Setra System Model 370 - Manual (Page 34)

lI.2 SPAN CALIBRATION
To perform the span calibration on the Model 370, it is necessary to apply both the
zero and the full scale pressures, as in the following procedure:
1. Make certain the gauge is in a stable temperature environment for several
hours before calibration.
2. Press SETUP, then press SPAN. The display will read "APPLY" and the
pressure required for zero calibration.
3. Apply the indicated pressure from a high accuracy standard.
4. Press SETUP. The display will read "APPLY" and the pressure required for
full scale calibration.
5. Apply the indicated pressure from a high accuracy standard.
6. Press SETUP. The gauge will take data, adjust its' zero and span calibra-
tions, and return to normal display mode.
If the new zero and full scale data is too far from the factory calibration, the gauge will
display "UnAbLE". Verify the applied pressures. If they are correct, contact a Setra
Applications Engineer for assistance.
28