USER MANUAL
Document reference MAODS301/E
SpeedSys300 ODS301 overspeed detection system
Edition 4 - May 2022
5 - 6
Measurement tab
COMMISSIONING OF A SPEEDSYS300 ODS301
•
Acceleration calc. averaging
Number of pulses to be used for the calculation of the moving average of the frequency,
which is strictly used for acceleration calculation.
•
Acceleration lookup depth
The acceleration value is evaluated from two frequency values and their timestamps. For
evaluation, the last frequency and one of the previous is considered. Which of the previous
values is to be considered is determined by the user in the measurement configuration
parameters as the “acceleration lookup depth”. This parameter can be set between 1 and
5000.
The acceleration is calculated by dividing a frequency difference by the time that has passed.
The difference is calculated from averaged frequencies (see the image below). The time
between the two frequency averaging periods is defined by the depth-parameter (as it is
given as a number of pulses, the actual time is frequency dependent).
•
Acceleration lookup factor
The lookup factor can be used for a dynamic lookup depth. If the lookup factor is used, the
lookup depth is calculated by the ratio of the measured frequency and the specified lookup
factor, as described in the following formula:
D
f
= f
n
/ x
lookup
Where
D
f
: Lookup depth calculated from depth factor. Lower limit is 1, upper limit is the fixed
acceleration lookup depth parameter.
f
n
: Frequency evaluated for pulse n.
x
lookup
: Acceleration lookup factor. If the parameter is set to 0, the fixed acceleration lookup
depth parameter is applied.
Summary of Contents for vibro-meter SpeedSys300 ODS301
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