First-order lag filter, First-order lag filter -32 – Yokogawa Standalone MW100 User Manual
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IM MW100-01E
30-CH Medium Speed DCV/TC/DI Input Module
Measurement
Interval
Integration
Time
Rejected Frequencies and Notes
500 ms
1.67 ms
600 Hz and its integer multiples*
1, 2 s
16.67 ms
60 Hz and its integer multiples
20 ms
50 Hz and its integer multiples
Auto
Automatically detects the power supply frequency and set 16.67 or 20 ms
5 s
36.67 ms
50 Hz and 60 Hz and their integer multiples
10, 20, 30, 60 s
100ms
10 Hz and its integer multiples
* Because the power supply frequency noise is not rejected, measured values may fluctuate particularly for
temperature measurements using thermocouples. If this happens, make the measurement interval longer, or use
the 4-CH High-Speed Universal Input Module or the 10-CH Medium-Speed Universal Input Module
Measurement
Interval
100 ms
1.67 ms
16.67 ms
20 ms
Auto
Integration
Time
Rejected Frequencies and Notes
200 ms
500 ms
1 s
2 s
5, 10, 20, 30, 60 s
36.67 ms
100 ms
200 ms
600 Hz and its integer multiples*
60 Hz and its integer multiples
50 Hz and its integer multiples
Automatically detects the power supply frequency and set 16.6 or 20 ms
50 Hz and 60 Hz and their integer multiples
10 Hz and its integer multiples
Low-pass filter with Fc = 5 Hz
4-CH, Medium-Speed Strain Input Module
* When the measurement interval is 100 ms, measured values may fluctuate since power supply frequency
noise is not rejected.
In such cases, set the measurement interval to 200 ms or more.
First-Order Lag Filter
For noise sources other than power supply noise, the MW100 Data Acquisition Unit is
equipped with a first-order lag filter having output characteristics indicated in the figure
below against step input.
For the filter setting, the time constant is determined by selecting filter coefficient N for
the measurement interval.
Step input
63.2% of the output value
Time constant
0%
100%
Output characteristics
Filter coefficient = measurement interval x filter coefficient N
Measurement Interval (s)
Selectable Time Constants (s)
N=5
N=10
N=20
N=25
N=40
N=50
N=100
0.01
0.05
0.1
0.2
0.25
0.4
0.5
1
0.05
0.25
0.5
1
1.25
2
2.5
5
0.1
0.5
1
2
2.5
4
5
10
0.2
1
2
4
5
8
10
20
0.5
2.5
5
10
12.5
20
25
50
1
5
10
20
25
40
50
100
2
10
20
40
50
80
100
200
5
25
50
100
125
200
250
500
10
50
100
200
250
400
500
1000
20
100
200
400
500
800
1000
2000
30
150
300
600
750
1200
1500
3000
60
300
600
1200
1500
2400
3000
6000
2.9 Measures Against Noise on the MW100 Data Acquisition Unit