beautypg.com

Performance – Spectrex 20/20MI - Mini Triple IR (IR3) Flame Detector User Manual

Page 17

background image

Spectrex Inc. - SharpEye

TM

Mini IR3 Flame Detector Manual – TM 787100, Rev. D April 2011

9

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

2

(0.1m

2

) Gasoline pan fire with max. wind speed of 6.5 ft/sec (2 m/sec).


Sensitivity Ranges:
The detector has four 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 – 20/20MI-1

10

20

30

40

Sensitivity Range – ft (m) 33 (10)

65 (20)

100 (30)

132 (40)

Response Time (sec)

5 8 10 10

Table 2: Alarm Response Time Versus Range – 20/20MI-3

2.5

5

7.5

10

Sensitivity Range – ft (m) 8.2 (2.5)

16.5 (5) 24.7 (7.5)

33 (10)

Response Time (sec)

1 1 2 3


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.