ANALOG OUTPUT CALIBRATION
Although the analog output has been calibrated at the factory, zero and span
adjustments are provided to compensate for small offsets and drifts. If excessive
drift is noticed, the following calibration procedure may be performed.
Scale the analog output by entering an arbitrarily larger display value for
“AN-HI”
then for “AN-LO”, in
“PRO 8”.
Note: Set the analog output source assignment for input.
4 to 20 mA Calibration
Exit the programming mode and apply a
(temperature)/(resistance)
to the
input of the indicator so that the display reading is below that of the value entered
for
“AN-LO”
. Adjust the zero potentiometer
(right side)
so that exactly 4.00 mA
flows, as verified by an accurate ammeter. Next, apply a
(temperature)/
(resistance)
to the indicator so that the display reading is above that of the value
entered for
“AN-HI”
. (See Appendix “B” for max. input voltage.) Adjust the
span potentiometer
(left side)
so that 20.00 mA is flowing. Repeat the zero and
span adjustments until both are accurate. Analog output calibration is complete.
0 to 10 VDC Calibration
Exit the programming mode and apply a
(temperature)/(resistance)
to the
input of the indicator so that the display reading is below that of the value entered
for
“AN-LO”
. Adjust the zero potentiometer
(right side)
so that exactly 0.00 VDC
flows, as verified by an accurate voltmeter. Next, apply a
(temperature)/
(resistance)
to the input of the indicator so that the display reading is above that of
the value entered for
“AN-HI”
. (See Appendix “B” for max. input voltage.) Adjust
the span potentiometer
(left side)
so that 10.00 VDC is flowing. Repeat the zero
and span adjustments until both are accurate. Analog output calibration is
complete.
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