Panametrics DigitalFlow GM868, Service Manual

Page: 17 / 72

DigitalFlow™ GM868 Service Manual 7
Chapter 1. Calibration
1.5 Calibrating the Analog Inputs (cont.)
For this discussion, assume that the option card has been installed in Slot x .
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.
1.5.1 Accessing the Calibration Menu
1. Press the [CAL] key to enter the
Calibration Program.
2. Press [Fx] to calibrate the desired slot . (The option bar will include a slot listing for each installed option card.)
3. Press [Fx] to select the desired input.
The procedure for calibrating Input A is identical to that for calibrating Input B . However, when calibrating Input B , be
sure a calibrated current source is connected to the appropriate pins on the terminal block. See Figure 3 on the
previous page for the correct pin numbers. To calibrate a 0/4-20 mA input card, see the section below.
Note: To calibrate an RTD input card, refer to page 9.
4. Press [F1]-[F4] to select the reference point to be calibrated.
Do one of the following:
• If you selected
[F1] (aLOW)
, proceed to
aLOW Option
on the next page.
• If you selected
[F2] (aHIGH)
, proceed to
aHIGH Option
on the next page.
• If you selected
[F3] (4 mA)
, proceed to
4 mA Option
on the next page.
• If you selected
[F4] (20 mA)
, proceed to
20 mA Option
on the next page.