Monarch Instrument Nova-Strobe vbx - Manual (Page 15)

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4.3 External Input Mode
In the External Input Mode the user can’t make any flash rate adjustments.
The flash rate is a function of the input signal. This mode is used to
synchronize the flash to an external event (for example, from an optical
sensor) to stop or freeze motion. The flash will be triggered on the rising or
falling edge (menu selectable) of the external input pulse.
To put the strobe into the External Input Mode, connect a signal to the
external input and press the INPUT button on the display panel until
EXT is displayed.
4.4 Tachometer Mode - External Input Required
When an external input is supplied to the unit and the strobe is put in the
Tachometer-External Mode, the unit will read the signal from the external
input (sensor) and display the reading on the LCD display without flashing
the lamp. The strobe will not flash in the Tachometer Mode.
To enter the Tachometer-External Mode:
1.
Press the INPUT button until EXT is displayed.
2. Press the ALT FUNCTION button and then the TACH button.
The TACH icon will be displayed.
NOTE: If the external input signal exceeds the maximum flash rate,
the strobe will go into the Tachometer Mode automatically.
To exit the Tachometer-External Mode:
1.
Press the ALT FUNCTION button and then the TACH button.
The TACH icon will go away.
2. The unit will remain in the External Input Mode unless the INPUT
button is pressed to change the mode.
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Connect the proper interface cable between the strobe and the data collector
or analyzer. See wiring diagram to build the cable. The Input (Up Arrow)
and Output (Down Arrow) jacks are located on the left side of the strobe.
Connect the vibration transducer (this may be a separate cable or an
integral cable) to the strobe cable.
NOTE: The vibration transducer provides the signal the strobe uses as
a phase trigger source and therefore is the input to the strobe.
The vibration transducer also provides the vibration signal to
the data collector or analyzer. The interface cable provides a
“TEE” connection to both. The strobe provides the phase
referenced tachometer signal (output), which is used as a TTL
input to the data collector or analyzer for triggering.
Now you are ready to go to work!
Follow the operating instructions outlined at the beginning of this section
for tuning the strobe to 1X running speed. After the reference mark has
been “frozen” (as nearly as possible, but slight rotation is acceptable).
Press the Input/Memory button until the LOCK icon is on. The flash rate
is now derived from the vibration transducer. Phase information is only
valid when operating in the LOCK mode.
Press the Phase Delay button until PHASE is shown on the display. Using
the control knob, position the reference mark to a “convenient reference
location”. The data collector can now be employed to receive and process
the phase information as supplied to it by the strobe and the transducer.
After the information is received, simply release the trigger on the strobe,
proceed to the next point, and then repeat the process.
NOTE: The trigger must stay depressed until the data collector or
analyzer is through processing the data.
For certain data collectors that do not provide constant power out to
transducers that so require, it may be necessary to command the analyzer
to begin taking the data before the phase image becomes stable enough to