Rosemount Process Radar in Refining Applications-Best Practices for Installation and Commissioning Manuals & Guides

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Process Radar in Refining Applications

Best Practices for Installation and Commissioning

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Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Rosemount Process Radar in Refining Applications

Best Practices for Installation and Commissioning

The products described in this document are NOT designed for nuclear-qualified
applications.

Using non-nuclear qualified products in applications that require nuclear-qualified hardware
or products may cause inaccurate readings.

For information on Rosemount nuclear-qualified products, contact your local Rosemount
Sales Representative.

This product is designed to meet FCC and R&TTE requirements for a non-intentional
radiator. It does not require any licensing whatsoever and has no tank restrictions
associated with telecommunications issues.

This device complies with part 15 of the FCC rules. Operation is subject to the following two
conditions: (1) This device may not cause harmful interference, and (2) this device must
accept any interference received, including interference that may cause undesired
operation.

Cover Photo: Cover.tif

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Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Table of Contents

SECTION 1
Introduction

SECTION 2
Installation
Considerations

SECTION 3
Refining Applications

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Installation Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Chambers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Transmitter Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Flushing Connections and Vents . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Chamber Fabrication and Probe Selection. . . . . . . . . . . . . . . . . . 2-5

Existing Chambers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8

Setting Range Values - Three Options. . . . . . . . . . . . . . . . . . . . . 2-8

Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10

Pipes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10

Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12

Recommended Mounting Position . . . . . . . . . . . . . . . . . . . . . . . 2-12

Nozzle Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14

Process Isolation for Service . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17

Probe and Antenna Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Refining Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Chambers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

High temperature at low to moderate pressure -

Level Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

High Temperature and High Pressure -

Level Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

High Temperature and High Pressure -

Level and Interface Measurement . . . . . . . . . . . . . . . . . . . . . . . . 3-6

Standard Temperature and Standard Pressure -

Level Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

Standard Temperature and Standard Pressure -

Interface Measurement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8

Pipes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9

Desalters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9

Liquefied Gases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9

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Rosemount Radar Level Transmitters

Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10

Ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10

Solids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10

Storage Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12

Tanks with agitators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12

Compressor tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13

Tanks with very rapid level changes. . . . . . . . . . . . . . . . . . . . . . 3-13

Applications to limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14

Reference Manual

00809-0200-4530, Rev AB

September 2009

SECTION 4
Commissioning

SECTION 5
Measurement Validation
at Operating Conditions

SECTION 6
Troubleshooting
Procedures

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Trim Near Zone (5300 Series only) . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Store Backup and Verification Files . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

On the Bench Test (optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2

Measurement Validation at Operating Conditions . . . . . . . . . . . . . . . . 5-2

Step 1: Verify the Correctness of Level Reading . . . . . . . . . . . . . . . 5-2

Step 2: Analog Output Signal Validation . . . . . . . . . . . . . . . . . . . . . 5-3

Step 3: Echo-Curve Verification at Operating Conditions . . . . . . . . 5-4

Step 4: Transmitter Diagnostics Review . . . . . . . . . . . . . . . . . . . . . 5-4

Step 5: Monitor Level while Emptying . . . . . . . . . . . . . . . . . . . . . . . 5-5

Step 6: Echo-Curve Verification with Empty Tank . . . . . . . . . . . . . . 5-6

Step 7: Monitor Level while Filling . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2

Echo Curve Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3

Echo Curve Constituents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3

5300 Threshold Settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5

5400/5600 Threshold Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5

Common Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6

Sources of Measurement Error . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11

Installation and Location Errors . . . . . . . . . . . . . . . . . . . . . . . . . 6-11

Geometries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-12

Analog Output Settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-12

Incorrect Dielectric Constant of the Upper Product . . . . . . . . . . 6-13

Submerged Probes with Air gap. . . . . . . . . . . . . . . . . . . . . . . . . 6-14

Incorrect Vapor Compensation. . . . . . . . . . . . . . . . . . . . . . . . . . 6-15

Reconciling Radar with other Level Measurements . . . . . . . . . . 6-15

APPENDIX 7
Checklists

TOC-2

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1

Checklists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2

Commissioning Procedure Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2

Measurement Validation at Operating Conditions

Procedure Checklist. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Section 1 Introduction

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-1

INTRODUCTION This document describes some of the best practices learned during the

installation of thousands of Rosemount process radar level transmitters in
refining applications. However, it is not a complete set of instructions; for more
detailed information refer to the respective product manual:

• Rosemount 5300 Series Reference Manual (Document No.
00809-0100-4530)

• Rosemount 5400 Series Reference Manual (Document No.
00809-0100-4026)

• Rosemount 5600 Series Reference Manual (Document No.
00809-0100-4024), and

• Rosemount 9901 Reference Manual (Document No.
00809-0100-4601).

Local restrictions, regulations, or best practices may also apply and should be
taken into consideration.

This best practices guide focuses on continuous level and interface
measurement applications used in refinery chambers. It also, where
appropriate, covers best practices for measurements in tanks and pipes.

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Rosemount Radar Level Transmitters

Reference Manual

00809-0200-4530, Rev AB

September 2009

1-2

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Section 2 Installation Considerations

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-2

Installation Considerations . . . . . . . . . . . . . . . . . . . . . . . . page 2-2

Chambers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-2

Pipes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-10

Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-12

SAFETY MESSAGES Procedures and instructions in this section may require special precautions to

ensure the safety of the personnel performing the operations. Information that
raises potential safety issues is indicated by a warning symbol ( ). Please
refer to the following safety messages before performing an operation
preceded by this symbol.

Explosions could result in death or serious injury.

Verify that the operating environment of the gauge is consistent with the appropriate
hazardous locations certifications.

Before connecting a HART
sure the instruments in the loop are installed in accordance with intrinsically safe or
non-incendive field wiring practices.

Do not remove the gauge cover in explosive atmospheres when the circuit is alive.

Failure to follow safe installation and servicing guidelines could result in death or
serious injury.

Make sure only qualified personnel perform the installation.

Use the equipment only as specified in this manual. Failure to do so may impair the
protection provided by the equipment.

Do not perform any service other than those contained in this manual unless you are
qualified.

High voltage that may be present on leads could cause electrical shock.

Avoid contact with leads and terminals.

Make sure the main power to the transmitter is off and the lines to any other external
power source are disconnected or not powered while wiring the gauge.

Probes covered with plastic and/or with plastic discs may generate an ignition-capable
level of electrostatic charge under certain extreme conditions. Therefore, when the
probe is used in a potentially explosive atmosphere, appropriate measures must be
taken to prevent electrostatic discharge.

®

-based communicator in an explosive atmosphere, make

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Reference Manual

Error

Error

Error

Error

Effective
measuring
range

00809-0200-4530, Rev AB

Rosemount Radar Level Transmitters

September 2009

INTRODUCTION In addition to selecting the appropriate radar level transmitter, mechanical

installation is one of the most critical steps of the commissioning procedure.
When done correctly, the subsequent transmitter configuration will be
considerably simplified.

Because of the wide usage and application in the refining industry, this
section provides a framework for chamber installations. The basics of pipe
and tank installation are also covered.

INSTALLATION CONSIDERATIONS

Chambers

Figure 2-1. Effective measuring
range and possible error
sources

Chambers - also known as bridles, side-pipes, bypass-pipes, and cages - are
typically used because:

• External mounting with valves allows for servicing of the level device,
even in pressurized tanks that are in continuous operation for many
years

• They allow for radar measurement in tanks or regions with
side-connections only, such as towers

• They provide a calmer surface in case of turbulence, boiling, or other
conditions that upset the product

However, chambers also have some disadvantages:

• Inlet pipes may clog and generate a discrepancy between the level
inside the chamber and the actual level in the tank

• The effective measuring range is limited to the region between the
upper and lower inlet pipes

2-2

Reference Manual

Level

Interface
Level

00809-0200-4530, Rev AB
September 2009

Figure 2-2. The Rosemount
5300 Series is an ideal choice
for continuous measurement of
level or interface in most
chamber applications

Rosemount Radar Level Transmitters

Generally, Guided Wave Radar (GWR) is favored in these applications since
non-contacting radar may be disturbed by the inlet-pipes. The Rosemount
5300 Series can be used in chambers to measure either level or interface
level.

Table 2-1. Measured variable
options

Transmitter Selection

The Rosemount 5300 Series can measure the level of oil, the interface of oil
and water, or other liquids with significant dielectric differences and a clear
interface between the two products.

For application guidelines, refer to ”Refining Applications” on page 3-2 or to
the Rosemount 5300 Series PDS (Document No. 00813-0100-4530).

There are two different transmitter versions, Rosemount 5301 and
Rosemount 5302. The required measurement variable will determine which
transmitter should be used:

Level only

Interface Level with

fully submerged

probe

Interface Level

Use the Rosemount 5301 (or alternatively Rosemount 5302 configured
for level only measurement)

The Rosemount 5301 can be used in this case. If there is an air gap, it

will generate an offset in the interface level measurement according to:

Interface Level offset = Air gap distance X ( 1 -

For example, an air gap of 4 in. (100 mm) with oil as upper product
(dc=2) generates a 1 in. (29 mm) positive interface level offset. In case
the air gap is constant, the interface level output can be compensated
by reducing the reference height with this offset.

In case there is an air-gap or the air gap is changing, the Rosemount
5302 should be used.

dielectric constant of upper product

1

)

2-3

Rosemount Radar Level Transmitters

Rosemount 5301

Level only

Rosemount 5301

Interface only with
fully submerged
probe (no air gap
thanks to venting)

Rosemount 5302

Interface (with or
without air gap)

Air gap

Flushing ring

Figure 2-3. Rosemount 5300
Series for Level and Interface
Measurement

Reference Manual

00809-0200-4530, Rev AB

September 2009

Figure 2-4. Rosemount 5300
Series transmitter with a flushing
ring

Flushing Connections and Vents

These options are recommended to remove the air-gap in interface
applications with fully submerged probes (5301):

• A separate flushing ring may be inserted between the 5300 flange and
cages that use ANSI or DIN flanges

2-4

• Proprietary flanges are available with an integrated vent option that are
used with 1½ in. (37.5 mm) NPT threaded probes

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

For further details and ordering information, see the Rosemount 5300 PDS
(Document No. 00813-0100-4530).

