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however, often be advisable to designate them by their current carrying capacity in ampères to provide for the use of low volt as well as high volt lamps. The form of schedule for switches can also be used for meters, but in this case the current consumed by the lamp should be given, and it should be clearly specified whether the meter is to measure direct currents only, alternating currents only, or either direct or alternating currents, also whether two or three wire.
In the lamp schedule the vertical column of outlets gives the total number for each location, the horizontal line across the bottom of the page gives the total number of outlets of each size in the building, the sum in each case should be the same. The vertical column of lights gives the total number of lights in the building, this sum may be checked from the horizontal line of totals by multiplying those totals by the number of lights per outlet given at the top and adding the results. If the results obtained by the two methods do not agree some mistake has been made either in the arithmetical work or in placing outlets under the wrong heading; the results, to be correct, must agree. The division into "side” and “ceiling” outlets is important to the contractor, since the quantity both of labor and material required is often very largely dependent upon this relation, which inay also determine the method of running the circuits.
193. Specification for Steam
Specification for Steam Plant. (Note.—Though technically steam engineering is not within the province of the electrical engineer, yet in practice electrical and steam engineering are so intimately associated, and so many contractors undertake both classes of installation, that I am constrained to add a short specification for a single-expansion, non condensing steam plant of the simplest type. It will be found applicable to many, perhaps the majority, of central station plants up to 100 h. p. or 150 h. p , and for isolated plants where the conditions imposed by municipal and insurance regulations, considerations of the utilization of exhaust steam, or of combining a heating and power plant, and questions of a similar nature do not require special attention.
The form of Warning, Preamble, and General Specification are, with but slight changes, also adapted to this specification.
This contractor shall furnish and erect, complete in all its details, the following steam plant:
horizontal single cylinder, noncondensing. high-speed, gine(s) especially adapted for electric light