Protection
Protection Module Configuration with IMx-M Manager
2 - 108
SKF Multilog O
n-Line System IMx-M
User Manual
•
Filter:
Filter roll off factor is 24 dB/Octave (4
th
order) for both High Pass
Filter and Low Pass Filter.
The deviation in the pass band is within
±
0,5 dB.
Configuring a filter appropriately is very important:
–
To limit the influence of noise, choose a filter that is as tight as
possible around the frequency band of interest.
–
If possible, It is recommended to use RMS rather than PtP in the
application.
Available Filter Ranges:
–
DC
: 0 to 0,625 Hz filter for temperature and process data such as
pressure or flow.
–
0 to 10 Hz
: narrow range for Eccentricity.
–
10 to 1 000 Hz:
mostly for velocity (according to API 670).
–
1 to 600 Hz:
–
4 to 4 000 Hz:
–
5 to 1 000 Hz:
for equipment with shaft speed of 300 to 750 rpm.
–
10 to 5 000 Hz
: for a specified acceleration.
–
1 000 to 10 000 Hz:
mostly for acceleration.
–
User defined
: allows user to manually set the filter ranges.
Limitations on Low Pass Filter Usage:
–
For low pass filter > 1 000, no Integration allowed.
–
For low pass filter > 2 400, no combined measurements allowed.
–
For low pass filter > 4 800, only one channel in the pair may be used.
Limitations on High Pass Filter Usage:
–
For high pass filter < 5 Hz, no integration allowed and measurement
time will increase.
Limitations on User Defined Filter Usage:
–
High pass filter >= 1 Hz
–
150 Hz <= low pass filter <= 5 000 Hz. Additionally low pass filter can
also be set to 10 000 Hz.
–
Low pass filter > 5,7 * high pass filter. However, filter band of 30
−
150
Hz and 100
−
300 Hz are allowed.
–
The limitations on both low and high pass filter usages stated above
are also applied to the limitations on the user defined filter usage.