Venting may be needed to manipulate the level in the cage to verify the output
of the 5300, or to drain the cage. If this is the only purpose, a standard integral
cage vent is suitable, refer to the 9901 PDS (Document No.
00813-0100-4601).

Chamber Fabrication and Probe Selection

Dimensioning the chamber correctly and selecting the appropriate probe is
key to success in these applications. Either follow the recommendations
below and have the chamber manufactured accordingly, or purchase the
Rosemount 5300 Series transmitter bundled with the Rosemount 9901
chamber where Emerson has already incorporated these best practices.

The recommended chamber diameter is 3 in. (75 mm) or 4 in. (100 mm).
Chambers with a diameter less than 3 in. (75 mm) may cause problems with
build-up and it may also be difficult to center the probe. Chambers larger than
6 in. (150 mm) can be used, but provide no advantages for the radar
measurement.

With the Rosemount 5300 Series it is recommended that single probes in 3 in.
(75 mm) and 4 in. (100 mm) cages be used. Other probe types are more
susceptible to build-up and should not be used in this application.

(1)

The probe must not touch the chamber wall and should extend the full height
of the chamber, but does not need to touch the bottom of the chamber. Probe
type selection depends on the probe length:

Probe length is less than 3 ft (1 m): Use Single Rigid Probe and no
centering disk is needed.

(2)

Probe length is between 3 ft (1 m) and 10 ft (3 m): Use either Rigid Single
or Flexible Single Probe with the weight and centering disk. Rigid Single is
easier to clean and has smaller transition zones, while the Flexible Single
requires less head-space during installation and is less likely to be damaged.

Probe length is more than 10 ft (3 m): Use Flexible Single Probe with weight
and centering disk.

(1) The single probe creates a virtual coaxial probe with the chamber as the outer tube. The

extra gain provided by the twin and coaxial probes is not necessary; the electronics in the
5300 Series is very sensitive and is not a limiting factor.

(2) The transition zones, and the height of the weight, limit the usage of single flexible probes

shorter than 3 ft (1 m).

2-5

Rosemount Radar Level Transmitters

Make sure that the probe
does not come into
contact with the chamber
wall, e.g. by using a
centering disk.

A clearance
distance of 1 in.
(25 mm) between
the probe end and
the cage bottom is
recommended.

Upper Reference Point

Upper Transition Zone

Maximum
Measuring Range

Lower Transition Zone

Lower Reference Point

Figure 2-5. Improper and proper
probe positions

To avoid bending the probe (rigid probes), or twisting and coming into contact
with the chamber wall (flexible probes), a small clearance distance between
centering disk and chamber bottom is recommended. The clearance distance
of 1 in. (25 mm) is selected with a dome shaped chamber bottom in mind,
which may prevent the centering disk from reaching the bottom.

Reference Manual

00809-0200-4530, Rev AB

September 2009

Figure 2-6. Transition Zones and
Measuring Range

The location of the side-pipes and the effective measurement range is
determined by the mating tank connections. There are no diameter
requirements for the side-pipes, but build-up and clogging should be taken
into consideration. Ensure that the inlet pipes do not protrude into the
chamber because they may interfere with the radar measurement. Always
use the same material of construction for the chamber and the tank or
mechanical tensions can arise in the side-connections.

2-6

Reference Manual

A > Upper transition zone

B = Effectice Measuring
Range, determined by
mating tank connections

C > Lower transition
zone including weight
height (for flex probes)
and clearance distance

Single Rigid

Probe/chamber
diameter must
be 3 in. or 4 in.
(7.5 cm or 10 cm)

Use centering
disks for probes
> 3 ft (1 m)

Single Flex
for chambers
>= 3 ft (1 m)

Probe/chamber
diameter must
be 3 in. or 4 in.
(7.5 cm or 10 cm)

Always use a
centering disk

00809-0200-4530, Rev AB
September 2009

Table 2-2. Transition zones for
Rosemount 5300 Series

Rosemount Radar Level Transmitters

Rigid Single

Dielectric

Constant

(2)

Upper

Transition

Zone

(3)

Lower

Transition

Zone

(1) Rigid Single Lead probe without SST centering disk or with PTFE centering disk.
(2) The distance from the upper reference point where measurements have reduced accuracy, see

picture above.

(3) The distance from the lower reference point where measurements have reduced accuracy, see

picture above.

(4) Note that the weight length adds to non-measurable area and is not included in the diagram. See

section Dimensional Drawings in the 5300 Product Data Sheet (Document No. 00813-0100-4530).

(5) The measuring range for the PTFE covered Flexible Single Lead probe includes the weight when

measuring on a high dielectric media.

80 (water) 4.3 in. (11 cm) 4.3 in. (11 cm) 4.3 in. (11 cm)

2 (oil) 6.3 in. (16 cm) 6.3 in. (16 cm) 7.1 in. (18 cm)

80 (water) 2 in. (5 cm) 2 in. (5 cm) 0 in.

2 (oil) 2.8 in.

Rigid Single

(1)

Lead

(5)

(7 cm) 8 in. (20 cm) 2 in.

Transition zones, located at the very top and bottom of the probes, are
regions where measurement performance is reduced. Different factors affect
the size of the transition zones - probe type, centering disk or no centering
disk, and the material and media measured. See Table 2-2. The weight on the
flexible probes reduces the measurement range. Therefore, it is
recommended to dimension the cage (A, C) so it does not interfere with the
effective measurement range (B). The transition zones also limit the minimum
probe length.

Lead, with

metallic

centering disk

Flexible Single Lead

(4)(5)

(4)

(0 cm

(5 cm

(4)(5)

(4)

)

)

Figure 2-7. Measuring zones in
chambers

2-7

Rosemount Radar Level Transmitters

Probe length

23 in. (584 mm)

Displacer length

14 in. (356 mm)

LRV 0 in. (0 mm)

URV 14 in. (356 mm)

Tank Height

(Reference Gauge Height)

19 in. (483 mm)

An example using the guidelines for fabrication of cages

(see Table 2-2 on page 2-7 for transition zones)

Assuming level measurement of oil (worst-case); A > 6.3 in. (16 cm) and C >

9.8 in. (25 cm) for rigid single probe with a metallic centering disk, and A > 7.1
in. (18 cm) and C > 9.4 in. (24 cm) for single flexible with a standard weight.
There is a 2 in. (5 cm) clearance between the cage bottom and the end of the
probe included in the C- dimensions.

Existing Chambers

Retrofitting of existing chambers is very common, especially when replacing
old mechanical devices such as displacers. For further information, refer to
the Technical Note "Replacing Displacers with Guided Wave Radar"
(Document No. 00840-2200-4811).

Setting Range Values - Three Options

Chambers are mounted onto the tank to correspond with the desired
measurement and area of control. This is often a small portion of the overall
height.

Reference Manual

00809-0200-4530, Rev AB

September 2009

Figure 2-8. Setting range values,
Option 1 - Setting LRV to 0 in.
(0 mm) at the lower tap

For displacers, the output span corresponds to the displacer length, with
lower (LRV) and upper range values (URV) representing the bottom and top
of the displacer. In side-to-side chambers, this corresponds to
center-of-the-pipe connections to the vessel.

Option 1 - Setting LRV to 0 in. (0 mm) at the Lower Tap

The Tank Height should be set to the distance to the zero level point. In this
example, it is the lower side-pipe, located 19 in. (483 mm) below the
reference point. Output range values will equal the pipe connection heights
relative to the zero level point. LRV should be set at 0 in. (0 mm), the URV
should be set at 14 in. (356 mm), and the probe should be set to the correct
probe length.

2-8

Reference Manual

Displacer length

14 in. (356 mm)

Probe length

23 in. (584 mm)

URV 18 in.
(457 mm)

LRV 4 in.
(102 mm)

Tank Height

Reference Gauge Height)

23 in. (584 mm)

LRV 112 in. (2.8 m)

Gauge height
(Same as tank
height)
150 in. (3.75 m)

Tank bottom reference point

Displacer length
32 in. (0.8 m)

URV 144 in. (3.6 m)

00809-0200-4530, Rev AB
September 2009

Figure 2-9. Setting range values,
Option 2 - Matching displacer
output

Rosemount Radar Level Transmitters

Option 2 - Matching Displacer Output

The tank height (reference gauge height) and the probe length should be set
to the same value. The LRV is the distance from the bottom of the probe to
the lower tap. The URV is the LRV plus the distance to the upper tap. In this
example, Tank Height (Reference Gauge Height) equals the probe length of
23 in. (584 mm), the LRV is 4 in. (102 mm), and the URV is 18 in. (457 mm).

Figure 2-10. Setting range
values, Option 3 - Actual tank
level

Option 3 - Matching Actual Tank Level

For the level measurement to correspond to the actual level, the correct
gauge height needs to be entered. The LRV is the distance from the bottom of
the tank, or the common reference line, to the lower tank connection tap. For
the URV, add the tank connection distance, and the actual probe length needs
to be entered.

2-9

Rosemount Radar Level Transmitters

Example: Replacing a 32 in. (813 mm) displacer with a 41 in. (1041 mm)
probe. The gauge height is the distance from the top flange to the tank bottom
reference point. The probe length will be the actual probe length. The LRV
setting will be the height of the lower tank connection relative to the tank
bottom.

Insulation

The chamber should always be insulated in hot application to prevent
personal injuries and reduce the amount of energy needed for heating. It is
often an advantage, and sometimes even required, for the radar
measurement:

• In hot applications, insulation will reduce the amount of condensation,
since it prevents the upper part of the chamber from becoming a cold
spot

• Insulation prevents the product from solidifying inside the chamber, and
clogging the inlet-pipes

Figure 2-11. Always use
insulation in hot applications

Reference Manual

00809-0200-4530, Rev AB

September 2009

Pipes Stilling wells or pipes are used in many applications and many different types

of tanks and vessels. The reasons for having the pipes differ, but are typically
beneficial from an application standpoint, since pipes will offer a calmer,
cleaner surface and eliminate issues with disturbing obstacles.

