Avoid Bright Light Sources; Use Correct Wire Gauge And Length; Provide A Stable Mounting Surface - Bosch D296 Installation Instructions Manual

Long-range Beam Smoke Detectors
3.2

Avoid bright light sources

Bright light can cause stray signals. Do not point the receiver toward any of the following
sources.
Sunlight: Do not point the receiver directly at the rising or setting sun. If installing the receiver
where sunlight cannot be avoided, mount it slightly higher than the transmitter and aim it
down toward the transmitter. This causes the receiver to look below the horizon.
Bright Lights: Do not mount the receiver where it looks at exposed bulbs of high-pressure
sodium, mercury vapor, and metal halide lights. For an illustration of areas in which to avoid
exposed lights, see the following figure.
Figure 3.1: Avoiding Exposed Lights
Bare fluorescent lights can also create a problem, especially in long hallways where a series of
lights are perpendicular to the beam. Incandescent lights are not a problem as long as they
are not directly in the beam path.
3.3

Use correct wire gauge and length

Beam smoke detectors are often used to protect large areas, requiring long wire runs to
power the detectors and signal alarm conditions. The voltage available at the end of long wire
runs might not be sufficient to power the detector, especially when the system is running on
backup battery power. Use the correct wire gauge when installing detectors.
For the proper number of transmitter and receiver pairs depending on wire size and length,
see the following table.
500 ft (152 m)
1000 ft (304 m)
2500 ft (762 m)
5000 ft (1524 m)
Table 3.1: Wire Gauge and Length
3.4

Provide a stable mounting surface

Beam smoke detectors depend on the projected beam measurement to sense smoke. Trouble
or alarm conditions can be caused by shifts in beam alignment when the transmitter or
receiver moves.
Bosch Security Systems, Inc.
1 Receiver
Wire Length
Installation Instructions
14 AWG
(ISO 2.5 mm )
2
20 pairs
10 pairs
4 pairs
2 pairs
2 Do not place bright lights in this area.
Wire Size
16 AWG
(ISO 1.5 mm ) (ISO 0.75 mm
2
13 pairs
6 pairs
3 pairs
1 pair
2014.01 | 06 | F.01U.068.899
Notices | en 7
14 AWG
)
2
8 pairs
4 pairs
2 pairs
1 pair