Omega Engineering CYD201 and CYD208 manual SoftCal Calibration Procedure

OMEGA Model CYD201/CYD208 User’s Manual

SoftCal™ calibrations are made at three temperature points: liquid helium (4.2 K), liquid nitrogen (about 77 K), and 305 K. Below is the accuracy* of the CY-7-SD-13 sensor:

+0.5 K	2 K to <30 K		+0.25 K	345	K to <375 K
+0.25 K	30	K to <60 K	+1.0 K	375	K to 475 K
+0.15 K	60	K to <345 K

*These values generally apply to all silicon diode sensors. Only two-point SoftCal™ calibrations appropriate for CY-7 series Band 11, 11A sensors.

This section covers the SoftCal™ Calibration Procedure (Paragraph 3.6.1), Verifying SoftCal™ Operation (Paragraph 3.6.2), and Erasing SoftCal™ Compensations (Paragraph 3.6.3).

3.6.1SoftCal™ Calibration Procedure

1.Turn on thermometer 30 minutes prior to operation.

2.Place the SET switch in position 1.

3.Hold UNITS until 0 kelvin (or equivalent in °C or °F) displays. The key acts as a toggle. If the display rises, release and press again.

4.Press CAL ENABLE on rear panel with a pen tip. The display reads "-SOF-" to indicate the unit is ready to erase the current SoftCal™ calibration. Within 2 seconds press UNITS again. The temperature display changes from "-SOF-" to the current SoftCal™ setting.

5.Hold UNITS until the sensor temperature displays. For example, if setting SoftCal™ for liquid helium, the display reads 4.2 K. If setting for ice point, the display reads 0 °C.

6.Verify sensor stabilization at calibration temperature.

7.Press CAL ENABLE again. "-SOF-" again displays to indicate the unit is ready to accept the calibration point. Within 2 seconds, press UNITS to enter a new calibration point. (If UNITS is not pressed within 2 seconds, the display returns to the alarm temperature). After 15 seconds, the alarm setpoint temperature displays.

8.To enter more than one point, go back to step 5. NOTE: One point may be entered between 1.4 K to 9.9 K. No point may be entered between 10 K and 40 K. Two points may be entered above 40 K.

9.Return the SET switch to position 0.

3-4 Operation