Det-Tronics PM-5MP & PM-5MP+ Dual Spectrum IR Flame Detector - Manual (Page 6)

FALSE ALARM IMMUNITY
The PM-5MP and PM-5MP+ are highly resistant to false
alarms. However, no flame detector is perfect — a fire
alarm output due to non-fire stimuli is possible. Table 3
lists common stimuli and the false alarm immunity dis-
tance for those stimuli, as tested by Factory Mutual
Research. No false alarms occur for larger distances in
laboratory measurements.
For best performance, the detector should be mounted
so that any exposure to these sources occurs at dis-
tances at least as large as those given in Table 3. In
addition, to ensure optimum performance, detectors
should be mounted so that they do not view very bright-
ly illuminated areas. For example, indoor mounting loca-
tions where the detectors look out doors or windows
should be avoided wherever possible.
DETECTOR INSTALLATION
PHYSICAL MOUNTING
The PM-5MP and PM-5MP+ must be installed in confor-
mance with the appropriate drawing provided in this
manual, NFPA-72, the NEC, and all local codes for the
hazard classification of the location to be protected. The
detectors come with an integral multi-conductor cable
for the alarm and power circuits.
CAUTION
The factory sealed front cover is essential to the
approval of the detectors. Removing this cover will
compromise the performance of the detector.
The compact package of the PM-5MP and PM-5MP+ is
of great benefit in applications where space is a limiting
factor. It has four holes in the mounting flange that can
be used to mount the detector directly to a flat surface or
bracket. Take care not to over-tighten mounting hard-
ware.
The number of detectors required to protect a given area
will depend on the size of the area, the distance from the
detector and the size and type of the fire threat. Certain
factors need to be considered when designing an instal-
lation:
1. The detectors should be mounted so that objects do
not block their field of view. This includes glass,
plexiglass and other visibly transparent materials.
2. Whenever possible, detectors should be mounted
so their ranges and fields of view overlap.
3. Detectors should be mounted so they will not be
blocked by moving machinery or personnel during
normal operations within the area.
4. To ensure optimum sensitivity and performance,
detectors should be mounted so they do not view
brightly illuminated areas.
5. The detectors should be mounted so that they are
easily and safely accessible for inspection and
maintenance.
6. If mechanical or high-temperature damage, or win-
dow contamination is likely in the installed location,
then the detectors should be protected. However,
the protection method cannot obstruct the detector’s
field of view with any material, including visibly trans-
parent materials like glass and plexiglass.
7. The detectors can be mounted in any orientation, so
long as the manufactured mounting points are the
point of support.
8. Mounting the detectors so that they point below hor-
izontal is recommended, as this generally results in
minimal window contamination. When practical
mount the detector with the cable entry pointing
below horizontal.
ELECTRICAL WIRING CONNECTION
An approved installation of the PM-5MP and PM-5MP+
flame detectors must be in accordance with the FM
Approved drawings included as appendices to this man-
ual and all local codes. The required drawing for specif-
ic hazardous (classified) or non-hazardous locations can
be determined from the Control Drawing Configuration
4
Table 3—False Alarm Immunity Distances
(Factory Mutual Research Verified)
Stimulus PM-5MP PM-5MP+
(Modulated or Unmodulated) Medium High
Sensitivity Sensitivity
Range (in) Range (in)
Sunlight through Glass No Response No Response
Flashlight (3 D-Cell Maglite) No Response No Response
Vehicle Headlight 12 12
Electronic Flash (Sunpak 411/Vivitar 5200) 6 6
Arc Welding (5/32” Steel Rod, 140 A) 30 40
Radiant Heater, Quartz (1500 W) 48 62
Brightly Colored Clothing No Response No Response
Fluorescent (40 W / 68 W) No Response No Response
Incandescent Light (100 W Frosted) 3 3
Flood Light 36* 72**
Sodium-Vapor Lamp (70 W / 250 W) 3 3
Forced Air Heater (1500 W) 24 24
*Sungun-II, 650 W
**Nite Tracker, Quartz Halogen, 1.5 M Candlepower