Emerson Rosemount 700XA User manual

Reference Manual
2-3-9000-744, Rev L
June 2022
Rosemount™ 700XA
Gas Chromatograph

Notice
EMERSON (“SELLER”) SHALL NOT BE LIABLE FOR TECHNICAL OR EDITORIAL ERRORS IN THIS MANUAL OR OMISSIONS FROM THIS
MANUAL. SELLER MAKES NO WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, WITH RESPECT TO THIS MANUAL AND, IN NO EVENT, SHALL
SELLER BE LIABLE FOR ANY SPECIAL OR CONSEQUENTIAL DAMAGES INCLUDING, BUT NOT LIMITED TO, LOSS OF PRODUCTION,
LOSS OF PROFITS, ETC.
PRODUCT NAMES USED HEREIN ARE FOR MANUFACTURER OR SUPPLIER IDENTIFICATION ONLY AND MAY BE TRADEMARKS/
REGISTERED TRADEMARKS OF THESE COMPANIES.
THE CONTENTS OF THIS PUBLICATION ARE PRESENTED FOR INFORMATIONAL PURPOSES ONLY AND, WHILE EVERY EFFORT HAS
BEEN MADE TO ENSURE THEIR ACCURACY, THEY ARE NOT TO BE CONSTRUED AS WARRANTIES OR GUARANTEES, EXPRESSED OR
IMPLIED, REGARDING THE PRODUCTS OR SERVICES DESCRIBED HEREIN OR THEIR USE OR APPLICABILITY. WE RESERVE THE RIGHT
TO MODIFY OR IMPROVE THE DESIGNS OR SPECIFICATIONS OF SUCH PRODUCTS AT ANY TIME.
SELLER DOES NOT ASSUME RESPONSIBILITY FOR THE SELECTION, USE, OR MAINTENANCE OF ANY PRODUCT. RESPONSIBILITY FOR
PROPER SELECTION, USE, AND MAINTENANCE OF ANY SELLER PRODUCT REMAINS SOLELY WITH THE PURCHASER AND END-USER.
Warranty
1. LIMITED WARRANTY: Subject to the limitations contained in Section 2 herein and except as otherwise expressly provided
herein, Emerson (“Seller”) warrants that the firmware will execute the programming instructions provided by Seller and
that the Goods manufactured or Services provided by Seller will be free from defects in materials or workmanship under
normal use and care until the expiration of the applicable warranty period. Goods are warranted for twelve (12) months
from the date of initial installation or eighteen (18) months from the date of shipment by Seller, whichever period expires
first. Consumables and Services are warranted for a period of 90 days from the date of shipment or completion of the
Services. Products purchased by Seller from a third party for resale to Buyer (“Resale Products”) shall carry only the
warranty extended by the original manufacturer. Buyer agrees that Seller has no liability for Resale Products beyond
making a reasonable commercial effort to arrange for procurement and shipping of the Resale Products. If Buyer
discovers any warranty defects and notifies Seller thereof in writing during the applicable warranty period, Seller shall, at
its option, promptly correct any errors that are found by Seller in the firmware or Services, or repair or replace F.O.B. point
of manufacture that portion of the Goods or firmware found by Seller to be defective, or refund the purchase price of the
defective portion of the Goods/Services. All replacements or repairs necessitated by inadequate maintenance, normal
wear and usage, unsuitable power sources, unsuitable environmental conditions, accident, misuse, improper installation,
modification, repair, storage or handling, or any other cause not the fault of Seller are not covered by this limited
warranty, and shall be at Buyer's expense. Seller shall not be obligated to pay any costs or charges incurred by Buyer or any
other party except as may be agreed upon in writing in advance by an authorized Seller representative. All costs of
dismantling, reinstallation and freight, and the time and expenses of Seller's personnel for site travel and diagnosis under
this warranty clause shall be borne by Buyer unless accepted in writing by Seller. Goods repaired and parts replaced during
the warranty period shall be in warranty for the remainder of the original warranty period or ninety (90) days, whichever is
longer. This limited warranty is the only warranty made by Seller and can be amended only in a writing signed by an
authorized representative of Seller. Except as otherwise expressly provided in the Agreement, THERE ARE NO
REPRESENTATIONS OR WARRANTIES OF ANY KIND, EXPRESSED OR IMPLIED, AS TO MERCHANTABILITY, FITNESS FOR
PARTICULAR PURPOSE, OR ANY OTHER MATTER WITH RESPECT TO ANY OF THE GOODS OR SERVICES. It is understood
that corrosion or erosion of materials is not covered by our guarantee.
