Provide a mechanical restraint between the cable connector mating
halves so that the connecting pin-pair does not separate due to
mechanical vibration or cable sag. Design the male connector to
protect the pins from cable pulling and to align the two halves
during mating. The connector shall be rated for 600 V and 90
degree C 194 degrees F conductor temperature, with minimum 18 Gage
copper conductors, neoprene or polychlorosulphonate jackets, and
shielding.
b.
Terminal Blocks: Heavy-duty, sliding-link rated not less than 20
A, 600 V with not less than 13 mm 1/2 inch spacing between
terminals. Provide 10 percent spares. Main power supply circuit
terminal blocks and control bus termination terminal blocks shall
be rated not less than 40 A. Design to allow individual circuit
testing without disconnecting cabinet wiring. Design terminal to
receive ring-tongue cable connectors on the field side. Mount
terminal blocks in rows within the panel cabinets at heights
greater than 305 mm 12 inches, for connections of remote devices.
Group and wire terminal blocks by function. Wire using insulated
switchboard wire rated for 600 VAC, 60 Hz, 90 degree C conditions.
Use American Wire Gage (AWG) Size 14 or larger for 120 VAC
control and indicating circuits, AWG Size 10 or larger for 120 VAC
main power supplies and tap circuits, and AWG Size 20 for devices
not greater than 28 V. Permanently stamp or mark the marking
strip with the terminal designation. Do not use self-adhesive
embossed plastic label tape.
c.
Grounding Buses: Minimum 25 by 6 mm one inch by 1/4 inchgrounding
bus running the full length of the panel cabinet sections.
Provide with Number 4, 250 thousand circular mil (MCM) lugs for
ground cable connection at each end. Connect internal grounds to
the ground bus.
d.
Fuse boxes: Provide single-pole and three-pole fuse boxes with
fuses for each set of relaying and metering potential circuits.
Provide plug-in strips to connect 120 VAC supplies to meters and
recording equipment.
2.8.6
Local Hopper Heater Control Panels
**************************************************************************
NOTE: Specify parallel alarm contacts within the
control panel and connect to a terminal block within
the panel to a remote alarm system.
**************************************************************************
Provide each hopper with a factory wired local hopper heater control panel
containing relays, contactors, circuit breakers, and control transformers.
Use non-spliced interconnecting multistrand copper wire with high
temperature (454 degrees C850 degrees F) insulation, from the hopper heater
and from the hopper throat heater, to the local hopper heater control
panel. Locate local hopper heater control panels near the corresponding
hopper. Provide each hopper heater with individual automatic heater
controls having adjustable setpoints and proportional bands. Heaters shall
not operate when access doors are open. Heater voltage shall be [_____]
VAC. Control voltage shall be 120 VAC. Size wiring, circuits, and
controls for 2690 W/m2 250 W/ft2. Arrange heater wiring and connections to
provide a balanced load on a [_____] V, 3-phase power supply system.
Enclose in a NEMA ICS 6 [Type 12] [Type 4] [floor] [wall] mounted enclosure
SECTION 15863N
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