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CARE AND ATTENDANCE.- A competent man must be kept on duty in the room where generators are operating.
Oily waste must be kepi in metal cans and removed daily.
CONDUCTORS. — From generators, switchboards, rheostats, or other instruments, and thence to outside lines, conductors must be:
1. In plain sight.
2. Wholly on non-combustible insulators, such as glass or porcelain.
3. Separated from contact with floors, partitions or walls through which they may pass by non-combustible insulating tubes.
4. Kept rigidly so far apart that they cannot come in contact.
5. Covered with non-inflammable insulating material sufficient to prevent accidental contact.
6. Ample in carrying capacity to prevent heating. (See Capacity of Wires Table.)
7. Connected by splices or joints equal in carrying capacity to the conductors themselves, soldered, if necessary to make them efficient and permanent.
8. When under floors or in distributing towers, placed in spaces ample for inspection and ventilation, and provided with special insulating covering. SWITCHBOARDS—Must be:
1. So placed as to make it impossible to communicate fire to surrounding combustible material; accessible from all sides when the connections are on the back; or may be placed against a brick or stone wall when the connections are entirely on the face.
2. Kept free from moisture.
3. Made of non-combustible material, or of hard wood, filled to prevent absorption of moisture.
4. Equipped with bars and wires in accordance with Rules 1, 2, 4, 5, 6, and 7, for placing interior conductors. RESISTANCE BOXES AND EQUALIZERS—Must be:
1. Equipped with metal or non-combustiblo frames.
2. Treated as sources of heat.
3. Placed on the switch, or a distance of a foot from comustible material, or separated therefrom by asbestos or cement. LIGHTNING ARRESTERS—Must be:
1. Attached to each side of every overhead circuit connected with the station.
2. In plain sight.
3. On the switchboard, or in an equally accessible place, away from combustible material.
4. Connected with at least two earths by separate wires of large size.
5. So constructed as not to maintain an arc after the discharge has passed.
TESTING. —All series and alternating circuits must be tested every two hours while in oreration to discover any leakage to earth, abucrmal in view of the potential and method of operation.
All multiple arc low potential systems (300 volts or less) must be provided with an indicating or detecting device, readily attachable, to afford easy means of testing where the station operates perpetually.
Data obtained from all tests must be preserved for examination by insurance inspectors.
CLASS B.-ARC (SERIES) SYSTEM.
OVERHEAD CONDUCTORS. — Alloutside overhead
conductors (including services) must be: 1. Covered with some insulating material not easily abraded.
2. Firmly secured to properly insulated and substantially built supports, all the wires having an insulation equal to that of the conductors they confine.
3. So placed that moisture cannot form a cross connection between them, not less than a foot apart and not in contact with any substance other than proper insulating supports.
4. At least seven feet above the bighest point of flat roofs and at least one foot above the ridge of pitched roofs over which they pass or to which they are attached.
5. Protected, whenever necessary, in view of possible accidents to conductors or supports, from possibility of contact with other conducting wires or substances to which current may leak, by dead insulated guard irons or wires. Special precautions of this kind
must be taken where sharp angles occur, or where any wires might possibly come in contact with electric light or power wires.
6. Provided with petticoat insulators of glass or porcelain Porcelain knobs and rubber hooks are prohibited.
1. So spliced or joined as to be both mechanically and electrically secure without solder. They must then be soldered to insure preservation, and covered with an insulation equal to that on the conductors.
The following formula for soldering fluid is approved :
Saturated solution of zinc . . 5 parts. Alcohol . . . . . . 4 parts. Glycerine . . . .
1 part. Conductors should not be run over or attached to buildings other than those in which light or power is being, or is to be, used, but on separate poles or structures always easily inspected.
SERVICE BLOCKS must be covered over their entire surface with at least two coats of waterproof paint, and so maintained.
Telegraph, telephone, and similar wires must not be placed on the same arm with electric or power wires, and should not be placed on the same structure or pole.
ALL INTERIOR CONDUCTORS—Must be:
1. Where they enter buildings from outside terminal insulators to and through the walls
covered with waterproof insulation, and must have drip loops outside, preferably slanting upward toward the inside,and bushed with waterproof and non-combustible insulating tube.
2. Arranged to enter and leave the building through a double contact switch, which will effectually close the main circuit and disconnect the interior wires when it is turned “off.” The switch must be so constructed that it shall be automatic in its action, not stopping between points when started, and prevent an arc between the points under all circumstances; it must indicate on inspection whether the current be “on” or “off,” and be mounted on a non-combustible base in a position where it can be kept free from moisture, and easy of access to police or firemen.
3. Always in plain sight, never covered, except in special cases, where an armored tube may be necessary.
4. Covered in all cases with a waterproof non-combustible material that will adhere to the wire, not fray by friction, and bear a temperature of 150 degrees F. without softening.
5. In dry places, kept rigidly apart at least ten inches, except when covered in addition to insulation)—by a waterproof, non-conducting and non-inflammable tubing, which must be strong enough to protect the insulating covering from injury. Conductors thus placed may be run not less than three inches apart, and be fastened with staples, under which are placed mechanically rigid insulating strips or