ACES SYSTEMS Cobra II, Руководство пользователя

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Gen II
User Manual
13-10 – Transient Vibration Survey Chapter 13 Revision 4.10, Apr 20
To define Speed inputs, do the following:
13.1.1.4.1. In the “ Measure ” column, use the [

] or [

] key to select from “Pulse S”, “Pulse D” or
“None” indicating the tachometer input type for the tachometer input channel indicated.
NONE is selected when the corresponding tach channel is not being used. Only pulsed
inputs such as a Phototach, Lasetach or magnetic pickup may be used with the Viper II
Analyzer. This pulse input may be, but is not necessarily a once-per-rev pulse. The
preference is actually a multi-pulse per revolution input. The D or S in the selection
depicts either single ended (S), which supplies power to the output for use with a
Phototach or Lasetach, or differential (D), which does not supply power at the tach device
for use with a magnetic pickup or monopole.
13.1.1.4.2. The “ DESC ” column is the descriptive name for the tachometer input such as “N1”,
“N2”, or “Fan”. Enter up to five alphanumeric characters in this field. The description
should be one that all users of this setup are familiar with and easily understand.
13.1.1.4.3. The “ 100% Spd ” column is used to enter the rpm at 100% of component speed. Use the
keypad to enter the value in the “100% Spd” field. The example above shows “4800” and
“10000” for “N1” and “N2” respectively. This will cause the analyzer to also display the
component speed in percent during data acquisition. Therefore, when used on an engine
spool, N1 or N2 for example, the analyzer’s indication will match the cockpit indicator.
An example can be found below in paragraph 13.1.8 below.
13.1.1.4.4. The “ FACTOR ” column can be used to enter a multiplier for converting Hertz to actual
component speed in RPM. If using a Pulse input, the RPM is equal to Hertz x Factor. The
analyzer assumes the input to be relative to Hz (cycles per second) so that an input of one
pulse per revolution (one-per-rev) would require a FACTOR of 60 (1 per-rev X 60 Hz
assumed) to equal Revolutions Per Minute (RPM). Enter the factor using the keypad. The
example above shows a factor of “60” for the “N1” to represent the usage of a
“LaseTach”. When sampling multiple pulses per revolution, you must know the tach