Fireye 85IRF series, Руководство пользователя

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Advanced Parameter Programming - Trip Threshold Adjustment
The scanner provides advanced programming for select parameters to enhance functionality. The adjust-
able parameters are:
• Average Amplitude
• Power Spectrum Density
• Best Fit
• Peak-to-Median Ratio
Only the trip threshold for these parameters can be adjusted. Once the parameter of interest is selected, the
keypad is used to increment the trip threshold up or down to the desired setting using the LEDs as a guide.
Blinking LEDs represent a single increment and solid LEDs represent two increments. Table 8 provides a
description of each adjustable parameter, its programmable range and the corresponding increments and
LED display.
Table 9: Adjustable Parameters and Corresponding Increments / LED Display
Adjustable
Parameter
Default Program
Setting
Programmable
Range
Individual
Increments
Blinking LED
Program
Increment
Solid LED
Program
Increment
Average
Amplitude
The Average Amplitude setting is a percentage of the learned flame’s average amplitude. The percentage is
used to calculate the threshold of the minimum value required to prevent a flame OFF event.
25% 5% to 80% 5% 5% 10%
Power
Spectrum
Density
The Power Spectrum Density setting is a percentage of the learned flame’s power spectrum density. The
percentage is used to calculate the threshold of the minimum value required to prevent a flame OFF event.
12.5% 2.5% to 40% 2.5% 2.5% 5%
Best Fit
Ratio
The Best Fit Ratio setting represents how well the monitored flame matches the learned flame. A high relative
value reflects a good match, while a low value would be a poor mismatch. The setting establishes a trip
threshold required to prevent a flame OFF event.
Note: The best-fit-ratio programmable trip threshold has a
base of 15 counts which is added to the value determined from the LEDs.
Ex. Two solid LEDs (2x32) and one blinking LED (1x16) = 15 (base) + 64 + 16 = 95 counts.
175 counts
31 to 217 counts
(base count = 15)
16 counts 16 counts 32 counts
Peak-to-
Median
Ratio
The Peak-to-Median Ratio setting represents the ratio of peak amplitudes to the median amplitude of the
monitored flame. The lower the count, the closer the median amplitude is to the peak amplitude. Lower counts
are typical of a flickering flame. Higher counts are indicative of an incandescent or fluorescent light source.
The setting establishes a trip threshold required to prevent a flame OFF event.
25 counts 5 to 80 counts 5 counts 5 counts 10 counts