Both Guided Wave and non-contacting Radar perform well in pipes:

• Use the 5300 Series in shorter pipes (less than 10 ft [3 m]) or if
interface measurement is required

• Use the 5400 Series in longer pipes (over 10 ft [3 m]) or if there is a risk
for build-up on a GWR probe

• The 5300 Series cannot be isolated; use the Rosemount 5402 with a
full-port ball valve for applications that cannot be taken out of operation
for service

2-10

Reference Manual

Rosemount
5400 Series

Rosemount
5300 Series

Max. 0.2 in.
(5 mm)

(N)

00809-0200-4530, Rev AB
September 2009

Figure 2-12. Pipes in a tank

Rosemount Radar Level Transmitters

Figure 2-13. 5400 in pipes and
slot size

With the 5400 Series, ensure that the cone antenna or process seal antenna
is used in the pipes, and that the size of the holes or slots is limited in size.
See Figure 2-14 on page 2-12. Holes should be drilled on one side of the
pipe. The gap between the cone-antenna and the pipe should not be larger
than 2 in. (5 mm). If needed, buy an oversized cone and cut on site. With
non-contacting radar in pipe installations with low dielectric fluids, install a
deflection plate with an approximate angle of 45° at the bottom of the pipe.
Failure to follow these requirements may affect the reliability of the level
measurement.

2-11

Rosemount Radar Level Transmitters

Min. 6 in. (150 mm)

Max. Ø: D/10. (e.g. 4" pipe
should have max 0.4" holes)

Figure 2-14. Rosemount 5400
Series recommended hole sizes
for pipe installations

For the 5300 Series the installation considerations are virtually identical with
chambers, as covered in the previous section of this document.

Reference Manual

00809-0200-4530, Rev AB

September 2009

For more details, refer to the Technical Note "Guidelines for Choosing and
Installing Radar in Stilling Wells and bypass pipes" (Document No.
00840-0200-4024).

Tanks Recommended Mounting Position

When finding an appropriate mounting position for the transmitter, the
conditions of the tank must be carefully considered.

For the Rosemount 5300 Series:

• Do not mount close to inlet pipes and ensure that the probe does not
come in contact with the nozzle (X)

• If there is a chance that the probe may come in contact with the tank
wall, nozzle or other tank obstructions, the coaxial probe is the only
recommended choice. Minimum clearance is given in Table 2-3 on
page 2-13

• Generally, the Rosemount 5400 Series is recommended in tanks with
agitators. If the probe sways due to turbulent conditions, the probe
should be anchored to the tank bottom (Y). Refer to the 5300 Series
Reference Manual (00809-0100-4530) for anchoring options. Also note
that violent fluid movements that cause high sideway forces may break
rigid probes

2-12

Reference Manual

XY

00809-0200-4530, Rev AB
September 2009

Figure 2-15. Tank with agitator

Rosemount Radar Level Transmitters

Table 2-3. Minimal clearances
of probes

Min.

clearance to

tank wall or
obstruction

Coaxial

0 in. (0 cm)

Rigid Twin

Lead

4 in. (10 cm) 4 in. (10 cm)

Flexible Twin

Lead

Rigid Single

Lead

4 in. (10 cm) in
the case of
smooth metallic
wall.
20 in. (50 cm) in
the case of
disturbing
objects, rugged
metallic or
concrete/plastic
wall.

Flexible Single

Lead

4 in. (10 cm) in
the case of
smooth metallic
wall.
20 in. (50 cm) in
the case of
disturbing
objects, rugged
metallic or
concrete/plastic
wall.

The Rosemount 5400 Series should be installed in locations with a clear and
unobstructed view of the level surface (A) for optimum performance:

• Filling inlets creating turbulence (B), and stationary metallic objects with
horizontal surfaces (C) should be kept at a distance, outside the signal
beam. See the 5400 PDS for more information (Document No.
00813-0100-4026)

• Agitators with large horizontal blades may reduce the performance of
the transmitter, so install the transmitter in a location where this effect is
minimized. Vertical or slanted blades are often invisible to radar, but
create turbulence (D)

• Do not install the transmitter in the center of the tank (E)

• Because of circular polarization, there is no clearance distance
requirement from the tank wall if it is flat and free from obstructions,
such as heating coils and ladders (F). Usually, the optimal location is
1/3 of the radius from the tank wall

2-13

Rosemount Radar Level Transmitters

DAEBFC

Figure 2-16. Proper and
improper locations for the
Rosemount 5400 Series
transmitter

Nozzle Considerations

Reference Manual

00809-0200-4530, Rev AB

September 2009

Depending on the selection of transmitter model and probe/antenna, special
considerations may have to be taken because of the nozzle.

Rosemount 5300 Series

The coaxial probe signal is unaffected by the nozzle.

The single and twin probes have some nozzle restrictions, e.g. avoid using
nozzles with reducers, and nozzles that are too tall or too narrow.

2-14

Reference Manual

Avoid nozzles with reducer
(unless using Coaxial probe)

H

D

UNZ

00809-0200-4530, Rev AB
September 2009

Figure 2-17. Mounting in nozzles

Rosemount Radar Level Transmitters

Table 2-4. Nozzle
considerations

Recommended
Nozzle Diameter (D)

Minimum Nozzle
Diameter (D)

Maximum Nozzle
Height (H)

(1) An Upper Null Zone setup may be required to mask the nozzle, which may reduce the measuring

(2) When using single flexible probes in tall nozzles, it is recommended to use the Long Stud (LS).

(1)

range.

Rosemount 5400 Series

5402 with Cone Antenna

The antenna can be used in nozzles equal to or larger than 2 in. (50 mm). It
can be recessed in smooth nozzles up to 6 ft (2 m). If the inside of the nozzle
contains disturbing objects, use the extended cone (l).

Single (Rigid/Flexible) Coaxial Twin (Rigid/Flexible)

4-6 in. (100-150 mm)

2 in. (50 mm)

4 in. + Nozzle Diameter

> Probe Diameter

> Probe Diameter 2 in. (50 mm)

N/A

4-6 in. (100-150 mm)

4 in. + Nozzle

Diameter

(2)

2-15

Rosemount Radar Level Transmitters

(I)

Smooth nozzle

Bad weldings

Spray nozzle

(J)

(K) Bad welding

(L) 0.4 in. (10 mm) or more

Figure 2-18. Rosemount 5402
with Cone Antenna

5402 with Process Seal Antenna

The antenna can be used in 2, 3, and 4 in. (50, 75, and 100 mm) nozzles up
to 6 ft (2 m) tall (J), but disturbing objects inside the nozzle (K) may impact the
measurement, and should be avoided. The flange on the tank should have a
flat or raised face, but other tank flanges may be possible. Consult your local
Emerson Process Management representative for assistance.

Reference Manual

00809-0200-4530, Rev AB

September 2009

Figure 2-19. Rosemount 5402
with Process Seal Antenna

Figure 2-20. Rosemount 5401
with Cone Antenna

5401 with Cone Antenna

This antenna can be used in tanks with nozzles equal to or larger than 4 in.
(100 mm) and can extend 0.4 in. (10 mm) or more below the nozzle (L). If
required, use the extended cone solution.

2-16

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Process Isolation for Service

It is recommended that the Rosemount 5400 Series use a full-port ball valve
in applications that cannot be taken out of operation for service.

The 5402 is required, and the preferred choice is the Process Seal Antenna,
since it does not require a spool piece. The cone antenna can also be used,
but a spool piece will be needed.

Ensure there is no edge between the ball valve and the nozzle/pipe. The
inside should be smooth.

The 5300 Series cannot be used with valves because of the protrusion of the
probe into the tank. If process isolation is needed with the 5300 Series, a
chamber is recommended.

Probe and Antenna Selection

Besides mounting position, nozzle considerations, and process isolation,
there are other factors that need to be taken into consideration when selecting
the probe or antenna:

• Single probes and cone-antennas are recommended in most
applications. Always use the largest possible antenna

• In case of turbulent surface conditions or foam, consider using the
coaxial probe with GWR. When using non-contacting radar, consider
using a stilling well

• The coaxial and twin lead probes have longer measuring ranges than
the single probes, but are more sensitive to build-up and coating

Table 2-5. Factors of probe
selection

Coaxial Twin Lead Single Lead

Maximum Viscosity

(1)

500 cP

Coating/Build-up

Coating not recommended Thin coating allowed, but no bridging Coating allowed

(1) About the same viscosity as motor oil SAE30 at room temperature.
(2) About the same viscosity as motor oil SAE70 at room temperature.
(3) About the same viscosity as molasses at room temperature.

1500 cP

(2)

8000 cP

(3)

Always ensure that the wetted materials are compatible with the process and
that the probe/antenna will withstand the application's temperature and
pressure range.

For more information, refer to the Level Selection Guide (Document No.
00803-0100-6112).

2-17

Rosemount Radar Level Transmitters

Reference Manual

00809-0200-4530, Rev AB

September 2009

2-18

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Section 3 Refining Applications

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-1

Refining Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-2

Chambers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-2

Pipes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-9

Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-10

Applications to limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-14

SAFETY MESSAGES Procedures and instructions in this section may require special precautions to

ensure the safety of the personnel performing the operations. Information that
raises potential safety issues is indicated by a warning symbol ( ). Please
refer to the following safety messages before performing an operation
preceded by this symbol.

Explosions could result in death or serious injury.

Verify that the operating environment of the gauge is consistent with the appropriate
hazardous locations certifications.

Before connecting a HART
sure the instruments in the loop are installed in accordance with intrinsically safe or
non-incendive field wiring practices.

Do not remove the gauge cover in explosive atmospheres when the circuit is alive.

Failure to follow safe installation and servicing guidelines could result in death or
serious injury.

Make sure only qualified personnel perform the installation.

Use the equipment only as specified in this manual. Failure to do so may impair the
protection provided by the equipment.

Do not perform any service other than those contained in this manual unless you are
qualified.

High voltage that may be present on leads could cause electrical shock.

Avoid contact with leads and terminals.

Make sure the main power to the transmitter is off and the lines to any other external
power source are disconnected or not powered while wiring the gauge.

Probes covered with plastic and/or with plastic discs may generate an ignition-capable
level of electrostatic charge under certain extreme conditions. Therefore, when the
probe is used in a potentially explosive atmosphere, appropriate measures must be
taken to prevent electrostatic discharge.

