SPM T30 - Measuring Points and Transducers for VIB

Technical data are subject to change without notice.
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Measuring points and transducers for VIB
Vibration severity is defined as the RMS (root mean square) value of vibration velocity measured in
the frequency range of 3 to 1000 Hz. It is the best indicator for the energy contents of machine
vibration.
Vibration velocity is primarily a measure for general machine condition. Vibration at the measuring
point should be representative for the overall vibration of the machine. Typical measuring points
are bearing housings. By measuring in three directions, you can get an indication of the causes for
increased vibration:
VIB H: Horizontal in the plane of rotation, most representative for balance condition.
VIB V: Vertical in the plane of rotation, most representative for structural weakness.
VIB A: Axial along the line of the shaft, most representative for faulty alignment and bent
shafts.
The transducer TRV-22 (12) can be used
• as a hand-held probe, with or without the probe tip attached
• with a magnet for attachment to ferrous metal parts
• with the M8 mounting screw.
The transducer TRV-23 (13) can be used
• with the UNF 1/4” mounting screw.
The firmer the contact with the machine, the better the measuring result.
Vibration measuring points Attaching the transducer
Magnetic base Probe
Screw mounting
Measuring vibration 45