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Analog Output Units Section 7-3
Allocation of Output
Words
Four output words are allocated, beginning from the first word following the
last I/O word allocated to the CPU Unit or already-connected Expansion I/O
Unit or Expansion Unit.
Writing the Range Code Write the output use and the range code to words n+1 and n+2. The D/A con-
version will start when the set data is transferred from the CPU Unit to the
Analog Output Unit.
â– Range Code
• The Analog Output Unit will not start converting analog I/O values until the
range code has been written. The output will be 0 V or 0 mA.
• From when the range code has been written until data in the analog out-
put convertible range is written, 0 V or 0 mA will be output in the 0 to 10 V,
-10 to +10 V, and 0 to 20 mA ranges, and 1 V or 4 mA will be output in the
1 to 5 V and 4 to 20 mA ranges.
• Once the range code has been set, it is not possible to change the setting
while power is being supplied to the CPU Unit. To change the I/O range,
turn the CPU Unit OFF then ON again.
3. Ladder Program
Words n+1 to n+4
Analog Output Unit
15 0
1 0 0 0 0 0 0
87654321
Wd n+1
15 0
1 0 0 0 0 0 0
87654321
0
0
Analog output 2 Analog output 1
Analog output 4
Analog output 3
Set to 1.
Set to 1.
Wd n+2
0
1
Range code
Analog output signal range
−10 to 10 V
0 to 10 V
1 to 5 V
0 to 20 mA
4 to 25 mA
000
001
010
011
100
Output use
No
Yes