User`s manual

7800 Series Hysteresisgraph System User's Manual
4-20 Operation
Mode 1 Calibration (Continued)
8. Ensure the Hall Probe Serial Number is displayed. This number is the EEPROM serial number stored in the
connector shell of the Hall probe currently attached to the system.
9. Place the Hall probe in a zero gauss chamber and click the Zero Probe button.
NOTE: You may bypass Step 9 if less than 1 day has elapsed from last zero. The “Time Elapsed Since Last
Zero” date and time is displayed. If less than 1 day, an additional Bypass Zero button is displayed.
10. When the zero probe process is complete, click the Accept button. This ends Mode 1 calibration.
4.2.2 Mode 2 Calibration (Air Flux)
Mode 2 calibration is intermediate in complexity and determines H and B coil sensitivities against a calibrated
electromagnet field. The combined effect of air gap flux, physical coil sensitivity, fluxmeter integration, area
compensation, and loading impedance determines calibration sensitivity. Because the coil and fluxmeter are
calibrated together, coil geometry changes and electronic variations are minimized.
1. Repeat Paragraph 4.2.1, Steps 1 thru 10. When these steps are successfully completed, you will see the
AutoSet H dialog box.
2. Ensure there is a reasonable reading in the “Field in EM Gap” window and that the target field value is
displayed in the “Desired Field” window.
NOTE: The value in the “DacOut” window is the number of Amps being sent to the electromagnet.
3. Place the Hall Effect probe in the electromagnet gap. The value is continuously monitored and used as a
feedback parameter to run the control loop which sets the electromagnet field.