Зображення сторінки
PDF
ePub

mined for the most part by a consideration of each individual case. The purpose for which the plant is installed, unusual conditions to which any part may be subjected, necessary delays occurring during the process of construction, relation of one part of the installation to another, time intervening between the completion of the plant and its active operation, operation before completion and like considerations should be given careful attention).

All work shall be regularly and systematically tested while in process of construction and any defects found shall be immediately remedied.

The final tests shall be made in the presence of the engineer ,

ne architect { or his representative and the right is reserved by the purchaser) in case any doubt arises as to the fulfillment of the true spirit and intent of the specifications, to demand a test by expert engineers selected as is usual in matters of arbitration, whose decision shall be final on all disputed points, the expense of such test to be borne equally by both parties unless the apparatus or material shall prove defective, in which case the contractor shall bear the expense, and shall also remedy the defects. He shall also be liable for any damage or loss to (the purchaser) resulting from conditions incident to the remedying of such defects,

17. Inspection. During its progress the work shall be subject to the inspection of the engineer? or

. architects or his representative, and of the

- Board of Fire Underwriters. I

- Board of Inspectors. On its completion a | Board of Fire Underwriters / 7 Board of Inspecturs shall be furnished (the purchaser) by the contractor stating that all the insurance rules and regulations under which the work was done have been complied with. All costs of such inspection to be borne by the contractor.

[ocr errors]

certificate

[blocks in formation]

All work shall be done in accordance with the rules and regulations of —

19. Accept

ance.

(Note.—The same considerations that determine the character of the tests will also enter largely into the conditions of the acceptance.)

(The purchaser) will assume no liability nor responsibility for any part of the installation until formally accepted in writing

No part of the installation will be accepted until (the purchaser) is satisfied that it fully complies with the spirit and intent of the specifications.

The acceptance of any portion of the work shall not be construed as a final acceptance, and the failure of any part to perform its proper function shall be sufficient ground for the rejection of the whole,

The final acceptance shall be given only after the completion of the work contemplated under the specifications according to their true spirit and intent, and after the final tests as specified. Such acceptance, however, shall not prejudice any claim which the purchaser) may have for the replacement of defective material for the time specified.

The date of the completion of the final tests shall be taken as the date of such final acceptance, provided such tests prove satisfactory.

(To conform to individual cases.)

20. Terms of Payment.

INSTALLATION OF DYNAMOS AND SWITCHBOARDS.

Low Potential, Direct Current System, Two

Wire or Three-Wire.

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

21. Dynamos. - direct current, constant potential dy

namo(s) (each) having a normal capacity of -- ampères at —— volts.

The(se) dynamo(s) shall be ( shunt wound, compound wound or pro- ) 3 vided with an efficient automatic regu(lator; 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 par, especially the armature, fields, and commutator, to such a degree as to endanger the insulation or decrease the efficiency of operation; shall not spark appreciably with proper care of the commutator and adjustment of brushes, nor under considerable variation of load; shall have an insulation resistançe of not less than -- ohms between all

parts insulated from each other; shail 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 efficientlling devices; the armature shall be balanced both electrically and mechanically 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; the dynamo(s) shall be so designed that the power required will be automatically proportioned to the number and candle power of the lamps burning at any time; that with the proper connections any qumber may be operated in parallel of whatever ampère capacity, provided the voltage be the same; that when connected so to operate it shall be possible, with ordinary care and precaution, to add to or take away from the circuit any dynamo without in any manner affecting the operation of the remainder, or causing any change in the candle power or steadiness of the lamps; and that when two or more are operating on the same circuit in parallel the load may be divided between them in proportion to their respective capacities under all conditions, from no load to full load; and that with the proper connections any number of pairs, a pair consisting of two similar dynamos, may be manipulated in the same manner and with the same effect as single dynamos, as indicated above,

« НазадПродовжити »