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of Circuits.

The lights shall be supplied by circuits 166. Division divided as follows:

etc.

Control.

All circuits shall be controlled by 167 Point of switches placed (location.)

The pole line shall be composed of 168. Poles. straight, select, shaved

poles, sound

and free from shakes, checks or large

knots; poles subject to extra strain shall be specially selected and of ample strength to bear the strain.

All poles must be set

of their 169. Setting and Guying.

length in the ground and solidly tamped, must measure not less than

in

diameter at the top, and the distance from the ground line to the lowest cross-arm shall be not less than Corner, ter

minal and other poles subject to extra strain shall be securely guyed wherever possible; where impossible to guy them they shall be set with such rake and to such extra depth that the strain shall not pull them beyond the vertical position,

170. Distances,

171. Painting.

172. Gains and Cross-Arms.

allowance being made for the action of water and frost.

No two consecutive poles shall be set at a greater distance apart than

cept by special permission from

ex

and all poles carrying heavy feeders or mains shall be set not more than apart.

(As desired.)

Gains shall be carefully cut so that the cross-arms make a snug fit and stand at right angles to the pole.

Cross-arms shall be of, thoroughly seasoned, sound and free from large knots; painted -; the vertical distance between cross-arms shall not be less than

Double cross-arms must be placed on terminal poles and corner poles carryB. & S. ing wires larger than

G. }

At all corners making an angle greater

than

two sets of cross-arms shall be

used placed at the proper angle to each other.

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closely in the cross-arms and be nailed in place.

Insulators shall be of glass, pattern, and of a size suitable for the wire they are to hold.

Insulators.

All poles on which cut-outs are placed 174. Steps. shall be stepped.

(Note.--Specify character of soil, as 175. Soil. loam, sand, etc.; also whether rock, marsh land, quicksands, etc., requiring special work.)

All feeder, main and pressure wires 176. Wiring. of bare copper wire; all servinsulated with—;

shall be

ice wires shall be insulated with

All wires shall be so handled as to avoid kinking; wagons, drays, etc., shall not be allowed to drive over them; they

177, Joints.

shall not be dragged along the ground, over cross-arms or through trees in such a way as to injure the insulation; and shall not be allowed to sag unduly between supports, allowance being made for expansion and contraction with changes of temperature. All necessary and proper precautions shall be taken in passing over, through or near buildings of every description, through trees, crossing other lines, turning corners, etc.

Pressure wires shall be carried from the (switchboard) to each centre of distribution unless such centres are connected by an equalizing main, in which case the pressure wires shall be carried to a point on the equalizing main electrically equidistant from the centres of distribution which it connects.

Joints shall be mechanically strong and secure so that no movement of the two ends relatively to each other is possible, and shall be carefully sweat-soldered, the joint being wiped free from any excess of

flux; the solder shall be relied on only to give good electrical connection.

Arresters.

An efficient lightning arrester shall be 178. Lightning placed on the pole, connected to the line

and to a permanent ground for every

of conductor.

Fall of

Potential.

The mains shall be so proportioned 179. Maximum that the maximum fall of potential between the centre of distribution and any service cut-out, including the loss in any transforming device, shall not exceed per cent. under full load.

Alternating Current System.

nating System.

(Note. The specification for the low- 180. Alterpotential system, p. 120, et seq., may be followed in general. There should be added a specification for placing converters on poles where so required, and for running secondary mains where a single converter supplies a number of buildings, including the distance that the secondary main must be kept from the primary.)

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