Setting The Rpm - Commtest Instruments vbBalancer Instrument Reference Manual

Store Units
Acceleration
Velocity
Displacement
Store Units
Acceleration
Velocity
Displacement
vdB
The vibration velocity level vdB is defined as 20 times the logarithmic
of the ratio of the RMS velocity level to a reference velocity value
(the vdB reference). The value 1e-6 mm/s is an abbreviation for
-6
1x10 mm/s and is the SI reference level. The value 1e-5 mm/s is
the reference level used by the US Navy and many American
industries.
adB
The vibration acceleration level adB (US) is defined as 20 times the
logarithm of the ratio of the RMS acceleration level to 1 µg RMS.
The SI version of adB is less commonly used, and has a reference
value of 1 µm/s

Setting the RPM

Setting the 1X RPM allows you to view the chart in orders (for
spectra) or revs (for waveforms). You can enter the RPM manually (if
you know it), or set the RPM from a spectral 1X peak.
Entering the RPM manually
With a measurement displayed press
•
RPM.
Max dB Value
Linear Scale
2 2
m/s , mm/s
mm/s, µm/s
mil, mm, µm
Y Axis Fixed
Linear Scale
automatic, current, mm/s
automatic, current, µm/s
automatic, current, m
2
.
Section 6: Analyzing Measurements Onsite
Max dB Value
Log Scale
2
m/s , mm/s
mm/s, µm/s
mm, µm
Y Axis Fixed
Log Scale
2 2
m/s , mm/s
mm/s, µm/s
mm, µm
then
2
2
Set
69