Manual

D-1111-0 1
DISC
Ceiling Mount PIR Detector
Installation Instructions
1. INTRODUCTION
The DISC is the smallest 360° ceiling mounted passive infrared
detector presently marketed.
The DISC provides a nearly conical pattern of maximum 10.5 m
(36 ft) diameter, when installed on a 3.6 m (12ft) ceiling.
False alarms caused by environmental disturbances are virtually
eliminated with alternate polarity pulse counter signal processing
and a low-noise pyroelectric detector.
2. SPECIFICATIONS
OPTICAL
Detection Pattern: A virtually conical pattern of maximum 10.5 m
(36 ft) diameter, when installed on a 3.6 m (12ft) ceiling.
COVERAGE PATTERNS
The DISC pattern is nearly conical (viewed from detector to the
floor). See Figure 1.
The maximum mounting height is 3.6m (12 ft). The coverage
pattern at floor level is as per the following table:
Mounting
Height
Pulse
Count 1
Pulse
Count 2
2.4m (8ft.)
3m (10ft.)
3.6m (12ft.)
7.3m diam. (24ft. diam.)
9m diam. (30ft. diam.)
11m diam. (36ft. diam.)
6.4m diam. (21ft. diam.)
7.3m diam. (24ft.
diam.)
9.1m diam. (30ft.
diam.)
ELECTRICAL
Voltage: 9 to 15.5VDC.
Current: I5mA at 12 VDC (21 mA max.).
Relay Output: Normally closed (fail-safe) contacts. 18 ohm
resistor in series with contacts. Rating - 0.1A resistive/24VDC.
Alarm Period: 2-7 seconds
Tamper Contacts: Normally closed. Rating - 0.5A resistive/
24VDC.
LED: Walk Test enabled or disabled with internal link.
Detector: Dual-element low-noise pyroelectric detector.
Pulse Counter: Two position selector, 1 or 2 pulses with
alternate polarity signal processing.
MOUNTING
Ceiling Mounting: Maximum mounting height 3.6 m (12 ft)
ENVIRONMENTAL
Operating Temperature: -10°C to 49°C (14°F to 120°F).
Storage Temperature: -20°C to 60°C ( -4°F to 140°F).
Compliance with Standards: EN 50131-1 Grade 2, Class II
PHYSICAL
Dimensions (diam. x H) : 86 x 24 mm (3-3/8 x 15/16 in).
Weight: 64 grams (2 oz)
Color: White
.
Figure 1 - DISC PIR Coverage Pattern
3. INSTALLATION
3.1 Mounting
The DISC PIR is installed on the ceiling.
The maximum installation height is 3.6m (12 ft).
A. Mount the unit so that the expected motion of an intruder is
perpendicular to the detector and not into the detector.
Be sure to install the detector on a stable ceiling, to avoid
vibrations.
Note: Passive infrared detectors are sensitive to changes in
infrared energy caused by an object moving across the unit's
field of view.
Detection of changes in infrared energy depends on the
amount of infrared energy transmitted by the moving object,
and the temperature difference between the object and the
background. Because of this the PIR may fail to respond
under certain temperature and background conditions, in
which the temperature difference is too small.
B. The DISC is extremely immune to air turbulence and RFl
interference.
However, to minimize possible
false alarms, it is highly
recommended that you avoid
aiming the detector at heaters,
sources of light, or windows
subjected to direct sunlight.
Avoid mounting the DISC in
locations where air drafts could
flow from the ceiling or from
close walls. Also avoid running
wiring close to high power
electrical cables.
COVER
BASE
Figure 2 - Removing the
Cover
C. Hold the unit base as shown in Figure 2. Rotate the cover
counter clockwise until it stops. Separate the cover from the
base.
Note: If the cover does not separate easily from the base,
insert a 1/8" screwdriver between a tab (on the cover) and a
slot (on the base). Lower the screwdriver handle until the base
separates from the cover and removes easily.