Publisher's Synopsis
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1896 edition. Excerpt: ... CHAPTER XXI. EDITION of 1896. (CONCLUSION.) C/ass C, Low Potential Systems.--Under section 18, "Conductors," Rule "d" requiring one foot of space between high and low potential conductors wherever they cross one another, is omitted and this rule added: f. Must be protected from mechanical injury, when necessary on side walls, by a substantial boxing, retaining an air space of one inch around the conductors, closed at the top, and extending not less than five feet from the floor, or by an iron-armored or a metal-sheathed insulating conduit sufficiently strong to withstand the strain it will be subjected to, the inner insulating tubing to extend one-half inch beyond the ends of the metal tube, which must extend not less than five feet from the floor. When crossing exposed floor timbers in cellars or rooms, the conductors must be attached by their insulating supports to the under side of a wooden strip not less than one-half inch in thickness and not less than three inches in width. This rule is the same one that has been added under section "b" "High Potential Systems," except that for low potential circuits armored conduit is allowed in place of boxing. Under section 19, "Special Rules," Rule "i" now reads: i. When from the nature of the case it is impossible to place concealed wire on non-combustible insulating supports of glass or porcelain, the wires may be fished on the loop system, if incased throughout in apfroved continuous flexible tubing or conduit. American Circular Loom Tubing is approved for use under this rule This last clause is an addition. In section 2o, '" Mouldings," Rule "c " now reads as follows: c. Must be made of two pieces, a backing and capping so constructed as to thoroughly incase the wire and provide a...
