SPM leonova emerald, User Manual

Page: 140 / 170

E
E:18
Vibration measurement
Trigger selection
The trigger function (2) can be set ‘Post trigger’
or ‘RPM trigger’. ‘Post trigger’ is primarily used for
measuring in rolling mills.
- ‘Trigger Level’ (3) is set to activate measurement
when the vibration/rpm level exceeds/falls below
the set value.
- “Delay time” (4) is a delay in seconds before the
measurement begins after the ‘Trigger level‘ is
exceeded.
- ‘‘RPM trigger type” (5) can be set to ‘RPM run up’
or ‘RPM run down’ (6). The measurement begins
when the rpm exceeds respectively falls below
the set trigger level.
2
3
5
4
6
Zoom centre and zoom factor
True zoom (1) is selected to get a high resolu -
tion around a selected ‘centre frequency’. This
frequency must be within the selected frequency
range. Thus, to zoom in on 600 Hz, the minimum
range is 0 to 1000 Hz. The zoom factor can be set
to 2, 4, 8, 16, 32 or 64. The range covered by the
zoom is ‘upper frequency range/zoom factor’. Thus,
with a zoom factor of 8, the spectrum will cover the
range 537.5 - 662.5 Hz.
The highest possible zoom corresponds to a 12800
line spectrum. For this, combine the lowest number
of spectrum lines, 400, with a zoom factor of 32
(32 x 400 = 12800). With a centre frequency of 600
Hz, you will get a spectrum over the range 584.375
to 615.625 Hz, with a resolution of 0.078125 Hz.
When using the optional function ‘Order tracking’
the zoom centre frequency is set in orders.
1