SPM leonova emerald, User Manual

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D
D:24
Shock pulse measurement
The LR/HR technique was originally developed for a continuous, automatic monitoring system (CMS).
An automatic system cannot, like a human operator, vary measuring time, use earphones or make
”further tests” to verify suspect readings. It works with fixed settings and is dependent on accurate
input data. This, together with new research results, programmable chips, and the desire to get more
detailed information from the shock pulse signal, lead to a change in the threshold values, plus a more
diverse and detailed output.
The value for the noise carpet (HR) is read at an occurrence rate of approx. 1000 pulses/second and the
value for the strong shock pulses (LR) at approx. 40 pulses/second. This makes LR an average value of
the strong pulses, lower than the maximum, and thus reduces the dynamic range. To increase accuracy,
the mean diameter of the bearing is used, the SPM TYPE no. is input to define bearing geometry, and
the COMP no. to calibrate the individual measuring points.
The extra output information concerns mainly lubrication condition, allowing the user to attack a
mayor maintenance problem (most bearings fail too soon because of inadequate lubrication) at the
root. With SPM’s LUBMASTER
®
(part of Condmaster
®
versions for this technique) and LR/HR readings,
it is possible to accurately measure lubrication condition, calculate the resulting L
10a
life, and work out
feasible improvements by simulating changes in the lubricant parameters.
The basic principles for LR/HR and LR/HR HD are the same; however LR/HR HD utilizes the SPM HD
algorithms for time signals and spectrums. Both methods are most advantageous for RPMs above 500.
The LR/HR and SPM LR/HR HD techniques
Mean diameter Dm
TYPE
RPM
COMP
TYPE 3 TYPE 1
LR
HR