Figure 5b. Reflector Mounting Guidelines
10ϒ maximum
optical line of sight
REFLECTOR
C0259-00
Mounting Considerations for Single Ended Beam
Detectors
There must be a permanent clear line of vision between the
detector and the reflector. Reflective objects must not be
near the line of vision between the detector and reflector.
Reflective objects too near to the line of sight can reflect
the light beam from the transmitter to the receiver. If this
occurs, the detector will not be able to distinguish these
reflections from those of the reflector and the protected
space will be compromised. Reflective objects should be
a minimum of 15 inches (38.1cm) from the line of sight
between the detector and reflector. In cases where reflective
objects cannot be avoided, the complete reflector blockage
test can be used to determine if the installation is accept-
able. See Testing and Maintenance Section of this manual.
Light sources of extreme intensity such as sunlight and hal-
ogen lamps, if directed at the receiver, can cause a dramatic
signal change resulting in fault and alarm signals. To prevent
this problem direct sunlight into the transmitter/receiver
unit should be avoided. There should be a minimum of 10°
between the pathway of the light source and detector and
the line of sight between detector and reflector.
Operation of the detector through panes of glass should
be avoided. Since single ended beam detectors operate on
a reflection principle, a pane of glass perpendicular to the
line of sight between the detector and the reflector can
reflect the light beam from the transmitter to the receiver.
If this occurs, the detector will not be able to distinguish
these reflections from those of the reflector and the pro-
tected space will be compromised.
Panes of glass will also absorb some of the light as it
passes through it. This absorption of light will reduce the
acceptable installed distance between the detector and the
reflector.
In cases where operation through panes of glass cannot
be avoided some specific installation practices can help to
minimize the effects of the glass. These practices include:
avoid penetration of multiple panes of glass, position the
glass so that it is not perpendicular to the line of sight
between the detector and the reflector, (A minimum of 10°
off perpendicular should be considered), and make certain
that the glass is smooth, clear and mounted securely. The
complete reflector blockage test can be used to determine if
the installation is acceptable. See Testing and Maintenance
Section of this manual.
Where high ceilings (in excess of 30 feet or 9.1 meters) are
present additional beams may be required to detect smoke
at lower levels.
Wiring Installation Guidelines
Always install all wiring in compliance with the National
Electrical Code, and/or the applicable local codes, and any
special requirements of the local authority having jurisdic-
tion. Proper wire gauges and suitable means for strain relief
should be used. The conductors used to connect beam
smoke detectors to control panels and accessory devices
should be color-coded to reduce the likelihood of wiring
errors. Improper connections can prevent a system from
responding properly in the event of a fire.
Installation wire used for the beam detector shall be no
smaller than 22 AWG (1.0 mm
2
). For best system perfor-
mance, all wiring should be twisted pair and installed in
separate grounded conduit. Do NOT mix fire system wiring
in the same conduit as any other electrical wiring. Shielded
cable may be used to provide additional protection against
electrical interference.
When installing the beam smoke detector in applications
where the head unit will be mounted to either a wall or
the ceiling using the multi-mount kit (BEAMMMK) flexible
conduit will be used. The surface mount kit (BEAMSMK)
and multi-mount kit (BEAMMMK) must be installed with
the cable before wiring the unit, according to the instruc-
tions supplied with the kit.
When the detector has been mounted over a recessed junc-
tion box, all wiring should be routed out of the box and
behind the detector to the bottom of the detector where
the terminal blocks are located. When installing the wir-
ing in the junction box be sure to leave enough wire in the
box to connect to the terminal blocks. (Approximately 9″
(23cm) of wire outside of the junction box will be required
for proper installation). All wiring to the detector is done
via pluggable terminal blocks. In order to properly make
electrical connections strip approximately
1
/
4
″ (6mm) of
insulation from the end of the wire, sliding the bare end of
the wire under the clamping plate screw.
Figure 6 shows all the wiring connections to the transmitter/
receiver unit. Figure 7 shows the proper wiring diagram for
either class A or class B operation. Figure 8 shows the con-
nections that are necessary when using one of the optional
N200-25-00 6 I56-2424-04R
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