and with adequate removable access panels or doors for maintenance and
removal of any unit without interfering with other units. Proper latching
equipment and hardware shall be provided. Each recorder, indicator, and
control unit shall be identified with nameplates securely fastened to the
panel. Nameplates shall be black over white laminated plastic with the
lettering penetrating the black surface to expose the white. Nameplates
shall be mounted not more than 25 mm 1 inch below the instrument or gauge,
on the centerline. The panel shall have continuous, rapid-start,
fluorescent light fixtures mounted with reflectors providing suitable
shielding to illuminate controls, instruments, gauges, and meters. Field
piping connections shall terminate in one bulkhead-mounted manifold,
located to conform with the installation requirements of the system. Field
electrical wiring shall terminate in a color-coded terminal strip so
located as to conform with the installation requirements of the system.
Electrical tubing or piping connections to controls, instruments, or other
devices on the panel shall be inside the panel and not visible from the
panel front. A suitable plug-in strip shall be provided in the rear of the
panel for any required plug-in electrical connections of the instruments.
Necessary transformers, separate relays, switches, and fuses shall be
installed in a fully enclosed junction box. A fused safety switch shall
serve the 120-volt power supply required for control circuits. If a
pneumatic control system is provided, the panel shall include duplex air
supply filter and regulator set mounted on the rear of the panel with
properly identified pneumatic terminal blocks and low point drain. No
high-pressure lines will be allowed to enter the panel. [If packaged
boiler burner units with integral controls are furnished, the control
equipment may be mounted on a separate free-standing panel for each boiler.
Controllers and indicators specified or required shall be panel-mounted
and tested at the factory complete with relays, transformers, switches,
wiring, valves, piping, and other appurtenances. Wiring and piping within
the panel shall be color-coded or otherwise identified.]
2.8.2
Indicators
Indicator shall be flush mounted with a vertical scale of 100 to 150 mm 4
to 6 inch length. Indicators may be either electronic or pneumatic with
zero adjustment, receiving standard signals form locally mounted
transmitters. Scales shall be in engineering units with an accuracy of
plus or minus 1 percent.
2.8.3
Recorders
Recorders shall be servo mechanism type, or multiple pen type. [Circular]
[Strip] chart type shall be provided. Minimum chart width is 100 mm 4
inches. Accuracy shall be plus or minus 1/2 percent. Each pen shall have
a separate scale calibrated in engineering units. Chart drive shall be 120
volts ac. One year's supply of chart paper shall be provided.
2.8.4
Panel Display
**************************************************************************
NOTE: Steam flow meters will be specified for
boilers having a continuous steam capacity of 4,540
kg (10,000 pounds) or more per hour and shall be
integrating type where indicated. Feedwater meter
will be provided on individual boilers not having
steam flow meter.
**************************************************************************
SECTION 15559A
Page 52
Previous Page
