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Measuring range, Interface, Measuring range -9 interface -9 – Emerson Guided Wave Radar Level and Interface Transmitters 3300 User Manual

Page 21: Rosemount 3300 series, Reference manual

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Reference Manual

00809-0100-4811, Rev CA
February 2006

2-9

Rosemount 3300 Series

Measuring Range

The measuring range differs depending on probe type and characteristics of
the application. The values given in Table 2-4 can be used as a guideline for
clean liquids.

Table 2-4. Measuring Range

The maximum measuring range differs depending on application according
to:

Disturbing objects close to the probe.

Media with higher dielectric constant (

ε

r

) gives better reflection and

allows a longer measuring range.

A calm surface gives better reflection than a turbulent surface. For a
turbulent surface the measuring range might be reduced.

Surface foam and particles in the tank atmosphere are also
circumstances that might affect measuring performance.

Coating/contamination can reduce the measuring range.

Disturbing EMC environment in tank.

Interface

Rosemount 3302 is the ideal choice for measuring the interface of oil and
water, or other liquids with significant dielectric differences. It is also possible
to measure interface with a Rosemount 3301 in applications where the probe
is fully immersed in the liquid.

Figure 2-6. Interface
measurement with a Rosemount
3302 and a Rosemount 3301
(fully immersed probe).

Coaxial, Rigid twin, Flexible twin and Rigid Single lead probes can be used for
measuring interfaces. The coaxial probe is the preferred choice for clean
liquids and when the bridle is not fully immersed. In applications with a fully
immersed probe, the twin lead probes are recommended for nozzle
installations, and the rigid single lead probe is best for bridle mounting.

Coaxial

Rigid Twin Lead

Flexible Twin Lead

Rigid Single Lead

Flexible Single Lead

Maximum Measuring Range

19 ft 8 in. (6 m)

9 ft 10 in. (3 m)

77 ft 1in. (23.5 m)

9 ft 10 in. (3 m)

77 ft 1in. (23.5 m)

Minimum Dielectric Constant at Maximum Measuring Range

Standard & HP:
1.4
HTHP:

2.0 up to 13 ft (4 m)

2.5 up to 19 ft 8 in. (6 m)

1.9

1.6 up to 33 ft (10 m)

2.0 up to 66 ft (20 m)

2.4 up to 77 ft 1 in. (23.5 m)

2.5
(1.7 if installed in a
metallic bypass or stilling
well)

2.5 up to 36.1 ft (11 m)

5.0 up to 66 f (20 m)

7.5 up to 77 ft 1 in. (23.5 m)

BRI

D

LE_

INTERFACE_

C

A

Level

3302

3301

Interface Level

Level=Interface Level