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tion,

All single conductors shall be insulated 121..: Insulawith — All duplex conductors shall be insulated with — Duplex conductors and all single conductors larger

B. & S. 1 than - iB. W. G. s stranded.

(See p. 95, sec. 87.)

122. Insulation Resist

ance.

division of

Risers

From the switchboard (or centre of dis- 123. Subrisers

Feeders). tribution) — groups of risers į shall

feeders be carried to the following points: ( Riser )

(riser Group No.1 to - group ? No. ( Feeder )

feeder 2 to , etc.

Every conductor in each

(riser,

groups of risers, (and main shall be ( feeder, provided with an independent tube.

(Riser

Group No. 1 shall feed all lights (lo. | Feeder

(riser )

cation),

group No. 2 shall feed, etc.

feeder

124. Location

From the switchboard

es centre of distribution

of Risers

the

{ Feeders ). I risers

. shall be carried

I shall be carried to — and feeders thence upward in (channels, elevator shaft, etc., with location) to their respective junction boxes.

125. Mains

tion boxes).

125. Mains (If From the } feeder he: I riser

junction boxes, taps terminate in secondary junc mains shall be carried to secondary junction boxes where all tap lines shall centre. riser l

No. 1 shall be carried - mains terminating at — ; from i feeder š No. 2, etc.

From

feeders

| riser

Į No. 2, etc.

(Note.-In certain cases it is advisable 126. Tap& 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 dis

( main tributing circuits shall be run to the various outlets as specified in the schedule and located on the plans. For all taps duplex conductor requiring but one tube may be employed provided the current required does not exceed — amperes.

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The terminals of all the risers !

y feeders ; mains and taps shall be brought together in junction 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 convenient insertion of the cut-outs and switches specified.)].

128, Cut-Outs. (See p. 99, sec. 94.) 129. Fuses. (See p. 99, sec. 95.) 130. Switches. (See p. 99, sec. 96.)

Supports.

131. Fixture Where no gas pipe or other support

for the 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.

132. Sizes of All tubes shall be of sufficient size to

allow the wires to be readily drawn in, withdrawn and reinserted at will.

133. Fasten

ing8.

133. Fasten- Tubes, whether concealed or on the

surface, should be held in place by the fastenings especially designed for use with this conduit.

134. Joints.

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

135. Elbow Limitations.

Where more than three elbows are un- li mitallbow avoidable 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 136. Outlets. terminal boxes leaving the outlets so protected as not to be injured by the plasterers.

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137. Floor Work with Brass or Un

Conduit.

To guard against mechanical injury and 137. the destructive action of cement all floor armored conduits shall be made of double tube, one telescoped 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.

Each side of circuits carrying more than 138. Separa.

tion of Wiros.

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