Meggitt vibro-meter VM600 - Page 171

Document reference MAMPS-HW/E HARDWARE MANUAL
Edition 18 - March 2022 VM600 machinery protection system (MPS)
7-9
Shaft absolute vibration
PROCESSING MODES AND APPLICATIONS
(2) Block diagram
As shown in Figure 7-6, shaft absolute vibration is a dual-channel processing function where
absolute shaft displacement (output from BBAB processing) is added to relative shaft
displacement (output from RS processing).
NOTE: The MPC4 card performs shaft absolute vibration processing synchronously in
real-time, using the raw waveform signals from the two processing functions
(BBAB and RS) with digital integration only (not analogue integration).
Channel 1
vib. input
Figure 7-6: Block diagram showing absolute shaft vibration processing
Output 1
AB vib. value
Available rectifiers:
RMS
Mean
Peak
Peak-Peak.
AC
DC
Initial
gap
Channel 2
vib. input
(Broad-band absolute bearing vibration (BBAB)
Output 1
AB vib. alarm
Output 2
AB vib. alarm
Output 2
AB vib. value
Dual Output
AS vib. alarm
Dual Output
AS vib. value
Output 1
RS vib. value
Output 1
RS vib. alarm
Output 2
gap value
Output 2
gap alarm
(Relative shaft vibration (RS))
Absolute shaft
vibration (AS)