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This dialog appears if you do the following:
Use the Accelerometer Sensor Information dialog to view and edit the specifications needed to identify the data stream of a single accelerometer and for all of its channels. Additionally, the software must convert the data streams arriving using user-specified conversion parameters.
When the Accelerometer Manager module successfully connects to the RTPD service, it receives all MRF (Multiplexed Recording Format) data streams available at the RTPD service. The origins of these data streams may be several accelerometers connected to several REFTEK Data Acquisition System (DAS) units. For identifying a specific data stream one must enter or select the unit ID of the DAS and the ID of the specific data stream.
DAS ID: Specifies the unique unit ID of the DAS. If the module is successfully connected to the RTPD service, the RTPD automatically provides the IDs of all DAS units streaming data to it. For selecting a DAS, click the arrow-down button. Alternatively, you may enter or copy the unit ID into the value field.
Stream ID: Specifies the numeric ID of the accelerometer data stream. Either enter a number or use the arrow-up and arrow-down buttons. Use your data sheets to select the stream ID matching the individual accelerometer.
Sample rate: Only available for editing if the data format is PASSCAL. Specifies the number of samples per second. The PASSCAL format does not send the sample rate information in its header section. Once per hour, the Accelerometer Manager module receives the message containing the value and automatically updates the settings. However, if you want ot use the data before the first channel information data set arrives, edit the Sample rate value for it to match the incoming sample rate.
REFTEK accelerometers are available as uni-axial and tri-axial sensors. Tri-axial accelerometers provide their data streams in three channels, which can be assigned to the axis directions by giving the channel a numeric ID.
X Channel ID / Y Channel ID / Z Channel ID: These properties specify the unique numeric IDs of the three channels. Either enter a number or use the arrow-up and arrow-down buttons.
The data arriving at the module, contains, for each of the channels, the counts from the Analog/Digital (A/D) converter of the accelerometer. For converting the counts to ground units a bit weight and a scale factor are applied. The value of the scale factor is printed on the accelerometer sensor device. The bit weight value for the DAS unit is determined and stored in the DAS unit at REFTEK during factory calibration. Once per hour, the Accelerometer Manager module receives the message containing the values for both parameters, displays it in its Messages view and automatically updates the settings for these parameters.
When setting up the Accelerometer Manager module, therefore, one can either wait for the message to arrive or key in the appropriate values.
Warning - The message containing the bit weight and scale factor is only complete if the scale factor has been keyed in correctly into the DAS configuration UI. If not, the message is incomplete and the property will never be updated. For making sure that the message is complete, use the Receiving Info module-view: The message should contain the bit weight and scale factor values. If there is no scale factor value in the message, it shows the string "Unknown".
What happens if the system has already channel information, but the values arriving from the DAS differ from those stored in the system? This may happen, for example, if at either side of the system (at the DAS or at the module properties) a value was mistyped. In this case, a message appears in the Receiving Info view for that accelerometer and epoch that contains a warning on the mismatch of the values.
X Weight / Y Weight / Z Weight: These properties specify the bit weights per channel in [mvolts/count].
X Scale factor / Y Scale factor / Z Scale factor: These properties specify the sensor sensitivity as a scale factor per channel in [volts/g].