Bosch Appliances D296/D297 manual Transmitter Receiver Ceiling beams joists, Slope 10 or less

If the ceiling beams (joists) exceed 1 ft (.03 m), the spacing between the beams exceeds 8 ft (2.4 m) or the ceiling height exceeds 12 ft, the detectors must be located in every ceiling beam pocket.

Transmitter	Receiver
	Ceiling beams (joists)
Transmitter	Receiver

Transmitter Receiver

If the fire size is expected to exceed 1-MW (1000 KW), the ceiling height may be up to 28 ft before each beam pocket must be treated separately. It is recommended that you review Section B-2Performance-Based Approach to Designing and Analyzing Fire Detection Systems in NFPA 72® , National Fire Alarm Code® (2002 Edition) to determine the potential fire size at the locaton.

6.6.2 Sloped Ceilings

Beamed ceilings with beams running parallel to (up) the slope, the spacing for flat beamed ceilings should be used. The ceiling height is considered the average height over the slope. For slopes greater than 10 degrees, the detectors located at one-half the spacing from the low end are not required. Spacing will be measured along a horizontal projection of the ceiling. For beamed ceilings with the beams running perpendicular to (across) the slope, the spacing for flat beamed ceilings should be used. One set of beams must be within 3 ft (1 m), measured horizontally, of the high point of the ceiling.

3 ft.

(1 m)

Max.

S

S

½ S

Slope 10° or less

3 ft.

(1 m)

Max.

S

S

Slope greater than 10°

Detector at ½ S not Required

D296/D297 Series Application Guide 9