®

-based communicator in an explosive atmosphere, make

www.rosemount.com

Reference Manual

Level

Rosemount 5301

Rosemount 5301

00809-0200-4530, Rev AB

Rosemount Radar Level Transmitters

September 2009

INTRODUCTION This section covers refining applications in chambers, pipes, and tanks

regarding pressure, temperature and measurement.

Besides the list of typical applications, application characteristics, and best
practices suggested here, there is also a description on the applications to
avoid at the end of the section.

REFINING APPLICATIONS

Chambers

Figure 3-1. Tower bridles and
reboiler application with
Rosemount 5301 transmitters

High temperature at low to moderate pressure ­Level Measurement

Typical Applications

• Distillation Towers (Lower Portions)

• Reflux/Reboilers

• Accumulator

3-2

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Application characteristics

• Boiling fluid results in a low signal return for the radar, especially
hydrocarbon products, e.g. Oils and Diesel in crude oil distillation
towers

• The product may be very viscous and cause heavy build-up in the
chamber

• Heavy vapors may result in build-up on the probe

Best Practices

• A Rosemount 5301 with a single lead probe, option code "4A" or "5A" is
recommended. A centering disk should be included, if needed

• Temperature considerations:

- The high-temperature high-pressure (HTHP) tank seal, option code
'H' should be used. It has a maximum temperature of 750 °F (400 °C)

- Use metallic centering disks, option code 'Sx'

• In applications with very low signal strength, it is recommended to
activate the transmitter firmware function Probe End Projection (PEP).
For more information, refer to Rosemount 5300 Series Reference
Manual (Document No. 00809-0100-4530)

• Insulate the chamber to reduce the amount of condensation

NOTE

In some processes, e.g. vacuum residue towers, the fluid may be too viscous
for practical use in a chamber. For these cases, a DP with flushing
connections is recommended.

If the temperature is lower than 300 °F (150 °C), the standard tank seal may
be used instead of the HTHP option. For example, this may apply to the upper
portion of a distillation tower. See Section 4 "Commissioning" on page 4-2.

3-3

Rosemount Radar Level Transmitters

Rosemount 5301

High Temperature and High Pressure ­Level Measurement

Typical Applications

• Boiler feedwater systems

Figure 3-2. Boiler feedwater
system

Reference Manual

00809-0200-4530, Rev AB

September 2009

Table 3-1. Properties of water
and saturated steam

Application characteristics

• Boiling water with saturated steam vapors

• Heavy water condensation

• Water and saturated steam have certain properties, see Table 3-1

- The returned signal from the surface becomes weaker as water
temperature increases.

- If not taken into account, the saturated steam alters the propagation
velocity of the radar signal and generates an error in the level reading
proportional to the measured distance. Increased pressure and
temperature will affect the error in measured distance.

Temperature

°F (°C)

100 (38) 0.95 74 1.001 0.0

200 (93) 11.5 57 1.005 0.2

300 (149) 67 44 1.022 1.1

400 (204) 247 34 1.069 3.4

500 (260) 680 25 1.180 8.6

600 (315) 1543 18 1.461 20.9

Pressure

psia

DC of liquid

DC of saturated

steam

Error in distance

(%) if uncorrected

3-4

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Best Practices

• It is recommended that the Rosemount 5301 use a single lead probe,
option-code "4A" or "5A", and a centering disk if needed

Temperature considerations:

- Use the high-temperature high-pressure (HTHP) tank seal, option
code 'H', with maximum P/T 2940 psig at 752 °F (203 bar at 400 °C)

- Use metallic centering disks, option-code 'Sx'

• Insulate the chamber to reduce condensation

• When commissioning the transmitter, the specific properties of water
and saturated steam must be taken into account:

Configure the transmitter when the tank is in operation, otherwise the
signal returned from the surface will be too high and the transmitter will
not be configured correctly.

Rosemount Radar Master (RRM) can be used to compensate for the
error induced by the saturated steam:

Figure 3-3. Vapor Dielectric
Constant Calculator (LT-01)

Setup > Tank > Environment > Activate Advanced Mode > Vapor
Dielectric Constant Calculator

NOTE

The saturated steam compensation is fixed and will only adjust the level
reading at specified conditions. This means that the transmitter shows a
correct level reading during operation, but not during startup and shutdown
when these conditions are not fulfilled. See Table 3-2 on page 3-6.

3-5

Rosemount Radar Level Transmitters

5301

5302

5302

5301

Table 3-2. Level Reading Errors
during shutdown, with fixed
saturated water steam
correction activated

Entered Vapor

DC

1.001 0 in. (0 mm) 0 in. (0 mm) 0 in. (0 mm)

1.022 0.2 in. (4 mm) 0.3 in. (8 mm) 0 in. (0 mm)

1.180 1.3 in. (33 mm) 2.6 in. (65 mm) 0 in. (0 mm)

Error in reading, when actual Vapor DC is 1

(corresponding to water at room temperature)

Surface at 15 in (380 mm)

from flange

High Temperature and High Pressure ­Level and Interface Measurement

Typical Applications

• Separators, such as cold HP, hot LP in the hydrotreater

• Coalescers

Reference Manual

00809-0200-4530, Rev AB

September 2009

Offset in reading,

if Vapor DC is

configured

correctly

Surface at 30 in. (760

mm) from flange

Figure 3-4. Separators with
Rosemount 5300 Series
transmitters

Application characteristics

• There may be a fairly large emulsion between the products, which may
make the interface indistinct

• Vapors may generate build-up

3-6

Reference Manual

Level

Rosemount 5301

5301

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Best Practices

• Use the Rosemount 5301 with a separate flushing ring or flange and
the integrated venting option. Alternatively, if there is an air gap, use
the 5302

• Refer to the 5300 Product Data Sheet (Document No.
00813-0100-4530) to ensure that the conditions for interface
measurement are fulfilled, especially with respect to the emulsion layer

• For chambers, it is recommended that the single lead probe,
option-code "4A" or "5A" is used along with a centering disk, if needed

• Temperature and pressure considerations:

- Use the high-temperature high-pressure (HTHP) tank seal, option
code 'H', maximum P/T 2940 psig at 752 °F (203 bar at 400 °C).

- Use metallic centering disks, option-code 'Sx'

• Because of the emulsion layer, Interface Threshold may need manual
adjustment

Standard Temperature and Standard Pressure ­Level Measurement

Figure 3-5. Distillation tower and
separator with Rosemount 5300
Series transmitter

Typical Applications

• Distillation Towers (Upper portions)

• Separators

• Knock-out drums

• Accumulators/Feed tanks

3-7

Rosemount Radar Level Transmitters

5302

Best Practices

• It is recommended that the Rosemount 5301 with a single lead probe,
option-code "4A" or "5A" is used along with a centering disk, if needed

• Use the standard tank seal, option code 'S', with pressure and
temperature range 15 psig (-1bar) to 580 psig (40 bar) @ 302 °F (150
°C)

• Besides the metallic centering disk, PTFE may also be used, option
code 'Px'

Standard Temperature and Standard Pressure ­Interface Measurement

Typical Applications

• Accumulators

• Settling Tanks

• Skimmers

• Separators

Best Practices

• Use the Rosemount 5301 with a separate flushing ring or flange and
integrated venting option. Alternatively, if there is an air gap, use the
5302

• For chambers, it is recommended that the single lead probe, option
code "4A" or "5A" is used along with a centering disk, if needed

• Use the standard tank seal, option code 'S', with pressure and
temperature range 15 psig (-1bar) to 580 psig (40 bar) @ 302 °F (150
°C)

• Besides the metallic centering disk, PTFE may also be used, option
code 'Px'

Reference Manual

00809-0200-4530, Rev AB

September 2009

Figure 3-6. Interface
measurement in a separator
using a Rosemount 5302
transmitter

3-8

Reference Manual

Wash
Water

Wash
Water

Chemicals

Crude Oil

Oil

Rosemount 5302

00809-0200-4530, Rev AB
September 2009

Pipes Desalters

Figure 3-7. Desalter with a
Rosemount 5302 transmitter

Rosemount Radar Level Transmitters

Application characteristics

• The crude oil is viscous and dirty with solids and water content

• The interface is indistinct, because of a large emulsion layer between
the two products

Best Practices

• Use the Rosemount 5302 with multivariable output for measurement of
both level and interface

• It is required to insert the probe in a 4 in. (100 mm) stilling-well to
reduce the emulsion layer. Drill as many holes as possible, since these
effectively set the resolution for the interface measurement

• It is recommended to use a single lead probe, option code "4A" or "5A",
with a centering disk, option-code 'Px' or 'Sx'

• Use the standard tank seal, option code 'S', with pressure and
temperature range -15 psig (-1 bar) to 580 psig (40 bar) @ 302 ºF (150
ºC)

• Ensure that the electronics housing does not get warmer than the
specified temperature limit; if needed, use the high-temperature
high-pressure (HTHP) tank seal, option code ’H’, to move the
transmitter housing further away from the process

• Besides the metallic centering disk, PTFE may also be used, option
code 'Px'

• Because of the emulsion layer, it is likely that the Interface Threshold
will need manual adjustment

Liquefied Gases

Typical Applications

• Small containers of LNG, LPG

3-9

Rosemount Radar Level Transmitters

Application Characteristics

• Liquefied gases have a very low dielectric constant and a very small
signal return

• Boiling fluid reduces the signal return additionally

Best Practices

• For non-inventory measurements, the Rosemount 5402 with cone- or
process-seal antenna can be used

• A 2-4 in. (50-100 mm) stilling well is required to calm the surface

• A full-port ball-valve should be used for process isolation

Tanks Ammonia

Application characteristics

• Anhydrous ammonia has heavy vapors that attenuate the signal

Best Practices

• Use 5301 with any of the probe-types

• Ensure the wetted materials are compatible with the process. For
example, many users consider Viton
incompatible with this process. The High Pressure tank seal, option
code 'P', can be used if a solution without O-rings is preferred.

• For further information, see Technical Note (Document No.
00840-0100-4811).

