Emerson MAN -0016-00, UVC120 manual Position and Density of Detectors, Mounting the Detector

POSITION AND DENSITY OF DETECTORS

The detector has a nominal 120º cone of vision. In an application such as a loading rack with a ceiling height of 25 feet (7.5 meters) where it is desired to have complete detector coverage at floor level and a detector is mounted 2 feet (0.6 meter) from the ceiling and pointed straight down, the distance from the detector to the designated level would be 23 feet (7 meters) and because of its 120º cone of vision the detector would cover a circular area 80 feet (24 meters) in diameter at floor level. A sketch of the area to be covered will indicate the number of detectors required to monitor the area. Detectors should be placed as close as practical to the expected fire hazard.

NOTE

Do not mount UV detectors close to the ceiling of enclosed buildings if smoke might accumulate before the break-out of flame. It is preferable to mount the detectors on walls a few feet (or about 1 meter) below the ceiling where they may respond before being obscured by smoke. Consider shortening time delay settings when smoke is expected to accumulate during a fire. If dense smoke is likely to accumulate prior to flame (as in an electrical fire), supplement UV detectors with other protection.

MOUNTING THE DETECTOR

Locate detectors to ensure an unobstructed view of the area to be monitored and where accessible for cleaning the detector window and vi reflecting surface. Take care so dirt will not accumulate and obscure the detector viewing window. Detectors mounted outdoors should be pointed downward to prevent the cone of vision from scanning the horizon where long duration lightning flashes or far-off arc welding may activate the detector. To minimize dirt accumulation around the vi surfaces, mount the detectors so that the internal vi tube is on top. The silver external reflector should be placed directly over the vi tube. Refer to Figures 2a and 2b for the detector and swivel mounting assembly dimensions. Refer to Figure 10 for a diagram of the assembled detector and swivel assembly.

Figure 10 - Detector with Swivel Mount Assembly

DIP SWITCH SETTINGS

NOTE

To make DIP switch changes take effect, cycle controller power off then on.

The DIP switches on the controller circuit board must be properly programmed before applying power to the system. There are three banks of 8 position DIP switches which are OFF or ON to select area and detector combinations, controller sensitivity, fire voting logic, output latching and

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