Shock pulse measurement
D:23
D
Using the earphones
For dBm/dBc, earphones can be used to listen to the shock pulse
pattern in case of suspect or high readings. Listening to the shock
pulse signal can help to pinpoint the cause for high values. This,
and the possibility to search for shock pulse sources with the probe
transducer, is a means to verify the measuring result and its cause.
Earphone listening does not work with the LR/HR and SPM HD technique.
The measuring threshold is changed with the UP/DOWN arrow keys
on the Leonova keypad. At a low level, Leonova will emit a continuous
tone. As the threshold is raised, this changes to very rapid pulses at
the dBc level. At the dBm level, only a few pulses should occur at
irregular intervals.
Significant are
• the dBm level
• the rhythm of the pulses immediately below the
dBm
level
• the delta value, which is the difference between the dBm and the dBc.
Shock pulses from a bearing normally occur at irregular interval, while strong, rhythmic shocks are a
sign of disturbance. The diagrams below show typical patterns.
B
A. Good bearing
Shock values are low.
C
E
F
D
B. Bad bearing
High values, large delta,
irregular pattern.
C. Pump cavitation
Very small delta, fairly high
shock level.
F. Measured value drops sharply
A danger signal, the bearing is sliding.
E. Regular showers
Scraping machine parts.
D. Load shocks, valves, etc.
Regular patterns mean often
disturbance
A
Содержание leonova emerald
Страница 1: ...User guide PORTABLE EFFICIENCY ...
Страница 2: ......
Страница 6: ...A 2 General instrument functions A ...
Страница 36: ...B 2 General measurement functions B ...
Страница 74: ...C 2 Measurement techniques always included B C ...
Страница 88: ...D D 2 Shock pulse measurement ...
Страница 122: ...D D 36 Shock pulse measurement ...
Страница 124: ...E E 2 Vibration measurement ...
Страница 150: ...E E 28 Vibration measurement ...
Страница 152: ...F F 2 Rotor balancing ...
Страница 170: ...F F 20 Rotor balancing ...