Panametrics DigitalFlow XMT868i, Руководство по обслуживанию

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Appendix B. Calibration and Testing with PanaView
24 DigitalFlow™ XMT868i Service Manual
B.4.2 Analog Inputs
Analog inputs may be added to the Model XMT868i by installing an appropriate option card in Slot 1. This option card
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 Slot 0 analog outputs may be used for the calibration. During the analog input
calibration, the Slot 0 analog output will supply the low reference, high reference, 4 mA and 20 mA signals at the
appropriate times.
IMPORTANT: If a Slot 0 analog output will be used to calibrate the analog inputs, the Slot 0 analog output
calibration procedure must be completed first.
Prepare for calibration procedure by connecting a Slot 0 analog output (or an independent calibrated current
source) to Input A of the option card. See Figure 4 on page 12 to identify the IN(+) and RTN(-) pins for Input A on
terminal block J2.
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 input to be calibrated.
IMPORTANT: All inputs are calibrated in an identical manner. However, be sure to reconnect the current source on
terminal block J2 . See Figure 4 on page 12 for the correct pin numbers.
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.0.0a 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.0.0b 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.