2.11.20.1
General
Provide a centrally controlled operation, with auxiliary local operation,
and a monitoring control system with graphic display for the ash conveying
system. Provide local control stop-start pushbuttons and indication
stations for [clinker crusher and ash hopper vertical lift door at each
bottom ash hopper] [mechanical exhausters] and rotary ash conditioner. Ash
handling system manufacturer shall provide measuring devices, status
switches, solenoid vales, and auxiliary parts necessary to safely control
and operate the system. Provide related electrical work required to
operate the ash handling system. [Provide detailed control logic diagrams
from ash handling system manufacturer to the manufacturer of the digital
process control and data acquisition system.]
2.11.20.2
Control Panel
Provide a [separate control panel] [subpanel mounted in the main plant
control panel] of NEMA 12 construction, centrally located in the main plant
control room. Panel front shall include a system graphic display as
indicated. Display shall be approximately to scale and painted with an
industrial acrylic enamel. Outline items with 3 mm 1/8 inch wide black
lines. Lettering shall be on engraved plastic screwed to front of panel,
with white letters on a black background. Provide controls for operation
on [_____] volt, [_____] phase, 60 Hz ac. Panel shall be complete with an
annunciator and interlocks, relays, switches, running and safety lights,
and auxiliary parts necessary to safely control and operate the system.
Items located in the door shall be dusttight and oil tight with
push-to-test transformer type indicating lights. Control relays shall be
10 amp, 600 volt class with convertible contacts. Provide and mark
terminals for connections with the exception of the neutral. Panel shall
contain [_____] percent spare terminals. Wiring shall be No. 14 AWG type
THHN stranded. Neutral wire shall be white and remaining wiring of 120
volts or less shall be color coded and labeled. Provide a plastic wire
duct of sufficient size to provide [_____] percent cross sectional spare.
Wiring shall be in accordance with requirements of NFPA 70.
a.
Provide capability to perform the following functions from the ash
handling system control panel [operator interface console].
(1)
System Start
(2)
System Stop
(3)
Auto/Manual/Index Mode of Operation Selection
(4) Selection of Bypass of any Boiler [Bottom Ash,] [Siftings,]
[Economizer] Hoppers
(5)
Manual Index to any Intake
(6)
Selection of Ash Silo for Baghouse Ash
b.
Provide sensors or contact closures for status indication on the
ash handling system control panel annunciator [operator interface
console].
(1)
Conveyor On
(2)
Unit on (one required for each unit)
SECTION 15501N
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