Hawkins Electrical Guide ...: Questions, Answers & Illustrations; a Progressive Course of Study for Engineers, Electricians, Students and Those Desiring to Acquire a Working Knowledge of Electricity and Its Applications; a Practical Treatise, Issue 3

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T. Audel & Company, 1917 - Electrical engineering
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Page 778 - ... SPECIAL WIRING. Special wiring for damp places such as breweries, packing houses, stables, dye houses, paper or pulp mills, or buildings especially liable to moisture or acid or other fumes likely to injure the wires or their insulation, should be done with approved rubbercovered wire, and rigidly supported on porcelain or glass insulators which separate the wires at least one inch from the surface wired over, and which must be kept apart at least two and one-half inches. The wire in such...
Page 773 - Must be separated from contact with walls, floors, timbers or partitions through which they may pass by noncombustible, non-absorptive insulating tubes, such as glass or porcelain.
Page 785 - Conduits and gas pipes must be securely fastened in metal outlet boxes so as to secure good electrical connection. Where boxes used for centers of distribution do not afford good electrical connection, the conduits must be joined around them by suitable bond wires. Where sections of...
Page 807 - All poles that are smaller at the top than the sizes agreed upon, are troubled with dry rot, large knots and bumps, have more than one bend, or have a sweep of over twelve inches, should certainly be classed as cull poles. Specifications for electric light and power work should be, and in many cases are, much more severe than those required by telegraph lines. A cull pole, one of good material, is the best thing for a guy stub, and is frequently used for this purpose. A cedar pole is always preferable...
Page 982 - A booster is a generator inserted in series in a circuit to change its voltage. It may be driven by an electric motor (in which case it is termed a motor-booster) or otherwise.
Page 785 - Junction boxes must always be installed in such a manner as to be accessible. h. All elbows or bends must be so made that the conduit or lining of same will not be injured. The radius of the curve of the inner edge of any elbow not to be less than 3i inches.
Page 785 - All elbows or bends must be so made that the conduit or lining of same will not be injured. The radius of the curve of the inner edge of any elbow not to be less than three and one-half inches. Must have not more than the equivalent of four quarter bends from outlet to outlet, the bends at the outlets not being counted.
Page 773 - Bushings must be long enough to bush the entire length of the hole in one continuous piece, or else the hole must first be bushed by a continuous waterproof tube. This tube may be a conductor, such as iron pipe, but in that case an insulating bushing must be pushed into each end of it, extending far enough to keep the wire absolutely out of contact with the pipe.
Page 807 - Never set poles farther than 125 feet apart; 110 feet is good practice. Pole Holes should be dug large enough so that the butt of the pole can be dropped straight in without any forcing, and when the pole is in position only one shovel should be used to fill in, the earth being thoroughly tamped...
Page 732 - The lower limit is specified for rubber-covered wires to prevent gradual deterioration of the high insulations by the heat of the wires, but not from fear of igniting the insulation. The question of drop is not taken into consideration in the above tables.

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