Зображення сторінки

34. Founda


(See Note: p. 46, sec. 22.)

The foundation(s) for the(se) dynamo(s) shall be built by the contractor

We purchaser of—, laid —, or of other material subject to the approval of the engineer, lands

: and shall be of sufficient length, width, and depth to safely and firmly sustain

toin their l weight. The foundation(s) shall be capped with a framing of well-seasoned timber securely fastened thereto, the dynamo baseframe(s) being securely fastened to the framing or to the foundation through the framing, both framing and baseframe being secured in such a manner as to prevent lateral motion in either direction and to give an even bearing surface at every point. If metal is used to fasten framing or baseframe to the foundation it must be thoroughly insulated where it passes through them, and at all places liable to come in contact with the dynamo must be countersunk and covered with

a moisture-proof insulating compound.

All necessary excavating and filling and the removal of all debris shall be done by the contractor L. done by the purchaser who shall also restore the floor in the following manner: - The height of the dynamo baseframe(s) above the floor line will be

[blocks in formation]

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

There shall be provided with each dynamo one voltmeter or pressure indicator which shall remain constantly in circuit so as to indicate at all times the pressure at the point to which it is connected; one brush jig for trimming the brushes; one insulating baseframe provided with rails and a suitable device for shifting the position of the dynamo to alter the belt tension; if of the constant-potential type, one hand regulator made entirely of incombustible material, a compensator or suitable balancing device for keeping the current in each circuit practically constant; if of the constant-current type a reg. ulator for so controlling the potential as lights are turned on or off that the current shall not vary appreciably from its normal value under any condition of load. There shall be provided for each circuit one ampere meter for indicating the current in said circuit, one ground detector which shall continuously indicate the insulation from the ground maintained at both poles and approximately the distance of any ground from the station, and one pair of lighting arresters. There shall also be provided one testing set capable of measuring up to - ohms.

[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]


This contractor shall carry to the 36. Cables to switchboard location at — all regulator, exciter, auxiliary and main wires, leaving the ends coiled up neatly, properly tagged and sufficiently long to make the necessary switchboard connections. All main wires shall have a capacity of at least - C. M. per ampere and no wire smaller than - B. & S. or — B. W. G. shall be used. All wires shall be in

sulated with — ; shall be run — ; when of opposite polarity shall be separated at least — ; and where crossing each other, wires of other circuits, or passing near metal pipes, girders, etc., shall be further protected by - In no case shall insulated wires be carried in such proximity to heated surfaces, vapors or air as to en. danger their insulation.

[blocks in formation]

39. Summary. (See Note: p. 52, sec. 27.)

Each bidder shall fill out completely
the following summary:
Number of dynamos . . . . .
Trade number or designation
Rating in volts . . . . .
Rating in amperes . . . . .'
Direct or alternating current ..
Constant or varying current ...
Constant or varying potential ..
Series, shunt, compound, self or

separately excited . . . . . Rating of exciter in volts ... Rating of exciter in amperes . .Trade number or designation .. Regulation by hand or automatic Number of fully loaded circuits pos

sible to operate per dynamo . Volts per — c. p. lamp · · · Amperes per — C. p. lamp . . H. P. required to be delivered at

the pulley at full load ...

(See p. 53, sec. 28.)

40. Switch


board Apparatus and Connections.

There shall be placed upon this switch- 41. Switchboard, in addition to all 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. For systems operating dynamos and circuits in parallel, the appliances and connections shall be such as will permit adding to or taking from the circuit any

« НазадПродовжити »