Omron CJ1W-AD041-V1, Operation Manual

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Adjusting Offset and Gain Section 6-9
6-9 Adjusting Offset and Gain
These functions can be used to calibrate inputs or outputs according to the
devices that are connected.
Input Calibration Function This function takes an output device’s offset voltage (or current) and gain volt-
age (or current) as the analog input conversion data 0000 and 0FA0 (or 07D0
when the range is
±
10 V). For example, when used in a range of 1 to 5 V, a
range of 0.8 to 4.8 V may be output even if the external device specifications
are for 1 to 5 V. In such cases, when the external device outputs an offset volt-
age of 0.8 V, the converted data at the Analog Input Unit will be FF38. When a
gain voltage of 4.8 V is output, the converted data will be 0EDA. With the off-
set and gain adjustment functions, when 0.8 V and 4.8 V are input, then the
values are converted to 0000 and 0FA0 respectively (instead of FF38 and
0EDA).
Input Calibration Function This function adjusts output voltages according to input device offset values
and gain values, and takes the presently set values of the Unit to be 0000 and
00FA0 (or 07D0 when the range is
±
10 V) respectively. For example, assume
that the specifications for an external input device (such as a display device)
are 100.0 to 500.0. If voltage is output by the Analog Output Unit at a set
value of 0000, and the actual display at the external input device shows not
100.0 but 100.5, the output voltage can be adjusted (lowered in this case) so
that the display will show 100.0, and the set value (FFFB in this case) when
the display shows exactly 100.0 can be set as 0000.
Similarly, for the gain value, if the Analog Output Unit outputs voltage at a set
value of 0FA0, and the actual display at the external input device shows not
500.0 but 500.5, the output voltage can be adjusted (lowered in this case) so
that the display will show 500.0, and the set value (0F9B in this case) when
the display shows exactly 500.0 can be set as 0FA0.
Output device
offset and gain
voltage
Converted data before
adjustment
Converted data after
adjustment
0.8 V FF38 0000
4.8 V 0EDA 0FA0
Display at external
input device
Set value before adjustment
(word n+8)
Set value after adjustment
100.0 FFFB 0000
500.0 0F9B 0FA0