Quotes from a Fireye Insight flame scanner manual (document CU-95) that reads flame flicker frequency and radiation intensity.
Flame Quality
The “Flame Quality” number can range from 0 to 100. It represents the scanner’s 4-20 mA analog
flame signal strength OUTPUT (in percent), and is the scale by which the internal Flame Relay ON
and OFF thresholds are set.
The “Flame Quality” number is determined by the input of the IR and / or UV sensor, (in dual sensor
models it is the sum of the two). This sensor signal strength value can be viewed in the Status menu
as “Signal Strength”, see description below.
For clarity, the “Flame Quality” number is capped at 100, while under certain firing conditions the
IR or UV “signal strength” (or their sum) may normally exceed 100 (maximum of 999).
In normal burner operation after the scanner has been properly setup, “FQ 100” will be displayed
with occasional movement depending on the stability of the flame.
Signal Strength & Flame Quality (FQ), Expanded Description:
Single sensor models (Type 95IR, 95UV): The value of Signal Strength is the same as the “Flame
Quality” number except that the Signal Strength value is allowed to exceed 100 (maximum of 999)
while “Flame Quality” is capped at 100.
Dual sensor models (Type 95DS): This screen shows the individual sensor’s contribution to the
Flame Quality number. Each value is preceded by the corresponding lower case letter indicating
whether it is the IR (i) or UV (u) sensor. Under most firing conditions, the sum of these individual
values will exceed 100 (maximum of 999).