solid core on perimeter of all symbols, nameplates, etc.
e.
Mounting: Attach to front face sheet by means of contact cement
that may be loosened by a solvent that will not damage face sheet
or symbols. Use of double-faced adhesive tape is not acceptable.
2.12.4.5
Wiring
Interconnecting wiring between the system cabinets and panelboard-mounted
operating stations or subpanels and between separate sections of the system
cabinets shall be prefabricated cables with plug-in connectors at both
ends. Cable connectors shall incorporate a mechanical restraint between
the mating halves to assure that each connecting pin-pair maintains
electrical contact and that the connector does not separate due to
mechanical vibration or cable sag. The male connector shall be of a design
which protects the pins from damage during cable pulling and aligns the two
halves accurately during mating. The connector shall be approved by the
Contracting Officer. Prefabricated cables shall be rated 600 volt, 90
degree C conductor temperature, 18-gage minimum size copper conductors,
overall neoprene or polychlorosulphonate jacket, and shielding if required.
Prefabricated cable length between the panelboard and system cabinets shall
be [_____] meters feet. Provide field terminal blocks in the Flue Gas
Cleaning System panelboard or system cabinets as appropriate for analog and
digital connections of remote devices. Transmitters furnished by this
contract will be wired to terminals in the system cabinets and powered by
the Contractor's power supplies. Field terminal blocks shall be grouped
and wired into the system according to the function or site of the input or
output signals to simplify termination of multiconductor field cables.
Wiring shall be insulated switchboard wire rated for 600 volt ac, 60 hertz,
90 degree C conditions. Size shall be No. 14 AWG or larger for 120-volt ac
control and indicating circuits, No. 20 AWG for low voltage (28 volts or
less) devices, and No. 10 AWG or larger for 120-volt ac main power supplies
and tap circuits. Use heavy-duty terminal blocks rated at least 20
amperes, 600 volts with not less than 15 mm 1/2 inch spacing between
terminals. Terminal blocks for main power supply circuits and control bus
termination shall be rated at least 40 amperes. Terminals shall be
sliding-link type to allow individual circuit isolation for testing without
disconnecting field or cabinet wiring. Terminal shall be designed to
receive ring-tongue cable connectors on the field side. Terminal blocks
for current transformer circuits shall be 2 or 4 point, as required,
short-circuiting type with one shorting screw for each terminal. Identify
each terminal on all blocks by stamping or permanently marking the terminal
designation on the marking strip. Self-adhesive embossed plastic label
tape is not acceptable. Mount terminal blocks vertically in rows on
interpanels within the panelboard and system cabinets with provisions for
cleating external cables entering from the bottom. Location of the
terminal blocks shall be subject to approval by the Contracting Officer.
No terminal blocks shall be mounted at a height less than 300 mm 12 inches.
Provide a quantity of terminals sufficient for both signal and power
circuits required to implement the system plus 10 percent spare for future
modifications. Provide grouping of the following terminals: (1) Analog,
(2) Annunciator, (3) Control. Provide a ground bus running the full length
of the panelboard and system cabinet sections with No. 4-250 MCM lugs for
ground cable connection at each end. The internal copper ground bus shall
be at least 25 by 6 mm 1 by 1/4 inch. Connect internal grounds required to
the ground bus. Furnish one two-tube, 40-watt, 120-volt fluorescent light
fixture with a protective metal grill for the panelboard. Furnish 120-VAC,
duplex, 3-wire polarized-grounding type, specification grade, convenience
outlets in the panelboard. Furnish single-pole and three-pole fuse blocks
SECTION 15864N
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