Emerson Rosemount 3308, Reference Manual

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Reference Manual
00809-XXXX-4811, Rev AA
February 2012
A-5
Rosemount 3308
PRELIMINARY
PERFORMANCE SPECIFICATION
General
Reference Conditions Rigid Single Lead probe, 77 °F (25 °C) water
Reference Accuracy
Repeatability
± 0.04 in. (1 mm)
Ambient Temperature Effect Less than 0.01% of measured distance per °C
Measuring Range
Transition Zones These zones are areas where
measurements are non-linear or have
reduced accuracy. If measurements are
desired at the very top of a tank, it is
possible to mechanically extend the nozzle
and use a coaxial probe. The upper
transition zone is then moved into the
extension. See Table A-3 on page A-7.
Measuring Range and
Minimum Dielectric Constant 16 in. (0.4 m) to 77 ft. (23.5 m)
See Table A-4 on page A-7 for each probe’s measuring range and minimum dielectric constant. Due to the
measuring range depending on the application and factors described below, the values are a guideline for
clean liquids. For more information, ask your local Emerson Process Management representative.
Different parameters (factors) affect the echo and therefore the maximum measuring range differs
depending on application according to:
• Disturbing objects close to the probe
• Media with higher dielectric constants (

r) give better reflection and allow a longer measuring range
• Surface foam and particles in the tank atmosphere may affect measuring performance
• Heavy coating or contamination on the probe should be avoided since it can reduce measuring range
and might cause erroneous level readings
Note: See Table A-5 on page A-7 for the measuring range when using the Remote Housing.
Interface Measuring Range Target applications include interfaces between oil; oil-like and water; and water-like liquids with a low (<3)
upper product dielectric constant and a high (>20) lower product dielectric constant. For such applications,
the max measuring range is only limited by the length of the coaxial, rigid twin and rigid single lead probes.
Note: For other product combinations, consult your local Emerson Process Management representative.
Environment
Vibration Effect Wireless output unaffected when tested per the requirements of IEC60770-1 field or pipeline with high
vibration level (10-60 Hz 0.21 mm displacement peak amplitude / 60-2000 Hz 3g).
Wireless output unaffected when tested per the requirements of IEC60770-1 field with general application
or pipeline with low vibration level (10-60 Hz 0.15 mm displacement peak amplitude / 60-500 Hz 2g).
Electromagnetic
Compatibility (EMC) Meets all relevant requirements of EN 61326-2-3:2006
Built-in Lightning Protection Meets EN 61000-4-4 Severity Level 4 and EN 61000-4-5 Severity Level 4
Upper Reference Point
Upper Transition Zone
Maximum
Recommended
Measuring Range
Lower Transition Zone
Lower Reference Point
Lower Transition Zone
For a flexible single lead probe with
chuck, the lower transition zone is
measured upwards from the upper part
of the clamp.
Lower Transition Zone