Omicron CMC 430, Руководство пользователя

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3.10.3.2 Potential free mode
In the potential free binary input mode, a small voltage is applied to the input for sensing the state of a
connected dry contact. The threshold and range are programmed automatically.
Characteristic Specification
Trigger criteria Logical 0: R > 80 kΩ
Logical 1: R < 20 kΩ
Typical input impedance 106 kΩ || 170 pF
+
+
+
170 pF
1 MΩ
V
threshold
119 kΩ
19 V
3.10.3.3 AC sensing mode
In this mode, the sample data are digitally rectified and then compared to the threshold. This process
converts the AC input voltage to a pulsing DC voltage. The deglitch time has to be set appropriately
depending on the threshold in order to avoid that the
CMC 430 triggers on every half wave of the
signal. The following settings are recommended and should work sensibly for sinusoidal 50 Hz and
60 Hz signals:
• Threshold set to one third of the nominal voltage
• Deglitch time set to 3 ms
t
t
t
V
threshold
T
deglitch
T
deglitch
Technical data
OMICRON 35