ACES SYSTEMS Cobra II, Руководство пользователя

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Gen II
User Manual
15-8 – Overall Vibration Survey Chapter 15 Revision 4.10, Apr 20
15.1.1.3.4. 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
pulse frequency (Hz) of the tach source at 100%. The component speed (RPM) at 100%
is then divided by the tach pulse frequency to obtain the factor. In the example above, the
“N2” speed at 100% is 10,000 RPM and the tach pulse frequency is 4000 Hz. This will
give us a factor of “2.5”. If the tach pulse frequency is unknown, set the FACTOR to “1”
and read the value for the applicable tach channel at a known stable engine speed. The
indicated tach pulse frequency can then be divided into the known engine speed at that
point. For this purpose, it is recommended to use the analyzer’s “Monitor Overall”
function (see Chapter 19) as it is quick and easy to configure.
15.1.1.3.5. Use the [

] key to select the “ Tach Filter Type ”. The options are for a Single pole
filter, a Double pole filter or None.
15.1.1.3.6. Use the keypad to enter the “ Tach Filter Frequency ”. Enter a numeric value equal to
the lowest frequency of interest. The filter will then be effective for that frequency and
all frequencies above that value.
15.1.1.3.7. Repeat paragraphs 15.1.1.3.1 through 15.1.1.3.46 for each of the channels required.
When all fields are completed per your requirements, press the [OK] key to return to the
setup screen.
15.1.2. – Job Identification
The next screen displayed is the “Job Identification” banner screen shown in the following
illustration. All information on this screen is optional; however, we highly recommend you fill in
as much information as possible to ease the task of storage and retrieval of surveys. If you have
entered names or registrations into the analyzer previously, you may press the [F1] “Cust” or
[F2] “A/C Reg” key to select from a list of stored customer names or registrations, which will
then be entered into the “Customer” or “A/C Registration” fields. When all desired fields are
complete, press [OK] to continue.