Tuttnauer 2540 EHS, Technician Manual

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5.2 Calibration Theory - Error Compensation:
The system’s error compensation is based on a calculation involving
two points. These points represent the low and high end of the
autoclaves operating temperature or pressure range.
Each point has two values; one value is the “A” actual (measured)
reading of either temperature or pressure (from a PT simulator,
independent thermometer or pressure gauge). The other value is the
“R” the reading from the autoclave’s digital display of either
temperature or pressure. By entering these values into the unit through
the keypad the system is able to calculate a compensation factor that
will correct the digital display and allow it to accurately return the
actual temperature or pressure.
Note: The two points that are selected will define the range of the error
compensation. Although points above and below are not part of
the compensation, the calibration produces a linear compensation
and these values will be accurate.
Note : The temperature can be calibrated in either °F or °C, depending
on what units the machine is set to display.
Note: The pressure calculations are always done in Absolute pressure
(Absolute pressure = atmospheric pr 14.5)
The calibration steps that follow will allow you to automatically
correct the displayed temperature and pressure so it accurately reflects
the actual temperature and pressure. All you need do is input the
appropriate data (actual and displayed values) into the system through
the keypad and the on board computer will do the rest.
Note: It is necessary to know the actual and displayed values prior to
entering the calibration mode.
5.3 Equipment needed for calibration
— A PT100 simulator
— Saturated Steam Table (para 7)
5.4 Calibration Procedure
Calibration consists of three (3) parts and needs to be preformed in the
following order. It is not advisable to perform only a partial calibration
1. Check that the atmospheric pressure parameter is set correctly (see
sec 8.2.17)
2. Collect and enter temperature data
3. Collect and enter pressure data
5.4.1 Connecting the test equipment
Remove the outer cabinet
Disconnect the PT100 temperature sensor from the JP2
connector on the ANL_T2 board
Connect the PT100 simulator to JP2