Emerson Process Management 5300 manual Disturbance Echo Handling, Amplitude Threshold Curve

Reference Manual

00809-0100-4530, Rev BA July 2009

Rosemount 5300 Series

DISTURBANCE ECHO HANDLING

When the Basic Configuration is done, the transmitter may need a fine-tuning to handle disturbing objects in the tank. The Amplitude Threshold Curve (ATC) function can be used for disturbance echo handling with the Rosemount 5300 Series transmitter.

Amplitude Threshold Curve

As shown in Figure 7-5,the ATC can be designed to filter out single disturbing echoes by adapting the curve around the corresponding amplitude peak. It is important in this case that the disturbance is fixed at a certain tank level.

Disturbing echoes which may appear different from time to time can be filtered out by raising the whole ATC.

Figure 7-5. Disturbing echoes can be filtered out by creating an amplitude threshold.

mV	Measurement signal
Amplitude,
	Disturbing object	Amplitude Threshold Curve
	Distance, m

Disturbances at the Top of the Tank

In addition to using the ATC, the Rosemount 5300 transmitter supports alternative methods to filter out disturbances at the top of the tank, such as the Trim Near Zone and the Upper Null Zone functions, which can be used to handle disturbances from narrow nozzles or nozzles with rough edges. See “Handling of Disturbances from Nozzle” on page C-4for more information.

7-7