IDD Frequency Ranges
The Frequency Ranges allow the user to specify one or two discrete frequency ranges for inclusion into
the IDD output signal level for pick-up and dropout comparisons. Each frequency range is defined by its
lower and upper corner frequencies. Weight factors are also available to allow an imbalanced ratio of
signal energy to be included from two ranges if desired. A single range is adequate to produce the low-
pass, high-pass, or band-pass filter functions.
Additionally, two frequency ranges can be used to do combinations of low-pass, high-pass, and band-
pass filter functions. This feature is available to produce a notch filter function if a difficult application
requires this option.
The incoming detector head signal may be tuned in 1 or 2 ranges. The ranges cover from 12Hz to
1024HZ. The system defaults to 1 range. If 2 ranges are chosen, adjust them both, upper and lower
ends, but NO overlapping of frequencies is allowed.
Press F1 - CHG then type “2” (to change from 1 range to 2 ranges)
Press F4 – NXT
Note:
Because the IDD signal is monitored from the A/D converter output for the purpose of setting the GAIN,
(ahead of the band-width filters and weights) any subsequent adjustments to the corner frequencies
or weighting factors will not affect the GAIN setting. If the flame detector is adjusted or replaced, the
GAIN setting will need to be rechecked.
15
372001-24 Rev. A
IDDX Flame Detector Amplifier Manual