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that it will be impossible under the ordinary conditions of operation to ground or cross them on themselves or on the armature circuit; if separately excited the exciting dynamo(s) also shall be subject to the general conditions given above, shall

operate at a potential not exceeding

volts, shall be of ample capacity to excite

the fields of dynamo(s) (each) having

a capacity of —— kilowatts, and shall operate with no appreciable sparking at the brushes.

There shall be provided with each dynamo one ampere meter for indicating the current supplied by the dynamo; one voltmeter or pressure indicator which shall remain constantly in circuit so as to indicate continuously the pressure on the primary mains at the point to which it is connected, and shall be so constructed that the scale is plainly visible at a dis

(See p. 61, sec. 34.)

44. Foundations.

(See Note: p. 48, sec. 23.)

45. Instruments.

tance of at least ;one insulating baseframe provided with rails and a suitable device for shifting the position of the dynamo to alter the belt tension; one ground detector which shall continuously indicate the insulation maintained on both sides throughout the system; one pair of lightning arresters; for the field-exciting circuit one hand regulator made entirely of incombustible material, one voltmeter, one brush jig, one double-pole knife switch mounted on an incombustible base, one double-pole fusible cut-out mounted on an incombustible base; if the fields are separately excited there shall be provided with the exciting dynamo one insulating baseframe as above, one endless belt, and also, if it excites the fields of more than one dynamo, one hand regulator for the field circuit of the exciting dynamo, one hand regulator for each of the field circuits of the excited dynamos, and one double-pole knife switch and double-pole fusible cut-out for each of the above field circuits, including that of the exciting dy

namo unless lights are operated therefrom, in which case a switch and cut-out shall be placed in the main circuit before branching off to the various dynamos.

There shall be provided the following 46. convert

numbers and sizes of converters:

Number. Size.

It.

etc. etc.

Each converter shall reduce the voltage on the primary circuit to volts

on the secondary circuit; shall have its capacity plainly marked upon it; and shall be provided with a separate fusebox which shall be so arranged that when replacing fuses or otherwise working about the converter the primary circuit may be opened.

(See p. 63, sec. 36.) SWSKM1

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so. summary. (See Note: p. 52, sec. 27.)

Each bidder shall fill out completely the following summary:

Number of alternators ....

Trade number or designation . .

Number of exciters

Trade number or designation . .

Rating of alternators in volts . .

Rating of alternators in amperes .

Rating of exciters in volts . . .

Rating of exc iters in amperes . .

Self or separately excited . . .

Reduction recommended in con-
verters

H. P. required to be delivered at

the pulley at full load . . .

"•usssl11" (See p. 53, sec. 28.)

boariAtlpa- There shall be placed upon this switchconnections, board, in addition to the dynamo regulating apparatus, such switches, cut-outs and other appliances as are necessary for the proper and convenient manipulation of the circuits, such appliances to be named by each bidder in his proposal.

The appliances and connections shall be such as will permit the operation of any dynamo on any circuit or number of circuits, and the cutting in or out of any dynamo or circuit with certainty and rapidity without in any manner affecting the operation of other dynamos or circuits. (They shall also be arranged in such manner as to render it possible to connect two dynamos in parallel by an arrangement of switches or combination of circuits.) (For switchboard connections see sees. 30 and 31, pp. 55 and 56.)

(See p. 57, sec. 32.)

53. Circuits.

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