, Texas ; Joseph Robinson, Denver, Colorado, and Frank C. Hirshman, Montreal, Ontario, made good on this one, and on the rest of the series too. The term "inclosed switch" Is used to desle:nate or describe a knife switch which has a housing: of sheet metal to protect the live parts thereof from accidental contacts. The handle of such switches protrudes through the housing: so that the switch may be opened or closed without disturbing the housing:. Of course, strictly speaking-, any switch havins: its live parts Inclosed, or even a switch in a metal cabinet. Is an "Inclosed" switch, but In practice the name or term is applied only to coverings similar to the one 1 have described. Inclosed switches are imperative for the projector table switch; also for any isolated projection room switch not inclosed in a fire proof cabinet, though there are presumed to be none of the latter. A very excellent reply. Brother Hanover, or so it seems to the editor. Question No. 43S — Name one rule it is well to adhere to in connecting inclosed switches, and tell us why it should be thus. AU the above, plus J. T. Schofield, Jacksonville, Florida, made satisfactory answers to this one. Brother Steele says : Be sure the blades are connected on the load side, and ttie contact jaws to the line side. "Which is short and correct, so far as it goes. The Sackville man says: It is better to so connect Inclosed switches that the blades are 'dead' when the switch is 'open.' The same thing applies to all knife switches, though 11 is not always possible to so connect them. It is especially important that inclosed switches be thus connected, to prevent trouble should the blades come into contact with the housing when the switch Is open. Right, brother. Of course, switch blades are not supposed to come into contact with the housing. Also a man is not supposed to use swear words when he lambasts his finger with a hammer. In fact he is not supposed to smack his finger with a hammer at all, BUT things 'appen, as the Cockney says, particularly if the conditions are such that a "happen" is invited. Correct your inclosed switches as Brothers Sackville and Steele have suggested. Friend Budge adds this idea: When the inclosed projector table switch is In open position the blades should be electrically "dead." Should the connection between blades and cross bar to which handle is attached work loose, the blades mlg-ht come into contact with the switch covering when the switch Is open, and if the blades be "alive" the whole projector would be charged, under which condition It Is not impossible to set fire to the film, it the projector ground be no* perfect. Excellent, PTother Budge. Under condition if in removing a reel from the upper magazine, it should touch both the magazine and a conduit pipe or other well grounded metal at the same time, a fine, large, fat spark would result, and as you have said, the film might be made into a rather smoky, fast burning torch. Go wash your ears, friend Budge, and pass up to the head of the class. Question No. 436 — What rule should govern in locating projection room switches and switchboards ? Everyone, plus Charles Oldham, Norwich, Connecticut, answers correctly. Doe says : Convenience. Which is not an answer quite worthy of our Chicago friend. Let him read the reply of Brothers Thoreau and Clark, who say: The following Underwriters' rules must be strictly observed with relation to switchbof.rds: (1) ^^ust be so placed as to reduce to a minimum the danger of communicating fire to adjacent combustible material. Switchboards must not be built up to the celling. If possll>Ie, there must be a space of three feet between the top of the board and the ceiling. The space back of the board must be kept clear of rubbish and not used for storage purposes. (2) Mutt be made of non-combustible materials. (3) Must be acesslble from all sides when connections are on the back, but may be placed against a brick or stone wall -when the wiring Is entirely on the face. If wiring Is on the back, then there must be a clear space of not less than eighteen inches between the wall and apparatus on the board. Even If the wiring Is on the face It Is much better to have the board set out from the wall. (4) Must be kept free from moisture. (5) Wires with an Inflammable outer braid covering, when brought close together, as at the back of the switchboard, must, when required, each be encased in a tight, noncombustible outer covering. Flame proofing must be stripped back on all cables a sufficient distance to give the in.«',ilation necessary for the voltage of the circuit on which the cable Is used. With the above rules complied with, one might suggest that switches and switchboards In a projection room should be placed where they will be most convenient, every SPECIAL ROLL and MACHINE TICKETS Your own special Ticket, any colors, accurately numbered; every roll guaranteed Coupon Tickets for Priie Drawings: 5,000 (or $7.00. Prompt shipments. Cash with tho order. Get the samples. Send diagram for Reserved Seat Coupon Tickets, sei-iai or dated. ROLL AND MACHINE TICKET PRICES Five Thousand $3.50 Ten Thousand COO Fifteen Thousand 7.00 Twenty-five Tliousand 9.00 Fifty Thousand 12.S0 One Hundred Thousand Ig.OO National Ticket Co, Shamokin, Pa. thing considered, and If possible where a full view of the screen and stage may be hadfrom a position beside or in front of It. This latter w-III. of course, vary widely with the projection room Itself. Of course the Underwriters" rules were not a part of the question, but they fit in very -well ■ nevertheless. I left my copy of Underwriters' rules at the summer home, and have neglected to get another for use here in the city. I therefore, have not checked over what Brothers Thoreau and Clark have said, but so far as my memory goes it is correct. Hanover handles the matter according to what I have no doubt but that Brother Doe had in mind. He says : The location of projection room switches and switchboards will depend entirely upon the peculiarities of the Individual Installation. Without entering Into a discussion of friderwriters' rules regarding switchboards, they must, so far as these rules will permit, be so placed that a maximum of accessibility and convenience is attained. If the projectionist is to handle all auditorium lighting, then the sw itches or dimmer controlling such lig'htlng MUST for good results be so located that he may have a view of the auditorium while manipulating the switches or lighting controlls. If the projectionist does not handle the auditorium lighting, then the location of switches is merely a matter of having them In the most convenient location which local and Underwriters' rules will permit. The question is one which It seems to me cannot possibly be answered In any other way. Correct, Brother. I think yourself and brothers Thoreau and Clark may place yourselves in the spot at the head of the class and scrap it out to see which remains — and may there be ample supply of arnica, courtplaster and raw beefsteak. Question No. 437 — Should emergency light switches be on the main house switchboard, or where should they be and why? Brothers Sa.xon and Read say: Emergency light switches should never be on the main house switchboard. The Bluebook says they should be either in the box office or In the manager's office, though we personally believe it would give greater protection to the audience were they placed in the projection room, particularly It they be not separately fused, but instead are only fused by circuit and at or near the circuit switch. It is not an unusual thing, particularly in the smaller theatres, for the ticket seller and the manager, one or both, to leave before the last show is finished. In many instances the manager may leave as much as an hour before the close of the last show. Under this condition if the emergency switches and fuses be locked up In the manager's office or In the box office — well. If an emergency circuit fuse blows, you are out of luck! On the other hand if the switches and fuses are located In the projection room, tliey are under control of a man or men who must be and is there as long as a show Is on. Not SO bad, but it only answers half the question. With your permission, the editor will himself deal with the matter as he sees it. There is a certain amount of virtue in what Messrs. Saxon and Read have said. Their line of reasoning is good, but the primary reason for locating the emergency switches off the main house board is because in case of an alarm of fire, some excitable person, an usher for instance, might rush to the main board to light the auditorium and pull the emergency light switches. Elxcited men or women often do strange things. Personally, I see no objection, save the length of circuits involved, in locating the emergency light switches in the projection (Continued on page 758)