GE Bently Nevada 86517 Operation Manual page 29

Section 4 - MAINTENANCE
Isolation and Correction:
Because this type of problem is usually observed at the monitor, you need
to determine if the fault lies with the transducer system, the monitor, or, in
the case of 1X filtered monitor channels, with the rotor speed signal. Check
the components of the transducer system in the following order:
Check all connectors and connections in the signal path. Check the
accelerometer mounting. Check the extension cable for damage and
make sure it is well secured at regular intervals to prevent cable vibration.
Verify that the interface module is isolated from earth and that the shields
are wired correctly.
If the problem still exists after completing the troubleshooting procedure
and you are sure the spiking is not a real vibration signal then replace the
transducer system components one at a time until the problem is
resolved. Replace the extension cable first, then the interface module, and
replace the accelerometer last.
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