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123. Sul). division of Riser's Feeders

to

From the switchboard (or centre of distri

riser's bution) groups of risers

of risers shall te carfeeders

Riser
ried to the following points: Group No. 1

Feeder
riser
group

No. 2 to etc.
feeder

riser Every conductor in each group of risers

feeder
and main shall be provided with an inde-
pendent tube.

Riser
Group No. 1 shall feed all lights (loca-
Feeder

riser tion), 3 group

No. 2 shall feed, etc. feeder

ion

124. Location

of Risers Feeders )

switchboard From the

the 7 centre of distributions

- and thence 5 upward in (channels, elevator shaft, etc., with location) to their respective junction boxes.

Feeder

S From the

125. Mains (If taps terminate

iu secondary shall be carried to secondary junction boxes junction

boxes). where all tap lines shall centre. From

mains

(riser)

No. 1 shall be carried
feeders
terminating at

S
-;

from

feeder : No. 2, etc.

126. Taps.

(Note.—In certain cases it is advisable to
run the circuits in such a manner that no
room shall be dependent on one circuit only;
if so desired, it should be added under this
heading.)

riser
From the feeder junction boxes distrib-

main
uting circuits shall be run to the various out-
lets as specified in the schedule and located
on the plans. For all taps duplex conductor
requiring but one tube may be employed pro-
vided the current required does not exceed

ampères.

The terminals of all the feeders

, }

127. Junction

Boxes.

mains

and taps shall be brought together in junc-
tion boxes at the points designated in this
specification and on the plans, and connected
with their respective cut-outs and switches;
(unless the wiring contractor does not furnish
cut-outs and switches, in which case add: in
such a way as to permit the easy and conven-
ient insertion of the cut-outs and switches
specified.)].

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(See p. 81, sec. 95.)

129. Fuses.

130. Switches.

(See p. 81, sec. 96.)

Where no gas pipes or other support for the 131. Fixture

Supports. fixture exists, the special form of terminal box designed to furnish such support shall be employed and shall be substantially fixed to a suitable foundation in the ceiling or wall.

Tubes.

All tubes shall be of sufficient size to allow 132. Sizes of the wires to be readily drawn in, withdrawn and reinserted at will. A quarter-inch tube will be permitted only where space is extremely limited.

133. Clips.

Tubes, whether concealed or on the surface, should be held in place by metal clips; the use of staples for such purpose will not be allowed where it can be avoided.

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The tubes shall be cut squarely, reamed out 134. Joints. smoothly, and the ends joined by the use of the coupling designed for that purpose.

135. Ellow Limitations.

Where more than four elbows are unavoidable, an intersection box. shall be inserted to relieve both the wires and the tubes of strain when the wires are being drawn in.

All tubes shall emerge at outlets in termi- 136. Outlets. nal boxes, leaving the outlets so protected as not to be injured by the plasterers.

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137. Floor

Work.

To guard against mechanical injury and the destructive action of cement, all floor conduits shall be made of double tube, one tele. scoped within the other, and both the outer and inner tubes joined in the usual manner. The outer tube shall, in the case of contact with cement, be alkali proof. As a further protection, floor tubes shall be covered during construction with a light board. Such other precautions shall be taken to insure the safety of the tubes as the character of the building and work require.

128. Separation of Wires.

Each side of circuits carrying more than

ampères shall be run in a separate tube. Wires forming parts of two distinct circuits shall in no case be inclosed in the same tube.

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(See p. 82, sec. 98.)

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(See p. 85, sec. 107.)

147. ThreeWire System

Adapted to the Two-Wire

System.

Interior Wiring for Central Station Plants.

of Lights.

c. p.,

This specification contemplates the com- 148, Number plete installation of

incandescent lamps located in blocks as designated on the plans hereto attached and made a part of this specification.

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(Note.-Specify whether bids for two-wire 152. System. direct-current systems only, for three-wire direct-current, for two-wire alternating current, or for any system will be considered.)

The fall of potential between the service 153. Variation

iu Pressure. cut-out and the most distant lamp in any building shall not exceed

per cent.

2

All wires used inside of buildings shall be 154. Insula. insulated with

open cleat

of the Work.

All wiring shall be

molding

work, 155. Character

concealed neat in its mechanical appearance and arrangement.

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