Analog Inputs - GE DigitalFlo XGM868i Service Manual

B.4.2 Analog Inputs
Analog inputs may be added to the Model XGM868i by installing an appropriate option card in
contains two or four analog inputs, which are designated as A, B, C and D. Both the zero-point and full-scale values for
each input must be calibrated.
Calibration of the analog inputs requires the use of a calibrated current source. If an independent calibrated current
source is not available, one of the
calibration, the analog output will supply the low reference, high reference, 4 mA and 20 mA signals at the
Slot 0
appropriate times.
If a analog output will be used to calibrate the analog inputs, the
IMPORTANT: Slot 0
procedure must be completed first.
Prepare for the calibration procedure by connecting a
of the option card. See Figure 4 on page 12 to identify the
Input A
Note: The zero point of the analog input may be set for either 0 mA or 4 mA. However, the calibration procedure
always uses the 4 mA point, as the meter will extrapolate this value to obtain the 0 mA point.
1. In the center pane of the Calibration/Test window, double-click on Slot 1.
2. Double-click on the desired input to open the Analog Input menu. (
manual.)
Calibrating
IMPORTANT:
source on terminal block
3. Double-click on the appropriate option to select the reference point to be calibrated.
Proceed to the corresponding sub-section for specific instructions on each of the options available in step 3.
B.4.2a 4 mA Option
Set the calibrated current source to 4 mA.
•
If you selected the 4 mA option in the Analog Input menu, double-click on Store to accept the current 4 mA value or
on Abort to cancel the entry. In either case, the Analog Input prompt reappears.
B.4.2b 20 mA Option
Set the calibrated current source to 20 mA.
•
If you selected the 20 mA option in the Analog Input menu, double-click on Store to accept the current 20 mA value
or on Abort to cancel the entry. In either case, the Analog Input prompt reappears.
Click [Exit Page] to return to the Slot 1 window and calibrate additional inputs/outputs, or click [Exit Page] again to
close the Calibration/Test menu.
DigitalFlow™ XGM868i Service Manual
analog outputs may be used for the calibration. During the analog input
Slot 0
is identical to calibrating
Inputs B, C or D
. Refer to Figure 4 on page 12 for the correct pin numbers.
J2
Appendix B. Calibration and Testing with PanaView
analog output (or independent calibrated current source) to
Slot 0
and
IN(+) RTN(-)
Input A
. However, be sure to reconnect the current
Input A
Slot 1 . This option card
analog output calibration
Slot 0
pins for on terminal block J2.
Input A
will be used as an example in this
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