Servomex NanoTrace DF-760E, Instruction Manual

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User Interface DF-760E 83
7.6.2.6 Averaging Filter
Figure 74: Oxygen Signal Filter Control Screen
This screen displays the offset between the displayed reading O2 AVG and the real-time
reading O2 RAW. The difference between the two readings illustrates the time lag and
noise reduction effects of the filter while in use. Observing the relative changes to these
readings can help the user to establish optimum filter settings for a specific process or
application.
Three types of electronic digital filtering are available which are used to condition the
output signal to smooth out noise and spikes.

Normal

Low LDL

Ultralow LDL
The use of one particular technique over another will depend upon the noise level or speed
of response required for the application. Selecting
Ultralow LDL will provide for the least
noise in the signal but the slowest response time. Selecting Normal will yield a faster
response but a noisier signal. Units are shipped from the factory with the setting at Low
LDL which provides a useful trade-off of noise with respect to response for most
applications.
The user also has the ability to enable an additional Transient Rejection algorithm if
spikes are observed on the signal. If a spike occurs, the algorithm will delay any additional
data from entering the buffer for a given time interval. During this interval, the system
determines if the spike represents a true change to the baseline or is just a transient. If
merely a transient, the data is not transferred to the buffer. This method of transient
rejection is useful for eliminating artifacts, but will result in delays of up to one minute
reporting the actual data when a real oxygen intrusion really occurs.
7.6.2.7 Upload Sensor Data
The Oxygen Sensor Data screen displays the calibration values that were established when
the oxygen sensor and analyzer were calibrated at the factory (new) or when a replacement
oxygen sensor was last installed.