Section 3 — Sensors
44
Semi-automatic Keyphasor Threshold Selection
If a recording is tach-triggered but no pulses are being detected, your
instrument will prompt you to select the appropriate Keyphasor
threshold.
If you are performing a Tachometer Display measurement, you can also
bring up the same semi-automatic selection screen. To do this:
1. Press or Measure.
2. Select Tachometer Display > Press .
3. Press Tach Threshold — Your instrument scans through the
3V, 8V, 13V, and 18V threshold levels, displaying the RPM value
detected at each one.
4. Use the keys provided to select the threshold that delivers a stable
RPM reading and matches the expected speed of the machine you
are testing — The threshold value you selected will be used for all
subsequent recordings on the machine you are measuring.
NOTE: Your instrument will increase the duration between
thresholds to find lower RPM values. This process can take just
over a minute. A value of zero will display if there is no RPM value.
Correcting the threshold setting for your tachometer and machine