Monarch Instrument Nova-Strobe vbx - Manual (Page 11)

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5. Turn the black tuning knob to edit the menu option.
6. Press the MENU button to save your changes. Press any other button
to cancel.
7. Press any button other than MENU to exit the Main Menu.
8.
DONE will be displayed.
Below is a list of the menu items:
D E C P T D E C P T D E C P T D E C P T D E C P T - Decimal Point (none, 1 or 2)
B L I T E
B L I T E B L I T E B L I T E B L I T E- Backlight (Yes=On or No=Off)
I N P U T
I N P U T I N P U T I N P U T I N P U T - Positive (pos) or Negative (neg) Edge for Input Signal
O U T P T
O U T P T O U T P T O U T P T O U T P T - Positive (pos) or Negative (neg) Edge for Output Signal
B L A N K
B L A N K B L A N K B L A N K B L A N K - Input Blanking (Yes=On or No=Off), see section 6.0
A C C E L
A C C E L A C C E L A C C E L A C C E L - Select 10mV/g or 100mV/g for the accelerometer sensitivity
A N A L Z
A N A L Z A N A L Z A N A L Z A N A L Z - Select YES if an analyzer is being used to power the
accelerometer or NO if the strobe to power the accelerometer.
4.0 OPERATION
To turn on the stroboscope, depress and hold the trigger. The trigger may be
locked in position using the side locking button. To lock the stroboscope
on, depress the trigger as far as it will go and then press the locking button.
Once the locking button is set you may release the trigger and the trigger will
be held in place. To unlock the stroboscope, simply depress the trigger and
then release.
There are five operating modes for the Nova-Strobe vbx. These are Internal,
External Input, External Phase Delay, External Time Delay, and Auto (Virtual
RPM). All but the Internal Mode require an external input signal.
In the Internal Mode the knob adjusts the flash rate. In the External
Input Mode an external signal is used to trigger the flash and the knob has
no effect. The External Delay Modes (Phase, Time and Auto) enable the
For these tests the strobe light should be set on a tripod. A long cable
will be needed for the sensor. The sensor should be mounted on a
magnetic base.
Follow the same 5 steps outlined in the previous section for General
Preparation for phase analysis, and then follow these steps:
1. Mark the piping system off in given intervals and note the location of
supports or hangers. For example, use 6-foot intervals. Draw a
simple diagram on paper.
2. Start at the machine end, adjust the strobe light to running speed, and
note the phase reading using the clock face method. (For reference,
adjust the phase marker to the 12:00 o’clock). Move the vibration
transducer to each location, noting the phase reading at each.
NOTE: Do not move the strobe, just the vibration sensor. Do not
change the Phase Angle control knob after the initial reference
has been set.
3. The phase markings should “walk” around the clock face as the
sensor is moved to each location. Each time the marking is at or near
12:00 o’clock, the motion is at or near maximum and is in phase with
the reference point. Each time the marking is at or near 6:00 o’clock,
the motion is at or near maximum in the opposite direction and is out
of phase with the reference point.
6.0 LIMITATIONS OF REMOTE OPTICAL SENSORS
Remote Optical Sensors have a slight limitation when used with the Nova-
Strobe vbx because they sense not only the reflective marker but the strobe
flash as well. If the ROS is positioned near the strobe, the light from the strobe
may cause the ROS to trigger the stroboscope at the wrong time, especially
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