How Alarm Point Location Works
The Protectowire Alarm Point Location Meter, an exclusive feature of Protectowire FireSystem control panels, is designed to locate a heat actuated point on a length of Protectowire Linear Heat Detector. The Meter provides a means to display the alarm point location, represented as a linear distance in Feet or Meters, from the start of the Protectowire portion of the circuit to the heat actuated alarm point on the detector.
How Alarm Point Location works
Alarm Point Location is made possible by Protectowire Linear Heat Detectors electrical resistance characteristic. The detectors steel conductors have a high resistance per foot compared to the copper feed wires connecting the detector to the control panel. This resistance can be measured and used to determine the length of the detector.
Each Protectowire zone is field calibrated after installation to eliminate copper feed cable resistance from the Alarm Point Location reading. This is done by manually shorting the detector at the beginning of the zone and adjusting the display to zero "0000".
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Alarm Point
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When an overheat (alarm) occurs in a zone, an alarm point reading is taken either *manually or *automatically at the control panel. This reading represents the linear distance to the actuated point along the detectors length.
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Alarm Point
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| * = Determined by control panel type and options ordered | |
Zone Mapping
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When a Protectowire Linear Heat Detection System using the Alarm Point Location Meter is first brought online, points along the detector correlating to a floor plan or installation detail can be temporarily shorted an measured. Each distance reading can then be marked on the floor plan or detail at it's corresponding point. In the future, a reading of the Alarm Point Location Meter can be referenced on the floor plan or detail, making location of the overheated (alarm) portion of the wire easier to locate. |