COMPASS allows for data averaging when the data acquisition method is “manual”. A device, such as a DUT, can have manual data input and still allow for multiple samples to be averaged.
The traditional approach to averaging an output is to use a remote interface for automated data acquisition. The remote interface (ie: RS232, IEEE, TCPIP) allows for the rapid-fire sending of a command to query the output and processing the response, and doing this many times during a timed interval. The advantage of averaging is it allows for the partial cancelling of measurement noise for the benefit of recording a more representative value for the measurement. This works well for static pressure calibrations where measurements are commonly made at a near-steady state condition.
When a device does not have a remote interface then data can only be inputted into COMPASS using manual data acquisition – the operator types in the pressure. COMPASS allows for multiple updates to the Raw DUT Pressure during the averaging stage and treats each input as a data sample.
- If Timed Average is enabled for a COMPASS test and the DUT data acquisition is defined as manual input, then COMPASS will process any and all of the operator inputs into the Raw DUT Pressure field. Each input is treated as a measurement sample.
- At the end of the averaging period an input box appears for the Manual Data Entry for the DUT. This input is ignored by COMPASS if multiple data inputs have been entered during the averaging period.
This screen capture shows the Raw DUT Pressure field where the DUT pressure is manually updated during the averaging period.
The following screen capture is the Manual Data Entry input box for the DUT which appears at the end of the averaging period. Note: the value of “0.00” is ignored as a measurement sample when multiple updates are made during the averaging period:
This screen capture shows the data grid where six (6) updates were made to the Raw DUT pressure and it was logged as six data samples: