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95-8452
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In normally smoky atmospheres the detector will not
go into alarm as long as the concentration is less than
the fixed sensitivity of the detector. This results in a
sensitive and positive response with the lowest potential
for unwanted alarms.
The main enclosure of the detector contains the electronic
circuitry, alarm relay, and supervision relay.
FaIlSaFE OpERaTION
To ensure reliable operation, the U5005 is equipped with
self-checking circuitry. A regulation photodiode, which
is matched to the smoke detection circuit, continuously
monitors the output intensity of the IRED and adjusts it as
necessary to compensate for an accumulation of dust or
other contaminants, or any other variation that can occur
with temperature and time. A power supervision relay in
the detector provides a trouble output signal in the event
of an input power failure.
The detector uses extensive filtering against RF and
transient interference. In addition, there is a 2 second
time delay before an alarm is generated.
The printed circuit board inside the detector is coated to
minimize the possibility of problems caused by moisture
accumulation.
DETECTOR OUTpUTS
The detector provides a set of Form A (SPST) NO
contacts for connection to the alarm output circuitry
and a set of SPST NC contacts for supervision of input
power. An auxiliary set of Form C (SPDT) NO/NC alarm
relay contacts is also provided for controlling remote
annunciation devices.
The alarm output latches on in the event of an alarm
and an LED located on the outer surface of the housing
is illuminated to provide a visual indication that an
alarm condition has occurred. The detector is reset by
momentarily interrupting input power.
SPECIFICATIONS
OPERATING VOLTAGE—
20 to 28 Vdc filtered supply, with less than 1.4 vpp at 60
to 120 Hz.
OPERATING CURRENT—
Standby:
10 milliamperes.
Alarm:
35 milliamperes.
TEMPERATURE RANGE—
Operating: –13°F to +140°F (–25°C to +60°C).
Storage:
–67°F to +185°F (–55°C to +85°C).
ALARM AND SUPERVISORy RELAy CONTACT
RATING—
1.0 ampere at 30 Vdc, SPST.
AUXILIARy ALARM RELAy CONTACT RATING—
2.0 amperes at 30 Vdc, Form C, SPDT.
jUNCTION bOX—
Body material:
Copper-free aluminum.
Conduit Fitting: 25 mm (female).
CERTIFICATIONS—
CSA:
Certified for use in Class I, Division 2,
Groups A, B, C and D hazardous
locations.
DIMENSIONS—
See Figure 2.
wEIGhT—
2 pounds (0.91 kilogram)
INSTALLATION
The U5005 is intended for surface mounting. See Figure
2. The mounting screw holes are counterbored for No.
8 flat-head screws. Electrical equipment that is used
in conjunction with the smoke detector is connected to
the detector using a terminal strip located in the junction
box that is furnished with the unit.
DETECTOR lOCaTION
The smoke detector is normally mounted on the ceiling not
less than six inches from a side wall. The exact location
of the detector must be determined by an evaluation
based on engineering judgment supplemented, if
possible, by field tests.
For additional information on detector location and
spacing, contact the National Fire Protection Association,
Batterymarch Park, Quincy, Mass. 02269, and request a
copy of NFPA Number 72, the Standard on Automatic
Fire Detectors.
FM
APPROVED
®