Reference Manual

00809-0200-4530, Rev AB

September 2009

®

and Buna-N® O-rings to be

Solids

Typical Applications

• Coke Bins

• Spent Catalyst Hopper

• Sulfur pits

3-10

Reference Manual

Rosemount 5402 Process Seal
with nozzle insulation

Rosemount 5600 and
5303 with dust cover

00809-0200-4530, Rev AB
September 2009

Figure 3-8. A sulfur pit with a
Rosemount 5402 transmitter
(above)

Catalyst Hopper with a
Rosemount 5600 transmitter
(below)

Rosemount Radar Level Transmitters

Application characteristics

• The surface of solid materials is rarely flat or horizontal, and the angle
of repose, or surface inclination, will change as the vessel fills and
empties

• The dielectric value of most solids is fairly low. For radar, this is a key
indicator of the amount of signal that will be reflected back to the gauge

• There is often a lot of dust during the fill cycle

• Heavier materials can create a pull force that can break cables. This
can be an issue in vessels taller than 50 ft (15 m), and should be taken
into account to guard against this

Best Practices

• Sulfur pits: use Rosemount 5402 with process-seal antenna. Purge,
insulate, heat-trace the nozzle or similar to reduce the amount of
build-up

• Spent catalyst hopper
under 60 ft (18 m): use Rosemount 5303 with long-stud and standard
6A-probe
over 60 ft (18 m): use Rosemount 5601 parabolic with dust-cover

• Coke bins: use Rosemount 5600 parabolic with dust-cover

3-11

Rosemount Radar Level Transmitters

Rosemount 5402

Rosemount 5400 Series

Storage Tanks

Typical Applications

• Chemical storage - acids, caustics, fuels, ..

• Waste water

• Crude oil buffer storage

Figure 3-9. Chemical storage

Reference Manual

00809-0200-4530, Rev AB

September 2009

Figure 3-10. Tank with agitator
using Rosemount 5400 Series
transmitters

Best Practices

• Use Rosemount 5402 with Cone antenna

• Consider material compatibility

Tanks with agitators

Typical Applications

• Mixing tanks - acids, catalysts

• Blending tanks

• Reactors

3-12

Reference Manual

00809-0200-4530, Rev AB
September 2009

Figure 3-11. Compressor tank

Rosemount Radar Level Transmitters

Application characteristics

• May be corrosive, vapors, turbulence, foam

Best Practices

• Typically 5400 is used

Compressor tanks

Application characteristics

• Small tank containing oil

• The tank may be too small to fit a chamber - direct connection is more
likely

Best Practices

• Rosemount 5301 standard single is recommended

Tanks with very rapid level changes

Typical Applications

• Blowdown drum

3-13

Rosemount Radar Level Transmitters

Figure 3-12. Blowdown drum
with a Rosemount 5600 Series
transmitter

Reference Manual

00809-0200-4530, Rev AB

September 2009

Application characteristics

• Tank may fill up very rapidly, for example because of upset in the
process

Best Practices

• Use Rosemount 5600

Applications to limit Generally, GWR is not suitable for extremely viscous products where fluid flow

is minimal. If GWR is used in a chamber with very viscous fluids, the chamber
should be heat traced and insulated to ensure fluidity. A vacuum residue unit
is an example of this type of application. Coke drums, where the fluid
hardens, is not a suitable application for GWR. Applications where heavy
coating is likely, such as asphalt, are more suitable for non-contacting radar.

Very small vessels (less than 18 inches [450 mm]) may cause measurements
that are more within the transition zones than the active measurement region.
In addition, if the fluid has a low dielectric constant and is hot, and/or
turbulent, then threshold settings may require more care. Contact your local
Emerson Process Management representative for assistance.

3-14

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September 2009

Rosemount Radar Level Transmitters

Section 4 Commissioning

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4-1

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4-1

Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4-2

Trim Near Zone (5300 Series only) . . . . . . . . . . . . . . . . . . page 4-2

Store Backup and Verification Files . . . . . . . . . . . . . . . . . page 4-3

On the Bench Test (optional) . . . . . . . . . . . . . . . . . . . . . . . page 4-3

SAFETY MESSAGES Procedures and instructions in this section may require special precautions to

ensure the safety of the personnel performing the operations. Information that
raises potential safety issues is indicated by a warning symbol ( ). Please
refer to the following safety messages before performing an operation
preceded by this symbol.

Explosions could result in death or serious injury.

Verify that the operating environment of the gauge is consistent with the appropriate
hazardous locations certifications.

Before connecting a HART
sure the instruments in the loop are installed in accordance with intrinsically safe or
non-incendive field wiring practices.

Do not remove the gauge cover in explosive atmospheres when the circuit is alive.

Failure to follow safe installation and servicing guidelines could result in death or
serious injury.

Make sure only qualified personnel perform the installation.

Use the equipment only as specified in this manual. Failure to do so may impair the
protection provided by the equipment.

Do not perform any service other than those contained in this manual unless you are
qualified.

High voltage that may be present on leads could cause electrical shock.

Avoid contact with leads and terminals.

Make sure the main power to the transmitter is off and the lines to any other external
power source are disconnected or not powered while wiring the gauge.

Probes covered with plastic and/or with plastic discs may generate an ignition-capable
level of electrostatic charge under certain extreme conditions. Therefore, when the
probe is used in a potentially explosive atmosphere, appropriate measures must be
taken to prevent electrostatic discharge.

®

-based communicator in an explosive atmosphere, make

www.rosemount.com

Reference Manual

00809-0200-4530, Rev AB

Rosemount Radar Level Transmitters

September 2009

INTRODUCTION This section is a brief outline of commissioning, and does not provide

comprehensive information on the whole procedure.

For the commissioning process, follow the steps of the product-related Quick
Installation Guides. For your convenience, a checklist is provided in the
Appendix of this Manual Supplement.

COMMISSIONING The transmitter installation should be carried out as described in the Quick

Installation Guide that is enclosed with every transmitter. Even though the
transmitter may be installed on the bench, it must be configured to the actual
process conditions.

For a 5300 Series transmitter, do not bend the probe during any part of the
installation. It may be necessary to shorten the probe, mount a centering disk,
or anchor the probe during the mechanical installation. For more information,
see the Reference Manual (00809-0100-4530).

Beside these required steps, the procedures below are recommended as best
practices.

Trim Near Zone (5300 Series only)

Figure 4-1. Advanced
Configuration - [LT-01]

The Rosemount 5300 Series is equipped with a firmware functionality that
minimizes the Upper Transition Zone based on actual mounting conditions.
Best practice in refining applications, where short chambers are often used,
this function is advised.

To activate this function, ensure that the tank or chamber is empty, and that
the (upper) product is not closer than 40 in. (1 m). Then execute the Trim
Near Zone command.

Rosemount Radar Master > Advanced > Near Zone > Trim Near Zone

4-2

For detailed information on the Trim Near Zone function, refer to 5300 Series
Reference Manual (Document No. 00809-0100-4530).

Reference Manual

Water

Distance

Amplitude

How it would look with
actual product (oil) in tank

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Store Backup and Verification Files

On the Bench Test (optional)

As the last step of the commissioning procedure, it is recommended that both
the transmitter settings and the echo curve be stored. For example, these can
be used for subsequent transmitter verification or troubleshooting.

Rosemount Radar Master > Device > Backup Config to file

Rosemount Radar Master > Tools > Echo Curve > Record

Sometimes the actual process is not available and the transmitter is
pre-commissioned on the bench. In this case, the level is often simulated
using metal-plates, water, or other targets.

Although, these tests provide a basic verification of the transmitter, they do
not verify that the transmitter functions properly at the actual process
conditions.

Bench tests complement verification tests, but do not replace them. The
instructions in Section 5 ”Measurement Validation at Operating Conditions”
should be followed and the bench test is considered optional.

One of the largest differences between the simulated level and the actual
level during operating conditions is the amplitude of the surface peak. For
example, in a 4 in. (100 mm) chamber using the 5300 Series transmitter and a
single probe, the peak of water can be 10,000 mV, while oil would be 2,000
mV under the same conditions.

Never set the thresholds according to simulated level values since there
is a major risk that the thresholds are set too high.

Figure 4-2. The difference
between the amplitude of
surface peaks in the case of
simulated and actual liquid
levels

Generally, it is advised to accept the automatic settings. If it is necessary to
adjust the thresholds, do the adjustments the first time the process is started
at actual operating conditions.

Normally, the thresholds do not require any adjustments on the custom
settings.

4-3

Rosemount Radar Level Transmitters

Example

A 5300 Series transmitter mounted in a chamber can be verified by
connecting flexible transparent tubing to the bottom drain, ensuring that there
are no crimps or folds in the bend to impede the flow.

The inlet-pipes are sealed by closing the valves, and filling the chamber with
water using the upper vent hole. The level is varied between the 4-20 mA
set-points to verify that the basic transmitter settings have been configured
correctly.

Once the chamber is mounted on the actual tank and the process is started, a
complete verification is carried out according to Section 5, ”Measurement
Validation at Operating Conditions”.

Figure 4-3. Verification of
transmitter measurement in
bridle application using tubing

Reference Manual

00809-0200-4530, Rev AB

September 2009

Fill water here

Measure

here

Closed

Valves

4-4

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00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Section 5 Measurement Validation at

Operating Conditions

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 5-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 5-2

Step 1: Verify the Correctness of Level Reading . . . . . . . page 5-2

Step 2: Analog Output Signal Validation . . . . . . . . . . . . . page 5-3

Step 3: Echo-Curve Verification at Operating Conditions page 5-4

Step 4: Transmitter Diagnostics Review . . . . . . . . . . . . . page 5-4

Step 5: Monitor Level while Emptying . . . . . . . . . . . . . . . page 5-5

Step 6: Echo-Curve Verification with Empty Tank . . . . . . page 5-6

Step 7: Monitor Level while Filling . . . . . . . . . . . . . . . . . . page 5-6

SAFETY MESSAGES Procedures and instructions in this section may require special precautions to

ensure the safety of the personnel performing the operations. Information that
raises potential safety issues is indicated by a warning symbol ( ). Please
refer to the following safety messages before performing an operation
preceded by this symbol.

Explosions could result in death or serious injury.

Verify that the operating environment of the gauge is consistent with the appropriate
hazardous locations certifications.

Before connecting a HART
sure the instruments in the loop are installed in accordance with intrinsically safe or
non-incendive field wiring practices.

