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Each bidder shall fill out completely, so far as it pertains to his apparatus, the following summary:

Number of direct-current dynamos .

Trade number or designation . .

Number of alternate-current dynamos

Trade number or designation . .

Number of exciter dynamos . .

Trade number or designation . .

Rating of dynamos in Arolts . .

Rating of dynamos in amperes . .

Rating of exciters in volts . .

Rating of exciters in amperes . .

Self or separately excited . .

Shunt or compound ....

Reduction recommended in converters'

Make of lamp recommended for use .

Dynamo capacity in c. p. lamps of

the above make . . .

H. P. required to be delivered at pulley
at full load with no loss in the feed-
ers but including exciter . .

(See p. 48, sec. 28.)

63. switchThere shall be placed upon this switch-i>oar.»Aii>i.»r

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ing 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.

For the two-wire, direct-current system the appliances and connections shall be such as will permit any dynamo to be added to or taken from parallel circuit without in any manner affecting the operation of the remaining dynamos in circuit, or the candle power and steadiness of the lamps.

For the three-wire, direct-current system the appliances and connections shall be such as will permit any dynamo on either side to be added to or taken from parallel circuit without in any manner affecting the operation of the remaining dynamos in circuit on that side, or the candle power and steadiness of the lamps; and a breakdown switch for connecting the two outside wires in case it shall become necessary or desirable to operate on the two-wire system.

For the alternating-current system 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, and such that it will be impossible to connect two dynamos together by any arrangement of switches or combination of circuits. (For switchboard connections see sees. 30 and 31, p. 50.)

(See p. 51, sec. 32.) 64. circuits.

Arc Series System, Direct Current.

This contractor shall furnish, and, unless otherwise specified, install the following apparatus and material:

arc light dynamo(s) (each) having a 65. Dyna:i;»(s).

capacity of , c. p., ampere,

volt arc lamps.

Each dynamo shall be provided with a regulator which shall automatically make the proper adjustments for all changes of load from no load to full load, the adjustments to be made in such a way as not to endanger any part of the dynamo, appliances or lamps, nor to cause any perceptible change in the balance remaining in operation; shall be of the latest and most efficient pattern; mounted on a base provided with an adjustable belttightener, so that the belt may be tightened while in operation; capable of operating

under full load for consecutive hours

without increasing the temperature of any part, especially the armature, fields, and commutator, to such a degree as to endanger the insulation or decrease the efficiency of operation; shall have an insulation resistance of not less than ohms between all parts

insulated from each other; shall be adapted to operate at such speed as will allow the use of high-speed, automatic-cut-off engines belted direct; shall be provided with efficient oiling devices; the armature shall be balanced both electrically and magnetically, so that there will be no tendency to spring the shaft, or to draw the armature toward either bearing so as to cause excessive friction and heating, and no vibration; especial attention shall be given the insulation, protection, and separation of contacts, binding posts, and bared surfaces having extreme differences of potential, in order to minimize the danger of accidental shocks, crosses, or grounds under normal conditions of operation; the dynamo(s) shall be so designed and automatically regulated that the power will be automatically proportioned to the number and candle power of the lamps burning at any time.

66' uoi"smla' (See P. 54' sec. 34,)

67. instru- (See Note: p. 45. sec. 23.)

lueuta.

There shall be provided with each dynamo, in addition to the automatic regulator required above, one ampere meter for indicating the current supplied by the dynamo and graduated to read amperes; one brush jig for trimming the brushes; one insulating baseframe, provided with rails and a suitable device for shifting the position of the dynamo

i

to alter the belt tension; one main switch; one pair of efficient lightning arresters; and for the general installation one testing magneto capable of ringing through ohms.

arc lamps of —— nominal candle power. Each lamp shall be provided with a switch by which it may be cut in or out of circuit; shall be regular in its feeding action; shall be free from hissing, flickering, or flaming when provided with proper carbons; shall contain an efficient device which shall automatically cut out a lamp for any reason defective, without interfering with the operation of the remaining lamps in circuit; and shall be simple, strong, and durable in its mechanical construction.

hanger boards for inside use, each 7o^Hauger

hanger board to contain a switch by which the lamp may be cut entirely out of circuit.

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