Super Systems 1500 VRSD - Manual (Page 6)

Model 1500 VRSD Operations Manual
Super Systems Inc. Page 6 of 28
Dew Point Sensor
Factory Calibration
Factory calibration is recommended every six months if the unit is used regularly. SSi’s
calibration is NIST traceable and includes a numbered “Certificate of Calibration”. This
certificate also indicates the accuracy of the analyzer before and after calibration.
Please contact Super Systems at (513) 772-0060 for more information regarding this
service.
Field Calibration
It is also possible to calibrate the VRSD in the field, which will require the optional
calibration kit (Part Number 31030) and a voltmeter that will allow you to measure
between 0 and 1 volt DC. Since there is no temperature display on the instrument itself,
the voltage from the sensor circuit board will have to be translated into a temperature
measurement for the purpose of verifying the calibration. The instructions for doing
this are contained in this document along with reference charts to aid in the
interpretation of the voltages.
The calibration kit consists of two bottles of saturated salt solution in which each bottle
generates a precise relative humidity percentage (R.H.%) value. One bottle is 11.3%
R.H., and the other is 75.3% R.H. These two specific calibration points are already pre-
programmed into the microprocessor board.
1.0 Open the unit.
1.1 Undo the latches on the side of the enclosure.
2.0 Locate the key components within the unit.
2.1 The microprocessor board is located in the front right side of the unit. This
board contains three very small buttons that are used for calibration. Two
are next to one another, and they are marked “75.3%” and “11.3%”, while the
other has no label. The unmarked button is the “Calibrate” button. The
approximate locations of each button are shown on this diagram: