Rosemount Manual: 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
www.rosemount.com
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
www.rosemount.com
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
www.rosemount.com
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.
www.rosemount.com
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
www.rosemount.com
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
Loading...
+ 50 hidden pages