Do not remove the gauge cover in explosive atmospheres when the circuit is alive.

Failure to follow safe installation and servicing guidelines could result in death or
serious injury.

Make sure only qualified personnel perform the installation.

Use the equipment only as specified in this manual. Failure to do so may impair the
protection provided by the equipment.

Do not perform any service other than those contained in this manual unless you are
qualified.

High voltage that may be present on leads could cause electrical shock.

Avoid contact with leads and terminals.

Make sure the main power to the transmitter is off and the lines to any other external
power source are disconnected or not powered while wiring
the gauge.

Probes covered with plastic and/or with plastic discs may generate an ignition-capable
level of electrostatic charge under certain extreme conditions. Therefore, when the
probe is used in a potentially explosive atmosphere, appropriate measures must be
taken to prevent electrostatic discharge.

®

-based communicator in an explosive atmosphere, make

www.rosemount.com

Reference Manual

00809-0200-4530, Rev AB

Rosemount Radar Level Transmitters

September 2009

INTRODUCTION In this section, the steps of measurement validation at operating conditions

are described.

For measurement validation, the actual liquid must be used to ensure the
accuracy of the measurement data.

MEASUREMENT VALIDATION AT OPERATING CONDITIONS

Step 1: Verify the Correctness of Level Reading

Once a Rosemount Radar transmitter has been installed and configured, it
will continuously deliver measurements with a minimum of maintenance. The
electronics are self-adjusting, so no re-calibration is needed.

This sample procedure is intended to be a part of the startup process, or as a
re-occurring functional check, to validate the integrity of the transmitter during
actual operating conditions. If the verification fails, refer to Section 6,
”Troubleshooting Procedures”.

All of the steps in this sample verification procedure are independent and
although it is not recommended, single steps may be omitted.

Before you start the verification procedure, ensure that proper actions have
been taken so as not to affect the safety or performance of the process.

A checklist is provided in the Appendix for this stage of the process for your
convenience.

At normal operating conditions, compare the transmitter level, or interface
reading, with an independent measurement. Unfortunately, it often happens
that two independent measurements will not match up perfectly, but check the
sanity and the acceptable deviation.

The independent measurement can be done using a number of different
complementary devices, ranging from sight-glasses and hand-dipping to
redundant differential-pressure and displacer.

Figure 5-1. The verification of
measurement data using a
sight-glass

5-2

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September 2009

Rosemount Radar Level Transmitters

Step 2: Analog Output Signal Validation

Figure 5-2. Simulation Mode ­[LT-01)

NOTE

This section refers to 4-20 mA/HART units only.

Ensure that the loop has been set to manual mode in the DCS for the
applicable transmitter.

Use the transmitter’s built-in simulation mode to verify the analog output
settings. Output at least one arbitrary level or interface and verify that the
reading in the DCS match up.

Rosemount Radar Master > Tools > Simulation Mode

Figure 5-3. Loop test for Analog
Out 1 - [LT-01]

Also, or alternatively, activate the transmitter’s loop test function. Output 4, 12,
and 20 mA and verify that the reading in the DCS match up.

Rosemount Radar Master > Output > Analog Out > Loop Test

5-3

Rosemount Radar Level Transmitters

UNZ

Surface
peak

Interface
peak

Interface
threshold

Surface
threshold

Reference
peak

Distance

Amplitude

Reference Manual

00809-0200-4530, Rev AB

September 2009

Step 3: Echo-Curve Verification at Operating Conditions

Figure 5-4. Peak amplitudes and
threshold settings

At normal operating conditions, download and review the echo-curve
according to the following steps:

1. Check Reference Pulse amplitude and position
Compare the result against the previous plots, taken during
commissioning, and previous verification rounds.

2. Review peak amplitudes and threshold settings
Verify that the surface and/or interface peaks are visible and that the
thresholds have been set according to the best practices in Section 6,
”Troubleshooting Procedures”. If possible, compare the current
echo-curve with previously stored echo-curves taken during operating
conditions. There should be no major differences.

3. Store the echo-curve
Permanently store the echo-curve for future use, with re-occurring
verification procedures.

Step 4: Transmitter Diagnostics Review

Figure 5-5. Diagnostics - [LT-01]

5-4

The transmitter contains valuable diagnostics that monitor the health of the
device to make sure that it does not report any errors or warnings.

Rosemount Radar Master > Tools > Diagnostics

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September 2009

Rosemount Radar Level Transmitters

Step 5: Monitor Level while Emptying

Figure 5-6. Log Registers

During Step 1, the current level/interface reading was verified correct. This
step will verify that the transmitter correctly tracks the surface during the
emptying of the tank.

Begin by activating log functionality for the transmitter level/interface output.
Either the DCS-trend or a stand-alone tool can be used:

Rosemount Radar Master > Tools > Log

Figure 5-7. Emptying a tank or
chamber

Start emptying the tank or chamber making sure not to stop until it is
completely empty. With a chamber, do not forget to close the process valves
before draining.

2: Open
vent

1: Close valves

3: Open
drain

5-5

Rosemount Radar Level Transmitters

Finally, review the level/interface trend for accuracy.

Reference Manual

00809-0200-4530, Rev AB

September 2009

Step 6: Echo-Curve Verification with Empty Tank

Step 7: Monitor Level while Filling

When the tank or chamber is empty, download and review the echo-curve
according to the following steps:

1. Compare echo-curve with previous plots
Compare the echo-curve with previous plots, taken during
commissioning. There should be no major differences. Especially make
sure to review:

• the amplitude and position of the reference pulse

• if all noise is below the threshold

• the amplitude and position of the bottom or probe-end pulse.

2. Store the echo-curve
Permanently store the echo-curve for future use, with re-occurring
verification procedures.

Repeat Step 5, but fill the tank or chamber instead of emptying it.

5-6

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00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Section 6 Troubleshooting Procedures

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 6-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 6-2

Echo Curve Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 6-3

SAFETY MESSAGES Procedures and instructions in this section may require special precautions to

ensure the safety of the personnel performing the operations. Information that
raises potential safety issues is indicated by a warning symbol ( ). Please
refer to the following safety messages before performing an operation
preceded by this symbol.

Explosions could result in death or serious injury.

Verify that the operating environment of the gauge is consistent with the appropriate
hazardous locations certifications.

Before connecting a HART-based communicator in an explosive atmosphere, make
sure the instruments in the loop are installed in accordance with intrinsically safe or
non-incendive field wiring practices.

Do not remove the gauge cover in explosive atmospheres when the circuit is alive.

Failure to follow safe installation and servicing guidelines could result in death or
serious injury.

Make sure only qualified personnel perform the installation.

Use the equipment only as specified in this manual. Failure to do so may impair the
protection provided by the equipment.

Do not perform any service other than those contained in this manual unless you are
qualified.

High voltage that may be present on leads could cause electrical shock.

Avoid contact with leads and terminals.

Make sure the main power to the transmitter is off and the lines to any other external
power source are disconnected or not powered while wiring
the gauge.

Probes covered with plastic and/or with plastic discs may generate an ignition-capable
level of electrostatic charge under certain extreme conditions. Therefore, when the
probe is used in a potentially explosive atmosphere, appropriate measures must be
taken to prevent electrostatic discharge.

www.rosemount.com

Reference Manual

NOTICE

00809-0200-4530, Rev AB

Rosemount Radar Level Transmitters

September 2009

INTRODUCTION This section provides helpful information in identifying the most common

problems found with radar level transmitters.

A typical work-flow may look like this (local restrictions and variations may
apply):

1. View DCS-trends and question the relevant people to understand when
the problem occurs and the effect of the problem. Could it be related to
any other activities?

2. Do a tank survey to identify the application. Ensure that the transmitter
has been selected according to Section 2 ”Installation Considerations”,
and Section 3 ”Refining Applications”.

3. Check for basic errors, such as wiring and transmitter diagnostics, then
complete relevant parts of Section 4 ”Commissioning” again.

4. If necessary, execute the verification procedure described in Section 5
”Measurement Validation at Operating Conditions”, or other procedure
that recreates the problem.

5. A) If the measurement is reliable, but there is an offset or the accuracy is
poor, refer to “Echo Curve Analysis“ on page 6-3.

B) Do an echo curve analysis as described in “Echo Curve Analysis“ on
page 6-3 to try to identify the problem.

When the problem has been resolved, the validation procedure described in
Section 5 ”Measurement Validation at Operating Conditions” should be
completed, or any other procedure that verifies the integrity of the transmitter.

In case the problem cannot be resolved, contact your local Rosemount
representative for assistance with a description of the problem, and be able to
submit the echo curve (.dat) and the transmitter backup file (.bak).

Read the product manual before working with the product. For personal and system safety,
and for optimum product performance, make sure you thoroughly understand the contents
before installing, using, or maintaining the product.

Within the United States, Rosemount Inc. has two toll-free assistance numbers.

Customer Central: 1-800-999-9307(7:00 a.m. to 7:00 p.m. CST)
Technical support, quoting, and order-related questions.

North American Response Center:

Equipment service needs.

1-800-654-7768 (24 hours a day – Includes Canada)

For equipment service or support needs outside the United States, contact your local
Rosemount representative.

6-2

Reference Manual

Reference
peak

Surface peak

Interface peak

Amplitude

Distance

Amplitude

Distance

Reference
peak

Surface
peak

Interface
peak

UNZ Interface

threshold

Surface
threshold

As presented in
Rosemount RadarMaster

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Echo Curve Analysis The echo curve represents the tank, as seen by the radar transmitter. Each

peak corresponds to a reflection of the radar signal - the surface of the level or
interface, an obstacle, or something else. By viewing single instances or
movies of the echo curve, how and why the transmitter behaves as it does
can be understood, and it can be configured accordingly to achieve a reliable
level measurement. Usually, an echo curve analysis is not needed; the
transmitter automatically sets the appropriate parameters based on the
start-up information such as tank height and tank media; however, it is a very
valuable tool for troubleshooting difficult applications.

Echo Curve Constituents

In a typical measurement situation the following peaks appear in the echo
curve:

Reference peak. This reference pulse is caused by the transition between
transmitter head and probe/antenna. For the 5300 Series, the pulse is
negative, while for the 5400 and 5600 Series, the pulse is positive.

