Omron SYSMAC CJ1W-AD04U, Руководство по эксплуатации

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Supplementary Explanations of Functions Appendix B
Setting Process Value Scaling with Negative Gain
With process value scaling in industrial units, a negative gain can be set by reversing the maximum and
minimum values in the range.
The following values can be set for an input signal of 4 to 20 mA: Maximum process value in range = 0,
minimum process value in range = 4000.
Alarm Operation during Process Value Scaling with Negative
Gain
During process value scaling with negative gain, the alarm operates on the process value after scaling, and not
on the input signal. Consequently, the operation is the same as for normal bias, as shown below.
H Limit Alarms
When the input value is greater than the alarm set value, the alarm output is turned ON.
L Limit Alarms
When the input value is less than the alarm set value, the alarm output is turned ON.
Example: If the maximum process value in the range is 0 and minimum process value in the range is 4,000 for
an input signal of 4 to 20 mA, and if the H (high limit) alarm set value is 3,000, the alarm output will turn ON
when the process value is greater than 3,000 (when the input signal is less than 8 mA).
4200 (105%)
4000 (100%)
0 (0%)
−
200 (
−
5%)
3.2 mA 4 mA 20 mA 20.8 mA
Input signal
Process value (stored data)
Process value scaling with negative gain