Bosch D296 Application Manual page 7

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2.5.3 Peaked Ceilings
Peaked structures follow the same guidelines as sloped ceilings with one exception. When calculating the location
of the detectors, the first detector is within 3 ft (1 m) of the peak (measured horizontally). Space additional
detectors down from the detector nearest the peak. Refer to Figure 8.
Figure 8: Peaked Ceilings
1 - 3 ft (1 m) maximum
S = Selected detector spacing
2.5.4 Long Ceilings
Long ceilings over 350 ft (107 m) require more than
one set of detectors to cover the entire length.
Determine the number of detector sets by:
1. Dividing the ceiling length by 350 ft (107 m)
and rounding up to the nearest number.
2. Placing the detector sets to cover an equal
amount of area.
Figure 9: Long Ceilings
1
2
3
3
100 ft
(30 m)
2
1 - Alternate transmitter and receiver locations in
multiple unit installations
2 - Transmitters (2)
Bosch Security Systems, Inc. | 01/07 | F01U500951-01
S
3
L
4
2
25 ft
(7.5 m)
50 ft
(15 m)
25 ft
(7.5 m)
300 ft (91.5 m)
D296/D297 | Application Guide | 2.0 Applications
1
S
3. Setting the transmitters and receivers to the right
and below to avoid possible cross talk (Figure 9).
4. Setting the minimum spacing between adjacent
detectors to L/10 the distance between the
transmitter and the receiver. For example, the
minimum spacing for a beam length of 300 ft
(91.5 m) is 30 ft (9 m).
2
3
300 ft (91.5 m)
600 ft (183 m)
3 - Receivers (2)
4 - L/10 minimum; 60 ft (18 m) maximum
3
2
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