Showa DS-6200, Руководство по эксплуатации

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5 SETTING OF FUNCTIONS
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Caution regarding inflection point hold
If the detection Inflection front sope time and Inflection
rear sope time are set too short, fine load changes may be
detected as shown in the illustration on the left-hand side,
so that a correct value cannot be held.
In this case, set the detection inflection rear sope time
large enough to bring it as close to the load change time as
possible, and also set the inflection minimum slope large
according to the amount of change at that time, so that the
inflection point is held at a correct position.
Example of inflection point hold setting
● Example of ideal waveform setting
① Set the load change time (between the inflection point and when the change stops) to
inflection rear sope time. In the example, it is set to 200 since it is 100 msec.
② Set the same value as inflection rear sope time to inflection front sope time.
③ Set load D obtained by subtracting load C changing with inflection front sope time from the
load changing with inflection rear sope time to the inflection minimum slope.
In the example, set load change D=80 obtained by subtracting load C=10 changing with A
from load 90 changing with B to the inflection minimum slope.
However, since an inflection point is not judged until load change D exceeds the inflection
minimum slope, actually set the inflection minimum slope a slightly smaller than D.
● If the inflection point cannot be located successfully
① When holding above the inflection point and moving downward
1) It is considered that the inflection minimum slope is small with
respect to load change D. Set the inflection minimum slope
larger.
2) If lowering is insufficient in 1), increase inflection front sope
time.
② When holding below the inflection point and moving upward
inflection rear sope time is too long and the inflection minimum
slope is too large.Shorten inflection rear sope time and decrease
the inflection minimum slope.
Inflection front (rear) slope time setting is the number of samplings. Since the DS-6200's
sampling speed is 2000 times/sec., one sampling is 0.5msec.
Therefore, setting of the interval at 100 means setting of 50msec.
Load change time
True inflection
Inflection
point
point
100
20
10
0
100msec
A
100msec
B
D = 80
C = 10
①
②