Fi Frequency Input - Honeywell HC900 Reference Manual

FI Frequency Input

Description
The FI label stands for Frequency Input .
This block is part of the I/O Blocks category.
Function
The function is used for measuring speed and rate. It reads a single frequency channel from a
Pulse/Frequency/Quadrature input module. The signal is scaled from the selected frequency span to the
selected output range in engineering units, providing an output value in engineering units.
The input signal is rejected if it is below a selected pulse width. The frequency of pulses above this width
must be within the range specified by Pulse Width (Range); otherwise the output goes to failsafe and a
failure-to-convert error occurs.
Input
ENABL = Level input to enable block. Input is ignored if not connected and default state is enabled. If
block is disabled the output goes to zero.
Output
FAIL = A Boolean value that turns ON when the Pulse/Frequency/Quadrature input module reports a
failure.
OUT = The frequency input value scaled to engineering units (after filters, ranges, bias, or failsafe
conditions have been applied).
⎛
Frequency
⎜
=
OUT
⎝
Frequency
The generic forcing of outputs is permitted.
Revision 11
2/07
In - Frequency Span Low
Span High - Frequency Span
HC900 Hybrid Control Designer Function Block Reference Guide
⎞
(
⎟
*
Output EU High - Output
⎠
Low
Function Blocks
FI Frequency Input
)
+
EU Low Output EU Low
+
Bias
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