Super Systems Simple Dew - Manual (Page 9)

Simple Dew Digital Dew Point Analyzer Operations Manual
Super Systems Inc. Page 9 of 18
4.1 Leave the sensor in the calibration salt for a minimum of eighteen (18) hours. It is
acceptable to leave the sensor in the salt solution for a longer period of time, even a
few days, if desired.
5.0 Begin the 75.3% (Span) calibration process.
5.1 After leaving the sensor in the salt for at least eighteen (18) hours, turn the unit
on (if it isn’t on already).
5.2 Simultaneously press the “75.3%” and “Calibration” buttons on the
microprocessor board.
6.0 Verify the 75.3% (Span) calibration.
6.1 Leave the sensor in the 75.3%RH calibration salt.
6.2 Record the temperature and the dew point of the sensor. Since there is no display
on the instrument, you will need to measure the voltage from the microprocessor
board and translate that into the appropriate measurement.
6.2.1 To determine the sensor temperature, measure the voltage between pins
5(+) and 9(-) on the microprocessor board. The voltage will be between 0
and 1VDC. Use the chart in Appendix A to determine the temperature in
°F, or use Appendix B to determine the temperature in °C.
6.2.2 Temporarily record the sensor temperature.
6.3 Look up this temperature in Appendix “C” (Determining the Dew Point in °F) or
Appendix “D” (Determining the Dew Point in °C). Appendix C will show the
temperature values in Fahrenheit, and Appendix D will show the temperature values
in Celsius.
6.4 Next to the appropriate sensor temperature, note the number in the
corresponding column titled “75.3%”. This will match the measured dew point,
which can be verified wherever the dew point is displayed.
7.0 After the 75.3% (Span) calibration has been completed, remove the sensor from the
calibration salt and replace the cap on the salt.
7.1 Leave the sensor probe in the gland and while the unit is still on, allow it to
achieve equilibrium at the ambient atmosphere in the room. This is accomplished by
simply leaving the sensor exposed to ambient air for between two and three minutes.
You will know when this has been accomplished when the numbers on the display
begin to stabilize.
8.0 Install the sensor probe into the 11.3% salt solution.