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Reference Manual
00809-0100-4026, Rev HA
Section 5: Basic Configuration/Start-up
November 2014
Basic Configuration/Start-up
Pipe diameter
When the transmitter is mounted in a still-pipe, the inner diameter of the pipe must be
specified. The pipe diameter is used to compensate for the lower microwave propagation speed
inside the pipe. An incorrect value gives a scale factor error. If locally supplied still-pipes are
used, make sure the inner diameter is noted before the pipe is installed.
Transition zone
The measurement accuracy is reduced within the transition zone region 6 in. (150 mm) from
the lower end of the antenna. It is recommended that the Upper Range Value (20 mA) be set
outside the transition zone.
5.3.3 Process conditions
Describe the conditions of the tank according to the tank environment parameters for process
conditions listed below. For best performance, choose only if applicable, and no more than
two options.
Rapid level changes
Optimize the transmitter for measurement conditions where the level changes quickly from the
filling and emptying of the tank. As a default standard, a Rosemount 5400 Series transmitter is
able to track level changes of up to 1.5 in./s (40 mm/s). When the Rapid Level Changes
check-box is selected, the transmitter can track level changes of up to 8 in./s (200 mm/s).
Turbulent surface
This parameter should be used if the tank has a turbulent surface. The reason for the turbulence
might be splash loading, agitators, mixers, or boiling product. Normally, the waves in a tank are
quite small and cause local rapid level changes. By setting this parameter, the performance of
the transmitter will improve when there are small and quickly changing amplitudes and levels.
Foam
Setting this parameter optimizes the gauge for conditions with weak and varying surface echo
amplitudes, such as foam. When the foam is light and airy, the actual product level is measured.
For heavy and dense foam, the transmitter measures the level of the foam’s upper surface.
Product dielectric range
The Dielectric Constant is related to the reflectivity of the product. By setting this parameter,
measurement performance can be optimized. However, the transmitter will still be able to
perform properly, even if the actual Dielectric Constant differs from the configured value.
Solid product
Setting this parameter optimizes the device for solid products, for example concrete or grains.
For instance, this parameter can be used when the application is a silo with product pile-up. The
transmitter will be optimized for weak echoes and a sloping surface which is typical when
measuring at solid materials. This option shall only be used for a Rosemount 5402 with a 4” cone
antenna.
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