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Analog I/O Modules (AD268 / DA264 / TC218)
6. Parameters
PART 1 AD268
Gain calibration value & Offset calibration value:
(Gain: H8000 to H8007, Offset: H8008 to H800F)
At the factory shipment, the AD268 is calibrated for each input range. Therefore, there is no
need for user to calibrate normally.
However, depending on the usage condition, field adjustments are required. For this purpose,
the AD268 has the gain and offset calibration function.
In the AD268, the A/D conversion data is calculated as follows.
When the gain calibration value is G and the offset calibration value is O, the conversion
calculation is performed in the AD268 as follows.
X
2
= (X
1
+ O)
×
G / FS
X
1
:
Initial A/D conversion value
X
2
:
Gain/offset processed value
O:
Offset calibration value (buffer memory address H8008 to H800F)
G:
Gain calibration value (buffer memory address H8000 to H8007)
FS:
Full scale value
32000 for
±
10V and 0 to 10V ranges
16000 for
±
5V, 0 to 5V and 0 to 20mA ranges
12800 for 1 to 5V and 4 to 20mA ranges
The data setting range of the gain and offset calibration value are as follows.
Input type
Gain calibration value
Upper limit
32000
Default value
32000
±
10V
0 to 10V
Lower limit
10000
Upper limit
16000
Default value
16000
±
5V
0 to 5V
0 to 20mA
Lower limit
5000
Upper limit
12800
Default value
12800
1 to 5V
4 to 20mA
Lower limit
4000
Input type
Offset calibration value
Upper limit
3200
Default value
0
All types
Lower limit
-3200
Analog input
A/D
conversion
Offset
processing
Gain
processing
A/D conversion data
(read by T2 CPU)
CTi Automation - Phone: 800.894.0412 - Fax: 208.368.0415 - Web: www.ctiautomation.net - Email: [email protected]
