Operating Manual

Chapter 5 Radar Fine Tuning Accu-Wave
5-8 TN Technologies
but will allow any echoes beyond the level (lower) to be accepted without considering the
range gate.
Note: If you want to use an agitator reject time entry of “forever,” enter 65535
seconds.
Range Gate Weighting Factor (GWF)
A range gate weighting factor (GWF) can be applied to echoes that fall within the range
gate. A GWF value greater than 1 gives additional preference to echoes within the range
gate during the processing to select the best candidate. A GWF value less than 1 reduces
the preference given to echoes within the range gate.
You may also affect the system response by changing the height (span) of the range gate.
The default value for the range gate height is 25 cm (~10 in). Entering a larger value for
the range gate height would increase the number of echoes considered valid and which
could be used to update the current measurement values.
Using a larger range gate height and a short time constant value would allow the range
gate to move quickly as the actual material level moves and would give the system a good
chance of getting usable echoes from the material before it moves out of the range gate.
Using a smaller range gate height can improve accuracy in turbulent applications but can
also slow response depending on the range gate delay used.
The “long” range gate delay configuration would be used to deal with extended process
changes such as a filling stream or the actual level going outside the range of interest. In
such cases, the range gate delay should be set to the longest expected duration of the
“unusual” process condition. A greater time-out should only result from a lost level
condition.
Response Time, Lost Echo and Agitator Reject Setup Menus
The following table describes the individual menu items available under the Response
Time, Lost Echo and Agitator Reject Setup menu group. Menu items that require the
“Service only items” to be enabled include the notation [Service only item].