6-3

Rosemount Radar Level Transmitters

Surface peak. This pulse is caused by a reflection from the product surface.

Interface peak (5302 only). This pulse is caused by the reflection from the

interface between the upper and lower product. This peak will only be
identified by the transmitter when it is configured for Measurement Mode
Level & Interface.

Table 6-1. Typical peak
amplitudes for Rosemount 5300
Series with single lead probe in
4 in. chambers

Reference peak

Surface peak, 5301 with oil (DC=2) ~2,000 mV

Surface peak, 5301 with water (DC=80) at 3 ft
(1 m) distance

Interface peak, 5302 with oil and water ~8,000 mV

(1) This value does not apply and may be considerably lower when the probe is completely submerged

in product.

Various amplitude thresholds are used to filter out unwanted signals and pick
up the different peaks. The transmitter uses certain criteria to select which
peaks correspond to the actual level and interface surfaces.

Peak

Reference Manual

00809-0200-4530, Rev AB

September 2009

Approximate signal strength, ideal

conditions for single lead probe in 4 in.

(100 mm) chambers

~10,000 mV

~10,000 mV

(1)

Counting from the top of the tank, the first echo above the Surface Threshold
is considered the product surface. Pulses further away from the top, although
above the Surface Threshold, are ignored. When the surface echo is found,
the next pulse below the product surface with a signal strength above the
Interface Threshold is considered the Interface.

Surface Threshold - amplitude threshold for detection of the Product level
peak. The surface threshold is designed as a number of individually
adjustable amplitude threshold points, the Amplitude Threshold Curve (ATC).

Interface Threshold (5300 only) - known as amplitude threshold for detection
of the Interface level peak.

Upper Null Zone / Hold Off Distance - measurements are not performed
within the Upper Null Zone (UNZ) / Hold Off Distance, so consequently, the
UNZ / Hold Off can be used to avoid measurements above a certain level, for
example because of disturbances in the nozzle.

6-4

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00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

5300 Threshold Settings

Recommendations for the Rosemount 5300 Series:

1. Use the automatic threshold settings and ensure that the dielectric
constants of the upper and lower products have been entered correctly

2. If needed, apply the ’Measure & Learn’ function

3. If needed, use the following best practices to apply custom threshold
adjustments:

• Generally, the threshold should be at 40-50% of the surface peak.
Example: If the surface is 2000 mV, the threshold should be set at
800-1000 mV.

• It should never be closer than 300 mV to any disturbing objects.
Example: If there is a 1100 mV peak from an inlet-pipe, the threshold
around it should be 1400 mV.

• The threshold should never be below 800 mV in the range 0-1 ft (0.3 m)
and never below 500 mV from 1 ft (0.3 m) upwards.

For products with very low dielectric contants, such as boiling hydrocarbons
and solids, it may be required to lower the threshold additionally, and/or to
activate the Probe End Projection (PEP) function.

5400/5600 Threshold Settings

Recommendations for the Rosemount 5400 and 5600 Series:

1. Apply the ’Measure & Learn’ function (only 5400 Series)

2. If needed, use the following best practices to apply custom threshold
adjustments:

• Generally, the threshold should be at 20% of the surface peak.
Example:
400 mV.

• It should never be closer than 200 mV to any disturbing objects.
Example: If there is a 500 mV peak from an obstacle, the threshold
around it should be 700 mV.

• The threshold should never be below 300 mV.

For products with very low dielectric constants, such as solids, it may be
required to lower the threshold additionally.

If the surface is 2000 mV, then the threshold should be set at

6-5

Rosemount Radar Level Transmitters

Amplitude

Distance

Surface threshold
(ATC)

Rosemount
5301

The surface peak is undetected
becuase it is below the surface
threshold.

Amplitude

Distance

Surface threshold
(ATC)

Rosemount
5301

The surface peak is detected
becuase it is above the surface
threshold.

Common Problems

Threshold below the surface peak

In this example, the threshold has incorrectly been set above the surface
peak (Figure 6-1). The problem can be corrected by lowering the threshold
(Figure 6-2).

Figure 6-1. Surface peak is
below the surface threshold

Reference Manual

00809-0200-4530, Rev AB

September 2009

Figure 6-2. Surface peak is
above the surface threshold

6-6

Reference Manual

Amplitude

Distance

Rosemount
5301

Surface threshold
(ATC)

The reflection from the air gap is selected
as the interface level because it is the
first peak above the surface threshold.

Surface threshold
(ATC)

Actual interface
level

UNZ

Amplitude

Distance

Rosemount
5301

Surface threshold
(ATC)

The peak from the interface level is now
correctly identified; it is the first peak
above the surface threshold outside the
UNZ.

Amplitude

Distance

Rosemount
5301

Surface threshold
(ATC)

The peak from the interface level is now
correctly identified; it is the first peak
above the surface threshold.

00809-0200-4530, Rev AB
September 2009

Figure 6-3. The interface level is
the reflection from the air gap

Rosemount Radar Level Transmitters

Air-gap misinterpreted as interface level

In this example, the transmitter incorrectly identifies the reflection from the
air-gap as the interface level (Figure 6-3). The problem can be corrected by
increasing the UNZ (Figure 6-4) or increasing the threshold (Figure 6-5).

Figure 6-4. Peak above the
surface threshold outside the
UNZ

Figure 6-5. Peak above the
surface threshold

Interface misinterpreted as level

6-7

Rosemount Radar Level Transmitters

Amplitude

Distance

Rosemount
5302

Surface threshold
(ATC)

Interface
threshold

The interface level is incorrectly
identified as the product surface because
the surface threshold is set too high.

Amplitude

Distance

Rosemount
5302

Surface threshold
(ATC)

Correct identification of surface
and interface peaks.

In this example, the transmitter incorrectly identifies the reflection from the
interface as the product surface, because it is the first peak above the surface
threshold (Figure 6-6). The problem can be solved by lowering the surface
threshold (Figure 6-7), and ensuring that the interface threshold is below the
interface peak.

Figure 6-6. Incorrect interface
level, surface threshold set too
high

Reference Manual

00809-0200-4530, Rev AB

September 2009

Figure 6-7. Correct identification
of surface and interface peaks

6-8

Reference Manual

Amplitude

Distance

Rosemount
5301

Actual
level

The reflection from the inlet-pipe is
selected as the surface because it is the
first peak above the surface threshold.

Surface threshold
(ATC)

Amplitude

Distance

Rosemount
5301

Surface threshold
(ATC)

The peak from the actual level is now
correctly identified; it is the first peak above
the surface threshold.

00809-0200-4530, Rev AB
September 2009

Figure 6-8. The surface is the
reflection from the inlet-pipe

Rosemount Radar Level Transmitters

Disturbance misinterpreted as level

In this example, the transmitter incorrectly identifies the reflection from an
inlet-pipe as the product surface, because it is the first peak above the surface
threshold (Figure 6-8). The problem can be solved by increasing the surface
threshold (Figure 6-9) or, in some cases where the disturbance is close to the
transmitter flange, by increasing the UNZ or performing the ’Near Zone Trim’
command.

Figure 6-9. Surface peak
identified correctly

6-9

Rosemount Radar Level Transmitters

Incorrect reading due to bent probe

If the probe has been bent, twisted, or similar in chamber installations, peaks
will appear randomly in the echo curve (Figure 6-10). If this is the case, the
mechanical installation will need to be redone ensuring that the
recommendations in Section 2 ”Installation Considerations” are followed. The
problem can often be resolved by adding a centering disk at the bottom of the
probe, but it may also require a replacement of the complete probe assembly.

Figure 6-10. Measurement data
using a bent probe

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September 2009

6-10

Reference Manual

Error

Error

Error

Inlet-pipe clogged

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Sources of Measurement Error

Figure 6-11. Installation error ­level/interface range is not
covered adequately

This section applies to radar level transmitters that tracks the surface, but
have poor accuracy or a fixed offset. There are many possible error sources
for this, such as incorrect settings or incorrect interpretation of the analog
output signal. These errors almost exclusively depend on the external
environment since radar is extremely accurate and does not drift.

Installation and Location Errors

Review the installation to determine what the transmitter is measuring and
what the expected output is.

In a chamber installation, check that the level/interface corresponds to the
value inside the tank. Ensure that the chamber has been installed where the
level/interface range can be adequately covered.

Figure 6-12. Inlet-pipe clogged

The connections between the vessel and the chamber must allow for flow of
the product. Clogging should be avoided.

6-11

Rosemount Radar Level Transmitters

Error

300 °F (150 °C)
SG=0.80

150 °F (65 °C)
SG=0.85

Incorrectly assumed to be on
the same level.

The radar transmitter is not temperature dependent. However, the fluid is, and
it expands and contracts with increased and decreased temperatures. With
certain fluids, the effect on level/interface level is noticeable in hot
applications with large differences in temperature between the chamber and
the tank. Insulating the chamber minimizes the temperature changes.

Figure 6-13. Temperature drop
in the chamber without
insulation

Reference Manual

00809-0200-4530, Rev AB

September 2009

Figure 6-14. The sight-glass and
chamber are not on the same
level where they are supposed
to be

Geometries

Review the tank geometry and check if any assumptions have been made
that caused the inaccuracies. For example, the location of a sight-glass or
secondary chamber may have been assumed to be at the same location as
the radar measurement, but in reality they are not.

Analog Output Settings

Review the analog output settings. The primary variable determines the
output, and is often set to Level. The definition is:

6-12

Level = Tank Height (Reference Gauge Height) - Measured Distance

Consequently, the zero level point is at "Tank Height (Reference Gauge
Height)" below the transmitter's flange. The LRV (4 mA setpoint) and URV (20
mA setpoint) should be set with this zero point as reference.

Probe Length and Tank Height (Reference Gauge Height) do not need to
match.

