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AUTOMATIC SHUNT.

40. Wherever a current of such high electro-motive force is employed that if concentrated on one lamp or motor of the series, it would produce an arc capable of destroying or fusing parts of such lamp, an automatic switch must be introduced in each lamp or motor by which it will be thrown out of circuit before the arc approaches any such dangerous extent.

41.

Means by which those in charge of the dynamo electric machines will be warned of any excessive flow of current, or means whereby the same will be automatically checked, must in all cases be provided.

FUSIBLE OR OTHER AUTOMATIC CUT-OUTS FOR LOW

POTENTIAL CIRCUITS.

42. Wherever a connection is made between a larger and smaller conductor at the entrance to or within a building, some approved automatic device must be introduced into the circuit of the smaller conductor at or close to its junction, by which it shall be interrupted whenever the current passing is in excess of its safe carrying capacity.

43. The safe carrying capacity of a wire is the current which it will convey without becoming painfully warm when grasped for a minute in the closed hand.

CUT-OUT BOXES OR SWITCHES.

44. All cut-out boxes or switches, which shift, transmit, or break a current, must be mounted on incombustible bases, and so arranged as to close one circuit before they open another, and operate in such a manner that no arc can be formed between the contact surfaces when thrown "on" or "off." It must be so far positive in its action that it cannot stop between its extreme positions. It must indicate on inspection whether current is "on" or "off." This rule applies to isolated plants as well as to those connected with central stations.

MOTORS.

45. The Rules and Regulations under the head of capacity of wires, insulation, automatic cut-outs and switches

shall be observed, where electric motors are used, and in addition the motor frames must be properly insulated, and so mounted as to be free from grounds, and each motor shall be provided with an approved switch to prevent an excessive flow of current.

STORAGE BATTERIES.

46. When the current for lights or power is taken from storage batteries, the same general regulations are to be observed.

MEANING OF TECHNICAL TERMS, ETC.

47. High Potential Circuits or Wires. This term includes all wires arranged with the view of carrying currents of more than 250 volts difference of potential between any two parts of the system, even if such current is used to run incandescent lamps.

48. Low potential currents or wires are such as do not carry currents of more than 250 volts.

49. Companies furnishing electricity from central stations must enter into an agreement with the New York Board of Fire Underwriters, binding themselves to test their lines for ground connections at least once every day (and preferably three times per day), and to report the result of such tests to the Board weekly.

50. The rules and regulations of the Board of Electrical Control and all existing regulations of the local authorities in reference to stringing of wires must be strictly observed.

RULES

OF THE

New York Board of Electrical Control

AS TO

OVERHEAD CONDUCTORS IN NEW YORK CITY.

I. No two lines of poles bearing conductors of a like class shall be erected on any street or avenue.

2. No two lines of poles shall be erected on the same side of any street or avenue.

3. Poles shall be set in the sidewalk twelve inches from the outside of the curb, and no pole shall be placed within ten feet of any lamp-post or other pole, except at street corners where necessary in order to support wires running on the cross street.

4. All poles now standing, or to be hereafter erected, shall be branded or stamped with the initials of the company owning them, at a point not less than five nor more than seven feet from the street surface; and when a pole is occupied by wires belonging to more than one company, each group of cross-arms, or where necessary the support of a single wire of different ownership, must be distinguished by some characteristic paint, mark or fastening.

5. Electric light lamp posts shall be in accordance with the plan adopted by the Board.

6. All poles erected for the purpose of carrying lines of more than two electric light or power wires shall be at least forty-five feet high, uniform in size, straight and

painted from top to bottom-a very dark color from the sidewalk to a point eight feet high, and a dark green color above that.

7. All poles for carrying not more than two electric light wires shall be twenty-five feet high, straight, uniform in size, and painted from top to bottom―a very dark color from the sidewalk to a point eight feet high, and a dark green color above that.

8. Cross-arms shall be uniform in length, strengthened by braces, and painted the same color as the poles; the cross-arms of each company being distinguished by some characteristic mark.

9. Each line of poles must be run on one side of the street only, except when absolutely necessary to change to the other side; but this may only be done by the permission of the Board or of its engineer or expert.

IO. Electric light conductors must not be placed upon fixtures erected or maintained for supporting wires of the other class, namely those for signaling, except by permission of the board.

II. Poles shall be uniformly spaced, and about sixty to the mile. This requires on the short city blocks of two hundred and sixty feet, alternately three and two poles to the block.

12. All conductors shall be secured to insulating fastenings, and covered with an insulation which is water-proof on the outside, and not easily worn by abrasion. Whenever the insulation becomes impaired it must be renewed immediately.

13. No wire shall be stretched within four inches of any pole, building or other object without being attached to it and insulated therefrom.

14. Every wire must be distinguished by a number plainly marked on each cross-arm under the insulator.

15. No unused loops from electric light circuits shall be allowed to remain after lamps are taken away, except in cases where it is positively known that the lamp will be required again within three months, and where there is no underground conduit for that class of circuits.

16. All arc lamps must be so placed as to leave a space underneath of nine (9) feet clear between lamp and sidewalk.

17. All wires must be stretched tightly and fastened to glass or porcelain insulators, approved by the expert, with a strap of the same kind of wire.

18. All connections with lines of electric light conductors shall be made at right angles to the same; and connections to buildings shall be run straight across to the building and then down the front of the building.

19. All joints must be as well insulated as the conductors, and the insulation of joints shall be maintained.

20. Every line entering a building shall be controlled by a cut-off, placed near the entrance, in sight, and easily accessible.

21. No wires shall hang within twenty-five feet of the pavement at the lowest point of sag between supports.

22. In the construction of lines the insulation to be used must be approved by the expert of the board in writing, and the insulation resistance must be maintained in accordance with a standard to be not less megohm per mile per hundred volts. And under no circumstances shall underwriters' wire be used.

23. All circuits must be tested every hour, and when a ground comes on, effort must be made to remove it at once. Failing in this, the current must be discontinued, until the insulation is restored.

24. The insulation must be preserved throughout the entire circuit, and if any portion of a lamp or fixture is a part of the circuit and can be touched, it must be insulated.

25. All conductors shall have a resistance uniformly distributed of not more than 30 ohms per mile per ampere, and proportionately less for heavier currents.

26. All existing regulations of the local authorities in regard to the placing of poles and stringing of wires are to continue in force, except when in conflict with these rules; and the rules and regulations of the New York Board of Fire Underwriters must be strictly observed.

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