April 2004
9-24 Servicing the PT878GC
Calibrating Inputs (cont.)
4. Connect the current source to the input and set it to deliver the
value entered in the previous step.
5. Press the [X] arrow key to move to the Read box, and then
press [ENTER] to read the low input.
6. The next prompt asks for the value to which you want to set
the high input (20 mA).
a. Press [ENTER] to open the text box.
b. Use the numeric keys to enter the recommended value.
c. Press [ENTER] to confirm your entry.
7. Connect the current source to the input and set it to deliver the
value entered in the previous step.
8. Press the [X] arrow key to move to the Read box, and then
press [ENTER] to read the high input.
9. Press the [T] key to move to the Calibrate box, and press
[ENTER] to calibrate the inputs.
10.At this point, you have two options:
a. If you are unsatisfied with the calibration, you can reset the
inputs to factory defaults. Press the [X] arrow key to move
to the Reset box, and then press [ENTER] to undo the
calibration.
b. If you are satisfied with the calibration, press the [T] key
to return to the Input# prompt, and repeat steps 2 through 8
for the other input.
You have completed calibrating the inputs. To leave the Inputs
window,
•Press the [S] key to return to the Inputs tab, and the [W]
arrow key to move to the Outputs tab.
•Press [F2] (Cancel) to return to Operate Mode without
confirming the changes.
•Press [F3] (OK) to confirm the new data. The PT878GC
returns to Operate Mode.