2.4.2
Element
Heating element shall conform to the requirements of ASTM B 344 for an 80
percent nickel and 20 percent chromium alloy.
2.4.3
Sheath
Sheath shall be of a corrosion-resisting, nonoxidizing metal and shall have
a wall thickness not less than 0.625 mm 0.025 inch.
2.4.4
Insulation
Insulation shall be a granular mineral refractory material, highly
resistant to heat, and shall have a minimum specific resistance of 1,000
megohms per inch cubed at 585 degrees C 1,000 degrees F. Insulation for
the heating cable (winding wrap-around type heaters) shall be suitable for
a conductor temperature of 180 degrees C 356 degrees F.
2.4.5
Terminals
Terminals of the heater, including the leads, shall be watertight and shall
be provided with leads suitable for making connections to a separate
drip-proof terminal box located on the motor frame. The terminal box shall
be readily accessible through the crating, so that winding heaters can be
energized while motors are in storage.
2.5
MAIN LEADS AND TERMINAL BOX
2.5.1
Stator Terminals
Insulated terminal leads shall receive a treatment equal to that of the
motor winding. Six leads shall be brought out of the stator frame and
connections shall be made as required for the current transformers in
paragraph ACCESSORY WIRING AND BOXES. Terminal lugs for connection to the
motor shielded single-conductor supply wiring shall be provided.
2.5.2
Stator Terminal Box
Drip-proof cast iron or steel terminal boxes, treated in the same manner
specified for frames to resist corrosion, shall be supplied for housing the
stator lead connections, surge capacitors, surge arresters, and current
transformers and shall have adequate space to facilitate the installation
and maintenance of cables and equipment. Boxes shall have a [bolted]
[hinged lockable] cover providing unrestricted access, be mounted on the
motor frame, and shall have an auxiliary floor supporting structure, when
required, supplied by the motor manufacturer. Conduit entrance shall be
from the bottom. The boxes shall be designed to permit removal of the
motor supply leads when the motor is removed. A "HIGH VOLTAGE - [ ]
VOLTS" warning sign shall be provided on the cover of the box. When
looking down on the motor/pump assembly, the terminal box shall be located
between [_____] degrees and [_____] degrees [counter-] clockwise from the
discharge elbow of the pump. A ground bus and means for external
connection to the station grounding system shall be provided in the stator
terminal box.
2.6
SURGE PROTECTION
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NOTE: To obtain the most reliable protection for
SECTION 16222A
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