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 elec-
tronic circuitry, alarm relay, and supervision relay.
FAILSAFE OPERATION
To ensure reliable operation, the Model 30-3003 is
equipped with self-checking circuitry. A regulation
photodiode, which is matched to the smoke detec-
tion circuit, continuously monitors the output intensity
of the IRED and adjusts it as necessary to compen-
sate for an accumulation of dust or other contami-
nants, or any other variation that can occur with tem-
perature 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 sec-
ond time delay before an alarm is generated.
The printed circuit board inside the detector is coat-
ed 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 con-
trolling remote annunciation devices.
The alarm output latches on in the event of an alarm
and an LED located on the outer surface of the hous-
ing 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.
Cover:
Feraloy.
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 Model 30-3003 is intended for surface mounting.
See Figure 2. The mounting screw holes are counter-
bored for No. 8 flat-head screws. Electrical equip-
ment that is used in conjunction with the smoke
detector is connected to the detector using a termi-
nal strip located in the junction box that is furnished
with the unit.
DETECTOR LOCATION
The smoke detector is normally mounted on the ceil-
ing 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 sup-
plemented, 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.
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