Зображення сторінки

• 59. Starting (See D. 46, Sec. 25.) Plant ..". Struction. o e -(See p. 47, sec. 26.) * Royal (See Note: p. 47, Sec. 27.) 61. Summary.

Each bidder shall fill out completely, so far

as it pertains to his apparatus, the following
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 volts
Rating of dynamos in ampères
Rating of exciters in volts
Rating of exciters in ampères
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 e e e
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.) *or - - 63. SwitchThere shall be placed upon this switch-hord Ajar.

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board, in addition to all the dynamo regulat-"notions.

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 secs. 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:

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volt arc lamps. "
Each dynamo shall be provided with a regu-
lator 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 belt-
tightener, 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 com-
mutator, to such a degree as to endanger the
insulation or decrease the efficiency of opera-
tion; shall have an insulation resistance of

arc light dynamo (s) (each) having a 65. Dynanos). not less than — ohms between all parts insulated from each other; shall be adapted -s to operate at such speed as will allow the use * * of high-speed, automatic-cut-off engines belt* -- \ ed 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.

*iola (See p. 54, sec. 34.) "...o. (See Note: p. 45, sec. 23.) to a There shall be provided with each dynamo, in addition to the automatic regulator required above, one ampère meter for indicating the current supplied by the dynamo and graduated to read ampères; one brush jig for trimming the brushes; one insulating baseframe, provided with rails and a suitable device for shifting the position of the dynamo

t * . . .


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to alter the belt tension; one main switch;

one pair of efficient lightning arresters; and

for the general installation one testing mag—neto eapable of ringing through — ohms.

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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 pro- to “o
vided 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 remain-
ing lamps in circuit; and shall be simple,
strong, and durable in its mechanical con-

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There shall be provided

hanger boards for inside use, each "...or hanger board to contain a switch by which “ the lamp may be cut entirely out of circuit.

waterproof hoods, complete with 71. Hoods.
hanger boards for outside use
out-rigger attachments
cross-suspension attachments.

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