Reflector
Tx RX
S
S
3 ft. (0.9m)
maximum
3 ft. (0.9m)
maximum
Refer to loca
l regulations
for
installation d
epending on
height of roo
f
Figure 3-6: Sloped Ceiling (Peaked Type)
Example for spacing according to NFS
61.970 and the installation rule R7
The detectors must be positioned at a distance h2 corresponding to the height
under the ceiling
In the following table, you will find the requirements specified by NFS 61-970
and the installation rules R7 of the APSAD, the latter varying according to the
height h1 of the protected space. Distances h2 are given for flat ceilings.
These values will vary depending on the geometry of the room and the
specific installation conditions.
Hauteur du local h1 en m
Height of installation under ceiling h2 in
m
h1 ≤ 5
0.3 < h2 ≤ 0.5
5 < h1 ≤ 12
0.5 < h2 ≤ 2
12 < h1 ≤ 15*
0.5 < h2 ≤ 3 for the higher level
* When the room height is greater than 12 m, the risk analysis may lead to
installing a second level of detection.
The maximum monitoring width l also depends on the height of the room, and
is defined in the table below.
Height of room in m
Maximum width of surveillance I1 or I2
in m (see drawing below)
h1 ≤ 5
4
5 < h1 ≤ 12
5
12 < h1 ≤ 15*
5
R
E
l
l1
l2
1
Figure 3-7: Supervised Area
Each detector positioned according to the drawing above is able to monitor a
floor area (A) varying with the height of the room (h1). This surface is in the
form of a polygon rectangle of width (l = l 1 + l 2) and length (L). This
method is applicable for risks with flat or sloped roofs. In the latter case, the
height of the room is measured at the highest point.
For more information about installation requirements, refer to the standard
NFS 61- 970 or the APSAD R7 Installation Rule.
Mounting Locations
Beam detectors require a stable mounting surface for proper operation. A
surface that moves, shifts, vibrates, or warps over time will make the system
prone to nuisance alarm or trouble conditions. Initial selection of a proper
mounting surface will eliminate false alarms and nuisance trouble signals.
Mount the detector on a stable mounting surface, such as brick, concrete, a
sturdy load- bearing wall, support column, structural beam, or other surface
that is not expected to experience vibration or large movement over time. DO
NOT MOUNT the beam detector on corrugated metal walls, sheet metal
walls, external building sheathing, external siding, suspended ceilings, steel
web trusses, rafters, non-structural beam, joists, or other such surfaces.
In cases where only one stable mounting surface as defined above can be
used, the transmitter/receiver unit should be mounted to the stable surface and
the reflector should be mounted to the less stable surface. The reflector has a
much greater tolerance for the unstable mounting locations defined above.
Mounting Instructions
Mounting the Reflector
The reflector can be mounted to the wall using the supplied drilling template
see (
Appendix II. Reflector Drilling Template
). The reflector has 4 mounting
holes, one in each corner.
All four- hole locations should be used to provide a secure mounting. The
reflector must be mounted such that it is within 10° in both the X and Y planes
of the transmitter/receiver unit. See Figure 3-8 and Figure 3-9. The reflector
must also be mounted such that the plane of the reflector is perpendicular to
the optical line of sight to the transmitter/receiver unit. The maximum
tolerance for non-perpendicular mounting locations is 10°. See Figure 3-10.
If the reflector cannot be mounted within 10° of the transmitter/receiver unit
then the multi-mount kit (6500MMK) may be used to provide greater angular
adjustment of the transmitter/receiver unit. If the perpendicular plane of the
reflector cannot be mounted within 10° of the optical line of sight then the
multi-mount kit can be used for the reflector.
WALL
Y
Reflector
10°
10°
Acceptable mounting
locations for reflector
X
Figure 3-8: Reflector Mounting Guidelines
8
E56-6965-000
