Omron CRT1 - 10-2009, Operation Manual

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Analog I/O Slave Units
Section 6-1
6-1 Analog I/O Slave Units
6-1-1 Analog I/O Slave Units
In the Analog I/O Slave Unit, various functions such as a scaling function and
a peak/bottom hold function can be used in addition to AD/DA conversion of
the analog I/O data.
Furthermore, various types of calculations for analog input values that previ-
ously had to be processed using a high level PLC ladder program can be pro-
cessed in the Analog Input Slave Unit.
In addition, the data calculated using these functions can be selected as "ana-
log data", combined with status information such as "Analog Status Flag", and
allocated to I/O.
Allocating and monitoring of this status information, setting up Analog Unit
specific functions, and data monitoring can easily be performed using CX-
Integrator.
6-1-2 List of Data Processing Functions
The following tables list the data processing functions that can be used with
Analog I/O Slave Units. Refer to
11-4 Analog I/O Slave Unit (input) Functions
and 11-5 Analog I/O Slave Unit (output) Functions for details on functions and
setting methods.
Analog Input Slave Unit
Function Details Default
Setting of number of
AD conversion
points Reducing the number of input conversion points
increases the speed of the conversion cycle. 4
Moving average
function Averages the most recent 8 values of the analog
input value.
This provides a smooth input value for an input that
oscillates.
Disabled
Scaling Performs scaling.
The analog input value can be converted into
industrial units that can be utilized by the user,
reducing the calculation load on the ladder pro-
gram of the master PLC. Scaling also supports an
offset function for compensating for mounting
errors in sensors and other devices.
Disabled
0 to 6,000
Peak/bottom hold Holds the maximum value and minimum value of
the analog input value. Disabled
Top/valley hold This holds the "tops of the mountains" and "bot-
toms of the valleys" of the analog input values. Disabled
Rate of change This calculates the rate of change of the analog
input values for each set sampling cycle. Disabled
Comparator Analog input values or data after calculation (peak
value, bottom value, top value, valley value, rate of
change) are compared to 4 types of set values:
Alarm Trip Point High (HH), Warning Trip Point
High (H), Warning Trip Point Low (L), and Alarm
Trip Point Low (LL) and the results are notified
using the Analog Status Flag. Disabled
Disconnected line
detection Detects disconnections of analog inputs. (Valid
only for the input ranges 4 to 20 mA and 1 to 5 V) Enabled
User adjustment "Shift" generated from measurement error due to
hardware can be adjusted to an arbitrary input
value. Disabled