GE Bently Nevada 3300/25, Руководство по эксплуатации

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3300/25 Dual Accelerometer Input Monitor Operation Manual
72
19.11.2 Setting the Low-Pass Corner Frequency
1) Select a value for clock frequency (fCLK) from this list. We recommend that you
start with 3.58 MHZ.
2)
Calculate the divider ratio D using this equation. is The clock frequency, f
CLK
, (in Hz)
is selected in step 1 and f
LP
is the desired low pass corner frequency (in Hz).
LP
CLK
f × 40
f
= D
3) Choose the value for the divider ratio in this list that is closest to the value for D
that you calculated in step 2.
CONDITION ACTION
If the value for the divider ratio from the list
in step 3 is...
within ±1 of the value calculated in step 2
set the jumpers for the low pass
corner frequency by continuing with
steps 4 and 5.
not within ±1 of the value calculated in step
2
choose the next lower value for clock
frequency in the table from step 1
and repeat steps 2 and 3.
If you cannot find values for f
CLK
and D that
give the low pass frequency you need...
use the clock frequency and divider
ratio that gives a low-pass corner
frequency that is closest to the
corner frequency you need.
MHZ kHz
3.58
2
1
500
250
125
4
5
6
9
10
12
14
15 16
18
20
22
23
24
25
26 27
28
29
30
31
32
33
34 35
36
37
38
39
40
41
43 44
45
46
47
50
52
53
56 58
60
61
64
69
74
78
81 85
87
89
90
99
112
128
149 179
188
224
298
358
447
895
2048