Omron CQM1H - 08-2005, Operation Manual

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word that stores the result. DM 0000 to DM 0011 are secured in the example
program.
* “n” indicates the allocated word for analog input.
Input condition
ANDW(34)
#0FFF
n
DM 0200
XORW(36)
#0800
DM 0200
DM 0200
AVG( )
DM 0200
#0300
DM 0000
3-3-2 Adjustment
The accuracy of the Analog Input Unit is
±
1% without adjustment. If this is ade-
quate, the user need not adjust the Analog Input Unit. Fine tuning of the Analog
Input Unit is explained in this section.
The Analog Input Unit is adjusted with parameters set with the SCL instruction.
If the Analog Input Unit is set to a range of 0 to 10 V, 1 to 5 V or 4 to 20 mA, follow
the steps described below to adjust the Analog Input Unit.
1, 2, 3... 1. Refer to 3-1 Settings and connect the Analog Input Unit, CPU, and sensor or
transducer.
2. Connect a peripheral device such as a Programming Console to the CPU (in
any mode) and monitor the allocated word of the analog input to be ad-
justed.
PS CPU OUT AD OUT
IN
AD IPS
Sensor or transducer Sensing object
Peripheral device
3. Obtain the minimum value of the sensing object. For a sensing operation, for
example, set the sensing object so that the output value of the sensor or
transducer will be minimum. For temperature measurement, it may be diffi-
cult to obtain the minimum value. In that case, instead of using the sensor or
transducer, use a reference power supply to obtain the output at the lowest
temperature.
4. Use the peripheral device to monitor the word to which the analog input data
to be adjusted is stored. The CQM1H/CQM1 can be in any mode. The ana-
log input conversion data will be the lower-limit value.
5. Apply the same method to the analog input’s maximum value to obtain the
upper-limit value.
0 to 10 V, 1 to 5 V,
or 4 to 20 mA
Programming and Adjustment
Section 3-3