second, continuous shall be used. Print speed shall be 6 lines per second.
Provide five separate high-temperature alarm comparators with dual field
adjustable set points wired for assignment to groups of inputs. Provide one
isolated lock-in type alarm contact for each alarm set point for wiring to
external annunciator, and wired for manual reset from a remote push button.
Monitor output printer shall be numeric strip chart, nonimpact ribbonless,
roll-type with take-up reel. Provide extra supply of paper for printing at
least 10,000 lines. Provide for flush panel mounting with printer,
indicators, and operator's controls accessible from the front. Alarm
set-point modules, input modules, and auxiliary chassis shall be mounted
behind panel or adjacent to operator's controls. Controller sensing
element shall be stainless-steel armored bulb and capillary, 7.62 meter 25
feet in length. Controller shall include the following features:
a.
Reset and rate as specified.
b.
Set point, proportional ban, reset and rate adjustment.
c.
Pressure gages for supply and control pressure.
d.
Indicator for process temperature.
e.
Supply air pressure regulator.
Provide thermowell sized for the bulb in accordance with the thermowell
specification. Temperature switch elements shall be dry contact (mercury
switch contacts not acceptable) single-pole-dual-throw, rated for at least
120 volt AC, 4 amp or 125 volt DC, 0.5-amp. Switch enclosure shall be NEMA
12. Sensing element shall be stainless-steel armored bulb and capillary,
or direct-mounted bulb, as specified. Provide thermowell sized for the
bulb in accordance with the paragraph entitled "Thermowells." Factory
adjust each switch to the proper setting before shipment to the jobsite.
Indicate the factory setting on the device tag.
2.12.5.1
Thermometers
Thermometers shall be dial type with an adjustable angle suitable for the
service. Provide thermowell sized for each thermometer in accordance with
the thermowell specification. Fluid-filled thermometers (mercury is not
acceptable) shall have a nominal scale diameter of 125 mm 5 inches.
Construction shall be stainless-steel case with molded glass cover,
stainless-steel stem and bulb. Stem shall be straight, length as required
to fit well. Bimetal thermometers shall have a scale diameter of 90 mm 3
1/2 inches. Case shall be hermetic. Case and stem shall be constructed of
stainless steel. Bimetal stem shall be straight and of a length as
required to fit the well.
2.12.5.2
Thermocouples
Pipe thermocouples shall be Type J, iron-constantan element, ungrounded,
for pipeline mounting in a thermowell. Provide protective sheath, screw
terminal head, and the thermowell sized for the service specified. Element
shall be at least 20 gage wire, with 2 hole insulators, 304 stainless-steel
sleeve, silver plug tip, spring loaded. Head shall be universal type with
screwed cover and chain and terminal connector. Provide stainless-steel
nipple as required for head to clear insulation by at least 50 mm 2 inches.
Well shall be sized for each thermocouple in accordance with the
thermowell specification. Duct thermocouples shall have Type J ungrounded
element with 20 AWG iron-constantan wires 2 hole insulators and universal
SECTION 15864N
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