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All costs of such inspection to be borne by the contractor.

This inspection is a part of the test and the work will not be considered ready for acceptance until the certificate has been delivered to —■. .

All work shall be done in accordance 18- insurance

Rules.

with the rules and regulations of .

(Note.—The same considerations that w. Accept

v ance.

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.

The final acceptance will be given only after the completion of the work contemplated tinder 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.

20payment.of (To conform to individual cases.)

INSTALLATION OF DYNAMOS AND SWITCH-
BOARDS.

Low Potential, Direct Current System, Two-
Wire or Three- Wire.

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

(Note.—The following specification IS 21. Dynamos, for belted dynamos; for direct-connected, or direct-driven dynamos it must be modified in several particulars, but there is such considerable difference in the methods adopted by different manufacturers for adapting their dynamos for direct-connecting that it is difficult to frame a single specification to cover them all, and at best it would be an awkward affair. The principal points to be covered are the method of connection, such as by slipping the armature over the extended

engine shaft or connecting engine and dynamo shafts by a coupling; the outboard bearing; the method of supporting the fields; the brush-holder support; the extended foundation box, and the speed.

It should also be mentioned where and by whom the dynamo is to be connected to the engine; how the freight and handling charges are to be divided; and where and by whom tests of the combination, if any are to be made before erection, are to be conducted.)

direct current, constant potential dynamo(s) (each) having a normal

capacity of amperes at volts.

The (se) dynamo (s) shall be

j shunt wound; | j compound wound;)

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 commutator, to such a degree as to endanger the ins ulation 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 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 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 with the proper connections any number may be operated in parallel of whatever ampere capacity, provided the voltage be the same; that when connected so to operate it shall be possible, with ordinary care

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