Reference Manual

Upper Reference Point

20 mA Upper Range Value
(URV) = 100 %

4 mA Lower Range Value
(LRV) = 0 %

Lower Reference Point
(Level = 0)

Tank Height (Reference

Gauge Height

Range 0 - 100 %

00809-0200-4530, Rev AB
September 2009

Figure 6-15. Analog output
settings - range values and
reference points

Rosemount Radar Level Transmitters

Figure 6-16. Dielectric Constant
Calculator - [LT-01]

Incorrect Dielectric Constant of the Upper Product

The Interface Level and Upper Product Thickness in interface applications are
calculated values. If an incorrect dielectric constant of the upper product is
used, it will result in inaccurate measurement (Product Level is not affected).
If this is the problem, the following tools can be used:

Rosemount Radar Master > Tank/Environment > Dielectric Constant

Calculator

6-13

Rosemount Radar Level Transmitters

Rosemount 5301

Air gap

Interface Level offset = Air gap distance X ( 1 -

1

dielectric constant of upper product

)

Rosemount Radar Master > Tank/Environment > Dielectric Constant Chart

Figure 6-17. Dielectric Constant
Chart

Reference Manual

00809-0200-4530, Rev AB

September 2009

Figure 6-18. Submerged probe
with air gap

Submerged Probes with Air gap

Where the Rosemount 5301 has an air gap in an application for interface
measurement with a submerged probe, an offset in the interface level
measurement will be generated according to:

Figure 6-19. Formula for the
calculation of Interface Level
Offset

6-14

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

For example, an air gap of 4 in. (100 mm) with oil as the upper product (dc=2)
generates a 1 in. (25 mm) positive level offset. If the air gap is constant and
cannot be removed, the interface level output can be compensated by
reducing the reference height with the offset. Alternatively, using the
Rosemount 5302 automatically compensates for the air gap, including
changing air gaps.

Incorrect Vapor Compensation

A few specific high-temperature and high-pressure applications, like saturated
water steam, requires a compensated value be entered for the vapor
dielectric constant. This compensation is fixed and will only adjust the level
reading at a specific condition. Normally, this means that the transmitter will
show a correct level reading during operation, but not during startup and
shutdown. Alternatively, if no correction is entered, the level reading will be
correct during shutdown but not during startup and operation. See Table 3-1
on page 3-4 and Table 3-2 on page 3-6.

Reconciling Radar with other Level Measurements

When comparing level measurements to each other, they often do not match
up as expected. There are numerous reasons for this with the most prominent
one being related to what is actually being measured. Few instruments
measure the level directly as radar does. Instead an indirect measurement of,
for example, pressure, pull-force, or capacitance is done, and then the level is
calculated from this measurement. Inaccuracies in the level measurement
may occur during the calculation process, or from the fact that what is thought
the measurement is for is not what is actually being measured.

Figure 6-20. Displacer used for
measurement

Displacer

Displacers are one of the most common methods to measure level. The
Archimedes' principle is used, and by measuring the apparent weight of the
immersed displacer, a level measurement can be indirectly measured.
Besides the possibility of the displacer getting stuck, it also requires precise
calibration. Any change in density, such as a different product in the tank or
changed temperature, will result in inaccuracies.

6-15

Rosemount Radar Level Transmitters

Wet Leg:

Level offset is

created by

incomplete fill

Density of fill

fluid must be

known

Dry Leg:

Level offset is

created by

condensed fluid

Example: A 50 in. displacer calibrated to SG 0.9 will only show a 44 in. level
reading at full range with a product that has a SG 0.8, resulting in a systematic
error of 50 - 44 = 6 in.

Differential Pressure (DP)

Another common method for measuring level is using Pressure or Differential
Pressure transmitters. These are examples of indirect level measurement
methods, where incorrect conversion or installation can result in inaccuracies.
Potential problems include:

• Fluid density changes: source, grade, product and temperature affect
the density of the fluid, and thereby the level output

• In case of a wet leg, is it completely filled? Or, if a dry leg is used, is it
really dry? Loss of fluid and condensed fluid respectively create an
offset in the level reading. Consider using either an electronic or
capillary remote seal

•If a fill fluid is used, is its density known? Has the transmitter been
scaled correctly?

• If a single pressure transmitter is used, process pressure will create an
offset in the level reading. Consider using a differential pressure
transmitter.

Reference Manual

00809-0200-4530, Rev AB

September 2009

Figure 6-21. Differential
pressure transmitter

6-16

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Appendix Checklists

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 7-1

Checklists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 7-2

Commissioning Procedure Checklist . . . . . . . . . . . . . . . . page 7-2

Measurement Validation at Operating Conditions Procedure Checklist
page 7-3

SAFETY MESSAGES Procedures and instructions in this section may require special precautions to

ensure the safety of the personnel performing the operations. Information that
raises potential safety issues is indicated by a warning symbol ( ). Please
refer to the following safety messages before performing an operation
preceded by this symbol.

Explosions could result in death or serious injury.

Verify that the operating environment of the gauge is consistent with the appropriate
hazardous locations certifications.

Before connecting a HART
sure the instruments in the loop are installed in accordance with intrinsically safe or
non-incendive field wiring practices.

Do not remove the gauge cover in explosive atmospheres when the circuit is alive.

Failure to follow safe installation and servicing guidelines could result in death or
serious injury.

Make sure only qualified personnel perform the installation.

Use the equipment only as specified in this manual. Failure to do so may impair the
protection provided by the equipment.

Do not perform any service other than those contained in this manual unless you are
qualified.

High voltage that may be present on leads could cause electrical shock.

Avoid contact with leads and terminals.

Make sure the main power to the transmitter is off and the lines to any other external
power source are disconnected or not powered while wiring
the gauge.

Probes covered with plastic and/or with plastic discs may generate an ignition-capable
level of electrostatic charge under certain extreme conditions. Therefore, when the
probe is used in a potentially explosive atmosphere, appropriate measures must be
taken to prevent electrostatic discharge.

®

-based communicator in an explosive atmosphere, make

www.rosemount.com

Rosemount Radar Level Transmitters

CHECKLISTS

Reference Manual

00809-0200-4530, Rev AB

September 2009

Commissioning Procedure Checklist

Instrument Identification

Ta g

Model-code

Serial Number

Service

Step Task Result Completed

1 Shorten the Probe New Probe Length:___________________________

Mount Centering disk Disk diameter:_____________________________

2

Mechanical Installation Probe

3

4 Anchor Flexible Probe Method:____________________________________

Electrical Installation Power supply:______________________________

5

Transmitter Configuration Configuration Tool:__________________________

6

7 Trim Near Zone Command Executed:__________________________

Store Backup and Verification

8

Files

9 On the Bench Test Method:____________________________________

Measurement Validation at

10

Operating Conditions

(1)NA = Not Applicable

The commissioning procedure has been carried out according to the Quick
Installation Guide enclosed to the transmitter.

(1)

Cage diameter:______________________________

- mechanical integrity:_______________________

- wetted material process compliance:___________

- P/T process compliance:____________________
Gasket:____________________________________

Communication:____________________________
I/O:______________________________________
Hazardous Location Classification:_______________

Tag:______________________________________
Tank Height (Reference Gauge Height:__________
Product Dielectric:___________________________
LRV (4 mA):________________________________
URV (20 mA):_______________________________

File paths:

- Echo-Curve:______________________________

- Settings:__________________________________

See separate check-list

Yes / No / NA

Yes / No / NA

Yes / No

Yes / No / NA

Yes / No / NA

Yes / No

Yes / No / NA

Yes / No

Yes / No

Yes / No

7-2

Comments:_________________________________________________________________

__________________________________________________________________________

__________________________________________________________________________

__________________________________________________________________________

__________________________________________________________________________

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

Measurement Validation at Operating Conditions Procedure Checklist

Instrument Identification

Ta g

Model-code

Serial Number

Service

Step Completed Task Result Passed

1 Yes / No

2 Ye s / N o

3 Yes / No

4 Ye s / N o

5 Yes / No

6 Ye s / N o

7 Yes / No

Verify correctness of Level Reading

Analog Output Signal Validation
(4-20mA/HART units only)

Echo-Curve verification at operating
conditions

Transmitter Diagnostics Review Active Warnings:______________

Monitor Level while emptying Transmitter output:____________ Yes / No

Echo-Curve verification with empty
tank or chamber

Monitor level while filling Transmitter output:____________ Yes / No

The validation procedure has been carried out according to Section 6 in the
document Rosemount Process Radars in Refining Applications - Best
Practices Supplement to Reference Manual (00809-0100-xxxx, Rev AA).

Radar Level Reading:__________

Second Level device:__________

Second Level Reading:_________
Radar Output (Level):__________

Radar Output (mA):___________

DCS Reading(%):_____________

DCS Reading (mA):___________
Reference peak:______________

Surface threshold:____________

Interface threshold:____________

Echo Curve File Location:_______

Active Errors:________________

Reference peak: _____________

Noise level:__________________

Bottom/Probe-end peak:________

Echo Curve File Location:_______

Yes / No

Yes / No

Yes / No

Yes / No

Yes / No

Comments:____________________________________________________________________

_____________________________________________________________________________

_____________________________________________________________________________

____________________________________________________________________________

Result:

Transmitter failed

Transmitter passed

7-3

Rosemount Radar Level Transmitters

Reference Manual

00809-0200-4530, Rev AB

September 2009

7-4

Reference Manual

00809-0200-4530, Rev AB
September 2009

Rosemount Radar Level Transmitters

The Emerson logo is a trademark and service mark of Emerson Electric Co.
Rosemount and the Rosemount logotype are registered trademarks of Rosemount Inc.
HART is a registered trademark of the HART Communication Foundation.
Modbus is a registered trademark of Modicon.
PlantWeb is a registered trademark of one of the Emerson Process Management group of companies.
Teflon, VITON, and Kalrez are registered trademarks of DuPont Performance Elastomers.
Asset Management Solutions is a trademark of Emerson Process Management.
All other marks are the property of their respective owners.

Standard Terms and Conditions of Sale can be found at www.rosemount.com\terms_of_sale.

© 2009 Rosemount Inc. All rights reserved.

Emerson Process Management
Rosemount Measurement

8200 Market Boulevard
Chanhassen MN 55317 USA
T (USA) 1 800 999 9307
T (International) [phone]
F [phone]

00809-0200-4530 Rev AB 09/09

Emerson Process Management

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P.O. Box 1046

CH 6341 Baar
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Tel [phone]
Fax [phone]

Emerson FZE

P.O. Box 17033
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Service Support Hotline: [phone]
Email: [e-mail]