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Performance – Spectrex 20/20R - Single IR Flame Detector User Manual

Page 12

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Spectrex Inc. - SharpEye

TM

Single IR Flame Detector Manual – TM 20/20R, Rev. A January2005

4

3. Performance

3.1 Detection Sensitivity
Detection sensitivity is the maximum distance at which the detector will reliably
detect a specific size of fire & typical type of fuel (standard fire).

Standard Fire:
A 1ft x 1ft (0.3m x 0.3m) Gasoline pan fire with max. wind speed of 6.5 ft/sec
(2 m/sec).

Sensitivity Ranges:
The detector has two user selectable sensitivity ranges. For each range there are
two response levels.

1. WARNING (Pre-alarm)
2. ALARM


The detection distance, for the WARNING level, is approximately 10% higher than
the ALARM distance. Alarm response times for a “standard fire” at a specified
range are shown hereunder.

Table 1: Alarm Response Time Versus Range

Sensitivity

1

2

Range – ft (m)

15 (5)

50 (15)

Response Time (sec)

5 10

For some typical ambient conditions the Zeta parameter as defined in NFPA 72 for
the detector is 0.005 (1/meter).

Note:

Zeta parameters may vary significantly with changes in temp, air pressure,
humidity, visibility conditions, etc.