Emerson Process Management rosemount 3300 series manual 3ORWWLQJWKH Phdvxuhphqwvljqdo

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00809-0100-4811, Rev AA October 2002

Rosemount 3300 Series

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Figure 6-2. Waveform plot in RCT

WAVEFORMPLOT_GENERAL

The Radar Configuration Tool (RCT) has powerful tools for advanced troubleshooting. By using the Waveform Plot function you get an instant view of the tank signal. Measurement problems can be solved by studying the position and amplitude of the different pulses.

<￿￿￿￿￿￿￿￿￿￿H￿￿￿To plot the measurement signal:

1. Start the Radar Configuration Tool program.

2. Choose the 9LHZ>3ORWWLQJ menu option, or choose the Plotting icon in the RCT workspace (Advanced page at the left side of the workspace) and click the Read button.

In a typical measurement situation the following pulses appear in the diagram:

3￿ - Reference pulse. This pulse is caused by the transition between transmitter head and probe. It is used by the transmitter as a reference at level measurements.

3￿ - Product surface. This pulse is caused by a reflection on the product surface. In Measurement Mode=Interface when Immersed Probe however, P2 indicates the interface since the surface of the upper product is ignored.

3￿ - Interface or probe end. This pulse is caused by reflection on the interface between an upper product and a bottom product with a relatively high dielectric constant. It may also be caused by the probe end if there is no product above. This pulse is shown when the transmitter is in Measurement Mode=Level & Interface.

Different amplitude thresholds are used in order to filter out unwanted signals. The following amplitude thresholds are used for the 3300 transmitter:

7￿ - amplitude threshold for detection of the Reference pulse P1.

7￿ - amplitude threshold for detection of the product level peak P2.

7￿ - amplitude threshold for detection of the interface level peak P3.

7￿ - amplitude threshold that is used to detect whether the probe is fully immersed in the upper product or not.

Normally the thresholds are adjusted to approximately 50% of the signal peak amplitdue. To adjust the $PSOLWXGH￿7KUHVKROGV open the Advanced section

in the RCT Project Bar and choose Device Commands>Details>Set Nominal Thresholds.

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