Rockwell Automation 1771-CFM,D17716.5.99 CONFIGURABLE FLOWMET - Manual (Page 49)

4–15 Configure the CFM Module
Publication 1771Ć6.5.99 - December 1995
Value BTW word # Use to
Minimum Frequency Sampling Time 6, 16, 26, 36
determine the minimum frequency and maximum sample time. All
sample times are based on the time between F0 or F2 pulses.
If Bandwidth Limit is OFF (= 0), Minimum Frequency Sampling
Time is not used.
Bandwidth Limit 5, 15, 25, 35 (bit 14)
control the maximum time the CFM module spends calculating
a frequency and the minimum frequency that can be read by
the CFM module.
If ON: limits the maximum time period to
2 x Minimum Frequency Sampling Time and minimum
frequency to 1/Minimum Frequency Sampling Time.
Frequencies < 1/Minimum Frequency Sampling Time
are reported as stopped.
If OFF: maximum time period is 3s, minimum frequency is 1Hz
and direction can be sensed to 1/3Hz.
Minimum Frequency Sampling Time is not used.
Acceleration Calculation Time 5, 15, 25, 35 (bits 00Ć09)
specify the number of frequency samples the CFM module will
spend to calculate the acceleration value. The default value (0)
will calculate a rolling average of the previous
five samples. Since the actual frequency sample time may
vary, so does the Acceleration Calculation Time.
Acceleration Alarm 9, 19, 29, 39
determine the acceleration value that, if exceeded, will activate
the BTR Acceleration Alarm (word 4 & 5, bits 00 & 08).
RANGE: 0Ć32,767
The CFM module will not calculate an acceleration if
this acceleration value is zero.
Frequency Multiplier/Divisor 10, 20, 30, 40
scale the returned frequency and acceleration to actual
engineering units.
Frequency Multiplier must be < Frequency Divisor.
For each value RANGE: 1Ć255 DEFAULT: 1
The scaled frequency/acceleration value can not be used to
trigger any outputs (outputs triggered by frequency/acceleration
are triggered by actual frequency/acceleration).
Highest Allowable Frequency 8, 18, 28, 38
specify the highest frequency value allowed on the input
channel. When this value is exceeded, the input channel's
overspeed alarm will activate.