Omron CRT1 - 10-2009, Operation Manual

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Summary of the Analog Input Slave Units
Section 6-2
6-2 Summary of the Analog Input Slave Units
Analog Input Slave Units convert (AD conversion) analog input signals such
as 1 to 5 V and 4 to 20 mA to digital data (binary values) and stores them in
the Master Unit.
A summary of the Analog Input Slave Unit is described below.
6-2-1 Input Range and Conversion Data
Input analog signals are converted to digital data in the following manner
using a set input range.
If the input data exceeds the data range for which conversion is possible, the
conversion data saturates at the upper or low limit.
Input Range and
Conversion Data
■
Input Range: 0 to 5 V
Voltage of 0 to 5V is converted to data from 0000 to 1770 Hex (0 to 6000). The
input data range for which conversion is possible is
–
0.25 to +5.25 V and here
the output data is FED4 to 189C Hex (
–
300 to +6300). When input data is a
negative voltage, it is expressed as the two's complement (hexadecimal) and
the output data for a disconnected line is the same as for an input of 0 V (0000
Hex).
■
Input Range:1 to 5 V
Voltage of 1 to 5V is converted to data from 0000 to 1770 Hex (0 to 6000). The
input data range for which conversion is possible is 0.8 to 5.2 V and here the
output data is FED4 to 189C Hex (
–
300 to +6300). If the input value falls
below the input range such as for a disconnected line (input voltage is less
than 0.76 V), a disconnected line detection function activates and data is set
to 7FFF Hex.
189C (6300)
1770 (6000)
0000 (0)
0 V
FED4 (
−
300)
−
0.25 V
5 V 5.25 V
Conversion data
Hexadecimal (decimal)
Voltage