. i
6.0 sex 102 CALIBRATION
The calibration can be performed in two methods. Section 6. 1
describes the procedure when high precision input source, 5
digit DVM and a 250 ohm± 0.01% shunt is available.
Section 6.2 describes an alternate method of differential
measurement which is a bench test method and provides very
high accuracy calibration. In this case the input and output are
connected to provide differential error that must be nulled out.
This procedure does not need high precision source or shunt.
6.1 CALIBRATION WITH PRECISIONS COMPONENTS
To perform a calibration check or recalibration of the instrument,
follow the procedure below.
A. Make sure the input output wiring is connected properly
per diagram on front page.
B. The input signal source must be adjustable from
0-100% in steps of at least 25%. The source must be
either precalibrated or a precision milliammeter should
be used to monitor the input.
C. Monitor the output across a 250n ±.01 % shunt
D. Set the input source to 4.000 mA and adjust the multi
turn control marked ZERO to provide 4.000 ± mA
(1.000 vdc) within desired accuracy.
E. Set the input source to 20.000 ma and adjust the multi
turn potentiometer control marked SPAN to provide
20.000 mA (5.000 vdc across 250 ohm).
F. Repeat steps D and E until desired accuracy is achieved.
G. Check linearity at input of 8.000, 12.000 and 16.000 mA.
H. This completes the calibration.
CAUBRATJON CONNECTION
WITH PRECISION COMPONENTS
VOLTAGE
METER
6.2 CALIBRATION WITHOUT
PRECISION COMPONENTS
This method
cannot
be used when the isolator is connected in
the actual circuits, because it needs connecting the input to the
output which violates the 1/0 isolation.
A. Remove the input/output wiring and connect the
instrument per figure on right below.
B. Set the input source to approximately 4 made and
adjust the multi-turn potentiometer marked ZERO to
provide 0.000 volt reading on the null meter.
C. Set the input source to approximately 20 made and
adjust multi-turn potentiometer marked SPAN to provide
0.000 vdc on the null meter.
D. Repeat steps B and C until both readings provide 0.000
vdc on the null meter.
E. Check at inputs of 8, 12 and 16 ma for error if any.
7.0 TROUBLESHOOTING
AD TECH does not recommend field trouble shooting of these
device. Make sure the input and output connections are
correctly made and recheck operation. Return a defective
instrument to ADTECH factory for prompt check and
recalibration.
..
4.tt. OM111
(1S)
VOLTAGE
METER
Note 1 : Current source need not be a precision source
Note 2: Voltage at Meter=%Error(of 20mA) directly
CALIBRATION CONNECTIONS
WITH OUT PRECISION COMPONENTS
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190-A-SCX102-A