Fourier MultiLab, User Manual

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Chapter 2 MultiLab Software 61
2.5.6. Calibrating the Sensors
MultiLab enables you to calibrate any of the sensors manually. This calibration is
much more accurate than the calibration performed by MultiLogPRO. With MultiLab,
you can calibrate the sensor using two points instead of the
one point automatic
offset calibration used by MultiLogPRO:
1. Connect MultiLogPRO to the PC.
2. Select the Calibrate sensors option from the Logger menu
3. Choose a sensor from the Select sensor drop list and click OK
4. Click the Calibration tab.
5. Enter a distinct real value in each of the Real Value edit boxes and
the corresponding measured values in each of the Measured Value
edit boxes (The measured values are the values displayed by
MultiLab when measuring the two real values.
6. Click OK
The calibrated sensor parameters will be saved, so there is no need to calibrate
MultiLogPRO every time you run the MultiLab program.
To reset to the default calibration for any sensor, select the sensor and click Restore
defaults .
2.5.7. Define a Custom Sensor
Ordinarily, you will not need to use this option, but MultiLab enables the user to
define additional custom sensors. This is a useful tool for when MultiLogPRO is
communicating with many sensors from
different vendors.
Any additional sensor that you would like to connect to MultiLogPRO must comply
with the following restrictions:
•
The sensor ’ s output must be greater than or equal to 0V and less than or
equal to 5V . Remember that all sensors transform actual data into electrical
data, so the electrical output should remain between 0 and 5 volts.
•
The sensor Transfer Function (sensor output voltage changes vs. the sampled
phenomenon changes) must be a linear Transfer Function.
•
The sensor must have a code resistor in order to be automatically identified. If
the sensor does not have a code resistor, you will have to work in 8 inputs
mode and select the sensor manually.
To determine whether your sensor has a code resistor or not, simply plug it in to
MultiLogPRO (while in
Auto ID mode) and see if MultiLogPRO displays the setup
menu and the sensor name.
Refer to the appendix to learn how to add a code resistor to your custom sensor.
To define a new sensor:
1. Connect MultiLogPRO to the PC.
2. Select Define new sensor from the Logger menu to open the
Define new sensor dialog box: