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WIKA operating instructions EMM Calibration Sled
PN 0019408001A 08/2018 EN
EN
3. Program operations and procedures
4. Select Calibrate button. The next screen should appear as shown in Figure 2.3.
Figure 2.3 – Calibration/data screen
The following fields may be updated:
• Calibration Date – a six digit number must be entered. The calibration date entered should be formatted in the form “MMDDYY”
or “DDMMYY” so that the Mensor instrument will convert the date correctly for the different locales available from the supported
languages.
• Cert # – a 16 character string can be entered. The Cal ID# is an arbitrary string you may use to identify the calibration of the
sensor.
• Units – Displays the native units of the sensor
• Zero – a value between ± 0.1% of range, usually close to 0. This is the calibration offset used to adjust the zero reading of the
sensor. The zero offset is unit based so enter the value in the native units of the sensor.
• Span – a value between 1 ± 0.15% of range, usually close to 1.0. This is the calibration correction multiplier used to adjust the
span reading of the sensor.
5. The tool is divided into four separate sections corresponding to each sensor in the EMM.
• Head temperature is the Platinum Resistive Thermometer (PRT) for head temperature measurement that has an external probe.
• Ambient Temperature is the internal ambient temperature sensor.
• Ambient Pressure is the internal barometric pressure sensor.
• Relative Humidity is the internal humidity sensor.
Observe each reading to determine if sensors are live.
6. The PRT should be calibrated by probe immersion in a precision temperature bath against a standard that has accuracy as
previously described. Multiple choices exsist for calibration. Including forced zero and/or span adjustment with the same named
buttons. The 2-pt Cal is a way to calibrate at two discrete tempertures. Linearity is a way to calibrate multiple discrete temperture
points and auto-linearizing the PRT.
7. All other sensors can be calibrated using the Zero, Span or 2-pt Cal buttons.
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Considering the accuracy requirements of these sensors, at Mensor we find that a simple single point calibration using the
Zero button under ambient conditions is sufficient.
8. If pressure is to be applied to the barometric sensor for calibration, tubing and an adaptor fitting have been provided. One end
of the tubing is inserted into the hole in the EMM’s case. The tubing can then be applied over the sensor barb. The other end of the
tubing can be connected to a pressure source with the adaptor fitting. The adaptor fitting has a 7/16-20 male thread
Head temperature linearity
Selection of the linearity button brings up the following screen.