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78. Switchboard Conn plete.

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sets of carbons, a set consisting of one upper and one lower carbon.

(See p. 46, sec. 25.)
(See p. 47, sec. 26.)

(See Note: p. 47, sec. 27.)

Each bidder shall fill out completely the
following summary:
Number of dynamos -
Trade number or designation
Rating in volts . -
Rating in ampères - -
Capacity in — c. p. lamps
Series or shunt wound . . -
H. P. required to be delivered at pulley

at full load with no loss in the line

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This contractor shall furnish and erect the following apparatus and material:

One combination (material) switchboard with a capacity for – circuits, and provided with the necessary sockets, plugs, main and transfer cables, testing connections, and a suitable and convenient device for holding cables not in use. It shall be so arranged and marked that any circuit or series of circuits may be quickly connected with or disconnected from any dynamo with the least possible danger of short-circuits or error. , Sockets shall be so designed that it is practically impossible to short-circuit, ground, or receive a shock from them. All connections with the dynamo leads shall be easily accessible. All wires used in making connections shall have — insulation. All plugs shall have well insulated wooden handles, and the cables shall be covered with soft-rubber tubing or equivalent as an extra precaution. All cables shall be of stranded wire. All joints shall be soldered. All connections to switches, cut-outs, etc., shall be soldered or made with an approved form of lug or setscrew, in all cases care being taken to secure good and sufficient contact to prevent heating and insure permanency; when made with lugs or set-screws they shall be in plain sight and easily accessible for tightening. Connecting wires shall be so run and secured that crosses or grounds are impossible in the normal operation of the plant.

FIXTURES, ETC.

(Note.—No set specification can be made for fixtures and shades; their character must be

79. I’ixtures and Shades.

80. Lamps.

81. Sockets and Receptacles.

82. Meters.

determined wholly from individual requirements. See schedule, p. 107.)

This contractor shall furnish and deliver at —— the following number, sizes, and kinds of incandescent lamps:

* Voltage. Plain. Number. C. P. J. Ampèrage. | Frosted. etc. etc. - – { Colored, etc.

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etc.

stating, also, their make and the make of the socket for which they are adapted.

Lamps shall be guaranteed to have an average life of not less than — hours if burned at their normal voltage. They shall burn with a white light, and shall not blacken under proper use. All lamps giving out or proving defective during the trial period of — days under normal and proper use shall be replaced without charge.

This contractor shall furnish and deliver at —— the following numbers and kinds of sockets and receptacles: Number. Kind. Finish.

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Number. Capacity in Two or three-
ampères. wire.
etc. etc. etc.

INTERIOR WIRING.

Alternating or Direct Current, Two - Wire
System.

The building shall be wired to — lamp out

lets, – switch outlets, (and — rheter outlets) for the equivalent of —, -—c. p., -—

volt lamps. The wiring .shall be (to outlets only) (except for cut-outs and switches; cutouts and switches shall be furnished and installed complete). At each outlet the loose wire shall be neatly coiled and the ends carefully taped.

All wiring shall be for the parallel, two-wire system of distribution.

The fall of potential between the switchboard (centre of distribution) and the (farthest lamp) shall not exceed at — load — per cent. of the initial pressure; this difference to

be divided as follows: } Ho ! — per

cent., mains — per cent., taps — per cent.

All wire used throughout the installation shall be insulated with —.

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Each } Ho, | main, and tap shall test

out with an insulation resistance of at least — ohms. The entire installation shall test out with an insulation resistance of at least — ohms divided by the sum of the number | risers,

| feeders | mains, and taps.
2

of separate

From the switchboard (or centre of distri

risers, • bution) groups of risers, shall be carfeeders, Riser ried to the following points: - Group - No. 1 - Feeder

riser to —, group - No. 2 to —, etc. feeder Riser | Group | No. 1 shall feed all lights (location), Feeder

riser
group - No. 2 shall feed, etc.
feeder

From the switchboard (or centre of dis

tribution) the ło! shall be carried

under cleats,
on insulators, to ——, and thence up-
in molding, etc.,

ward in (channels, wooden conduits, elevator shaft, air shaft, etc., with location) to their respective cut-out boxes,

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