Omron CJ1W-AD041-V1, Operation Manual

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Analog Output Functions and Operating Procedures Section 7-7
To specify the output hold function, use a Programming Device to set the DM
Area words D(m+2) to D(m+5) as shown in the following table.
For the DM word addresses, m = (unit number x 100).
Note After specifying the DM settings from a Programming Device, it will be neces-
sary to either turn the power to the PLC OFF and ON, or turn ON the Special
I/O Unit Restart Bit to transfer the contents of the DM settings to the Special I/
O Unit.
7-7-4 Output 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, within a range of
−
32,000 to 32,000 decimal, analog output set val-
ues are automatically converted to the resolution value with the upper and
lower limits taken as full scale, and are then converted from digital to analog.
(See note 1.) This scaling function eliminates the previous necessity of provid-
ing programs for numeric conversion from 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 x 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 D/A 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).
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).
DM word Function Set value
D(m+2) Output 1: Output status when stopped xx00: CLR
Output 0 or mini-
mum value of range
(–5%).
xx01: HOLD
Hold output value
prior to stop.
xx02: MAX
Output maximum
value of range
(105%).
Set any value in the leftmost
bytes (xx).
D(m+3) Output 2: Output status when stopped