Reading Analog Input Converted Values; Writing Analog Output Converted Values - Omron CP1L-EL20DR-D Operation Manual

Analog I/O Units

Reading Analog Input Converted Values

The ladder program can be used to read the memory area words where the
converted values are stored. Values are output to the next two words (m + 1,
m + 2) following the last input word (m) allocated to the CPU Unit or previous
Expansion Unit or Expansion I/O Unit.

Writing Analog Output Converted Values

The ladder program can be used to write data to the memory area where the
set value is stored. The output word will be "n+1," where "n" is the last output
word allocated to the CPU Unit or previous Expansion Unit or Expansion I/O
Unit.
Startup Operation
After power is turned ON, it will require two cycle times plus approx. 50 ms
before the first data is converted. The following instructions can be placed at
the beginning of the program to delay reading converted data from analog
inputs until conversion is actually possible.
Analog input data will be 0000 until initial processing has been completed.
Analog output data will be 0 V or 0 mA until the range code has been written.
After the range code has been written, the analog output data will be 0 V or
0 mA if the range is 0 to 10 V, −10 to 10 V, or 0 to 20 mA, or it will be 1 V or
4 mA if the range is 1 to 5 V or 4 to 20 mA.
Always ON Flag
P_On
T0005
MOV(021)
Handling Unit Errors
• When an error occurs in the Analog I/O Unit, analog input data will be
0000 and 0 V or 0 mA will be output as the analog output.
If a CPU error or an I/O bus error (fatal errors) occurs at the CPU Unit and
the analog output is set to 1 to 5 V or 4 to 20 mA, 0 V or 0 mA will be out-
put. For any other fatal errors at the CPU Unit, 1 V or 4 mA will be output.
• CP-series Expansion Unit or Expansion I/O Unit errors are output to bits
0 to 5 of word A436. The bits are allocated from A436.00 in order starting
with the Unit nearest the CPU Unit. Use these flags in the program when
it is necessary to detect errors.
Program Example
This programming example uses these ranges:
Analog input 0: 0 to 10 V
Analog input 1: 4 to 20 mA
Analog output: 0 to 10 V
TIM
TIM 0005 will start as soon as power turns
0005
ON. After 0.2 s (200 ms), the input for TIM
0005 will turn ON, and the converted data
#0002
from analog input 0 that is stored in word 2
will be transferred to D0.
2
D0
Section 9-4
495