325
Analog Output Terminals
Section 5-8
4 to 20 mA
Values 0000 to 1770 Hex (0 to 6000) correspond to currents between 4 and
20 mA. The output range is 3.2 to 20.8 mA.
Switching between 2 and 1
Outputs
It is possible to restrict the number of outputs with pin 2 of DIP switch SW101.
In accordance with the number of outputs, the number of words allocated to
the Analog Output Terminal in the PLC for the Master Unit will also be set to 2
words/2 points or 1 word/1 point. When the number of outputs is 2, Outputs 0
and 1 will be used; and when the number of outputs is 1, Output 0 will be
used.
Output Data During
Communications Error
Pins 7 and 8 of DIP switch SW102 are used to select one of the following
methods for processing output data when a communications error occurs in
the CompoBus/S System.
Pin 7 OFF, Pin 8 OFF: Clear to lower limit value
Pin 7 OFF, Pin 8 ON: Clear to upper limit value
Pin 7 ON, Pin 8 OFF: Clear to 0 V (when voltage range is
–
10 to 10 V.)
Clear to lower limit value (All other times.)
Pin 7 ON, Pin 8 ON: Hold the value immediately preceding error
When the pins are set at Low Clear, High Clear, or 0 V, output data will
become as shown in the following table.
DA Conversion Data
In the Master Unit, DA conversion data should be output as shown in the fol-
lowing diagram.
To output a negative voltage is output, specify DA conversion data as 2
’
s com-
plement. The NEG instruction can be used to obtain the 2
’
s complement from
the absolute value.
Current
Hexadecimal
(decimal)
conversion data
FED4
(–300)
189C
(6300)
1770
(6000)
0000 (0)
4 mA
0 mA
3.2 mA
20.8 mA
20 mA
8000
7FFF
Output range
Pin 7 OFF,
Pin 8 OFF
Pin 7 OFF,
Pin 8 ON
Pin 7 ON,
Pin 8 OFF
0 to 5 V
–0.25 V
5.25 V
–0.25 V
1 to 5 V
0.8 V
5.2 V
0.8 V
0 to 10 V
–0.5 V
10.5 V
–0.5 V
–10 to 10 V
–11 V
11 V
0 V
4 to 20 mA
3.2 mA
20.8 mA
3.2 mA
Bit
First word
Output 0 DA conversion data
First word + 1
Output 1 DA conversion data
3
0
2
1
4
6
5
7
8
10
9
11
12
14 13
15
