Omron CJ1W-AD041-V1, Operation Manual

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Analog Input Functions and Operating Procedures Section 7-6
In the following example, the peak value hold function is in effect for input
number 1, and the unit number is 0.
When mean value processing is used together with the peak value hold func-
tion, the mean value will be held.
As long as the peak value hold function is in effect, the peak value hold will be
held even in the event of a disconnection.
When the load to the CPU Unit is disconnected, the Peak Value Hold Bits (bits
04 to 07 of the word n) are cleared and the peak value hold function is dis-
abled.
7-6-5 Input Scaling Function
When upper and lower limits (within a decimal range of
−
32,000 to 32,000)
have been preset in 16-bit binary data (from 8300 to 7D00) in the CPU Unit’s
DM Area, analog input values can then be automatically converted into a
user-specified unit following A/D conversion, with the upper and lower limits
taken as full scale based on that resolution value. (See note 1.) This scaling
function eliminates the previous need to provide programs for numeric conver-
sion into specified units. It is only enabled, however, for a conversion time of 1
ms and a resolution of 4,000 (and not for a conversion time of 500
µ
s and a
resolution of 8,000).
Note 1. To set the upper or lower limit to a negative number, use two’s complement.
(Set 8300 to FFF for
−
32,000 to
−
1.)
2. Addresses m = unit number × 100 are allocated in the DM Area.
3. Besides upper limit > lower limit, it is also possible to set lower limit < upper
limit. (Reverse scaling is supported.)
4. Actual A/D conversion is executed at up to
−
5% to +105% of full scale.
5. When setting upper and lower limits in the DM Area in the specified units,
be sure to make the settings in 16-bit binary data (with negative values set
as two’s complement). For decimal numbers
−
32,000 to +32,000, set 16-
bit binary data (8300 to 7D00).
6. The scaling function is enabled for only a conversion time of 1 ms and a
resolution of 4,000 (and not for a conversion time of 500
µ
s and a resolu-
tion of 8,000).
7. The scaling function cannot be used when the ratio conversion function is
used.
8. If the scaling upper limit equals the lower limit, or if the scaling upper limit
or lower limit is outside the range of
±
32,000, a scaling data setting error is
generated and scaling cannot be executed. Operation starts normally
when both the upper and lower limits are set to 0000 (the default values).
Setting Upper and Lower
Limits for Input Scaling Set the scaling upper and lower limits for inputs 1 to 4 in words m+27 to m+34
of the DM Area, as shown below.
200004
Input condition
The maximum
conversion
data value is
held for input
number 1.