paragraph entitled "Temperature Monitor." The acceleration times for each
motor at voltages within the starting voltage specified, when connected to
the driven equipment, shall not exceed the allowable locked-rotor times at
those voltages. In addition to the starting capabilities specified in ANSI
C50.41, following one start with the motor initially at a temperature equal
to the rated-load operating temperature, each motor shall be capable of
making additional starts with a cooling period at standstill between starts
not greater than 45 minutes. Enclosures shall be fabricated of cast iron or
steel, and shall be furnished with corrosion-resistant hardware.
Enclosures shall be weather-protected NEMA Type II. Horizontal motors
shall be furnished with sleeve type bearings. Bearings, bearing brackets,
and end shields shall be split type when available for the frame size and
enclosure furnished. For motors, furnish oil rings; oil reservoirs; sight
glasses located to be readily observable, and marked with the proper oil
level when running and at standstill; and drain and fill piping to a
location where each bearing and reservoir can be flushed, drained, and
refilled. At least one bearing shall be insulated when required to prevent
bearing or shaft damage due to stray shaft currents. Each horizontal motor
shall be mounted on a common baseplate with the driven equipment, or shall
be furnished with separate sole plates and subsole plates to permit removal
of the motor without disturbing the alignment of the driven equipment.
Thermostatically controlled heaters shall be furnished in each bearing oil
reservoir of outdoor motors. Heaters rated 1,200 watts and less shall be
rated 120 volts, single phase; heaters rated above 1,200 watts shall be
rated 240 volts, single phase. One thermocouple type temperature detector
shall be furnished for each sliding type bearing as specified in paragraph
entitled "Slide Bearings." A vibration transducer mounting pad shall be
furnished on the output shaft bearing housing of each motor connected to
equipment specified with a bearing vibration system. Space heaters shall
be furnished on each motor. Space heaters rated 1,200 watts and less shall
be rated 120 volts, single phase; space heaters rated above 1,200 watts
shall be rated 240 volts, single phase. Each motor power lead terminal box
shall be Type II as defined in ANSI C50.41. Each box shall be sized to
enclose connections to synthetic-insulated shielded power cables including
preformed stress cones. Removable molded insulating boots shall be
furnished for factory and field connections in each box. Accessory leads
including temperature detector leads, space heater leads, and current
transformer secondary leads shall be wired to the accessory terminal box.
The motor "A" weighted sound level shall not exceed 84 dBA when measured to
conform to IEEE Std 85 at a reference distance of one meter.
2.10.3.4
Motor Control Centers
Contractor shall furnish motor control centers with starters and controls
for 3 phase motors rated less than 150 kW 200 hp. Separate motor control
centers shall be provided for each of the spray dry absorber-fabric filter
baghouse units and the lime slurry preparation system. The lime system
motor control center shall be located within the system enclosure. Motor
control centers shall be totally enclosed dead-front type suitable for use
on 480-volt, 3-phase, 4-wire, 60-hertz system. Motor control centers shall
conform to NEMA ICS 6 and UL 845. Motor control centers shall consist of
individual vertical self-supporting sections, nominally 508 mm wide, 508 mm
deep, 2286 mm high 20 inches wide, 20 inches deep, and 90 inches high,
bolted together on floor sills. Sections shall be divided into
compartments for control equipment and arranged for future additions at the
ends. Structures shall be rigid and sufficiently braced to prevent
movement of control centers when inserting or withdrawing removable units.
Compartment doors shall be hinged full length and equipped with quick
captive screws and neoprene gasket on each compartment door. Guide rails
SECTION 15864N
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