Rosemount 5300 Series, Справочное руководство

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Advanced Configuration
May 2016
Reference Manual
00809-0100-4530, Rev DD
313
Advanced Configuration
Figure C-12. Echo Tracking in RRM
Automatic echo tracking settings are enabled by default. In the Advanced Configuration
window the Echo Tracking settings Echo Timeout and Close Distance can be also be set
manually.
Use automatic echo tracking settings
When this check-box is selected, the transmitter automatically sets the echo tracking
parameters to a constant value based on the configured tank environment and
measurement mode.
Echo Timeout: defines the time in seconds before the device should start to search for a
surface echo outside the Close Distance window after it was lost. After an echo was lost, the
device does not start searching (or set Invalid Level) until the specified time has elapsed. In
some applications, especially with solid products or applications with foam, the surface
echo may disappear for periods of time. This value can be increased to prevent the device
from entering alarm mode too early after the surface is lost.
Close Distance: defines a window centered at the current surface position where new
surface echo candidates can be selected. The size of the window is ±Close Distance. Echoes
outside this window will not be considered as surface echoes. The device will without delay
jump to the strongest echo within this window. This value can be increased if there are rapid
level changes in the tank. If the value is too large the device might select an invalid echo as
the surface echo.
Damping
The Damping parameter defines how fast the device reacts to a change of the level value
(step response). A high value makes the level steady but the device reacts slowly to level
changes in the tank. A low value makes the device react quickly to level changes but the
presented level value can be somewhat jumpy. The default value is 2 seconds. Note that
increasing the damping value will also prolong the system response time. The damping
value can also be changed from the
Output , General tab.