2. LIMITATION OF REMEDY AND LIABILITY: SELLER SHALL NOT BE LIABLE FOR DAMAGES CAUSED BY DELAY IN
PERFORMANCE. THE SOLE AND EXCLUSIVE REMEDY FOR BREACH OF WARRANTY HEREUNDER SHALL BE LIMITED TO
REPAIR, CORRECTION, REPLACEMENT, OR REFUND OF PURCHASE PRICE UNDER THE LIMITED WARRANTY CLAUSE IN
SECTION 1 HEREIN. IN NO EVENT, REGARDLESS OF THE FORM OF THE CLAIM OR CAUSE OF ACTION (WHETHER BASED IN
CONTRACT, INFRINGEMENT, NEGLIGENCE, STRICT LIABILITY, OTHER TORT, OR OTHERWISE), SHALL SELLER'S LIABILITY TO
BUYER AND/OR ITS CUSTOMERS EXCEED THE PRICE TO BUYER OF THE SPECIFIC GOODS MANUFACTURED OR SERVICES
PROVIDED BY SELLER GIVING RISE TO THE CLAIM OR CAUSE OF ACTION. BUYER AGREES THAT IN NO EVENT SHALL
SELLER'S LIABILITY TO BUYER AND/OR ITS CUSTOMERS EXTEND TO INCLUDE INCIDENTAL, CONSEQUENTIAL, OR PUNITIVE
DAMAGES. THE TERM “CONSEQUENTIAL DAMAGES” SHALL INCLUDE, BUT NOT BE LIMITED TO, LOSS OF ANTICIPATED
PROFITS, LOSS OF USE, LOSS OF REVENUE, AND COST OF CAPITAL.
Safety information
NOTICE
The analyzer electronics and oven assembly, when housed inside a purged enclosure, meet the certifications and classifications
identified in the Specifications section of the Product Data Sheet, which is located on the Emerson website: emerson.com.
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WARNING
Safety compliance
Failure to follow the safety instructions may cause injury to personnel. The seller does not accept any responsibility for installations
of the device or any attached equipment in which the installation or operation thereof has been performed in a manner that is
negligent and/or non-compliant with applicable safety requirements.
Install and operate all equipment as designed and comply with all safety requirements.
If the device is not operated in a manner recommended by the manufacturer, the overall safety could be impaired.
Observe all safety precautions defined in the gas Safety Data Sheet (SDS), especially for hazardous locations.
WARNING
Supply mains connection
The device is intended to be connected to supply mains by qualified personnel in accordance with local and national codes.
WARNING
Explosion
Failure to de-energize the analyzer may cause an explosion and severely injure personnel.
Before opening the analyzer, disconnect all electrical power and ensure that the area is free of explosive gases.
Keep cover tight while circuits are live.
Use cables or wires suitable for the marked "T" ratings.
Cover joints must be cleaned before replacing the cover.
Conduit runs to the enclosure must have sealing fitting adjacent to enclosure.
WARNING
Power
A suitable APPROVED switch and fuse or a circuit breaker shall be provided to facilitate the disconnection of mains power.
WARNING
Ventilation
Use the device in a well-ventilated area.
If you plan to place the device in a sealed shelter, always vent it to atmosphere with 0.25 in (6.4 mm) tubing or larger. This will
prevent the build up of H2 and sample gas.
WARNING
Leak testing
All gas connections must be properly leak tested at installation.
Do not turn on gas until you have completely checked the carrier lines for leaks.
WARNING
Precautionary signs
Failure to observe precautionary signs may result in injury or death to personnel or cause damage to equipment.
Observe and comply with all precautionary signs posted on the device.
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WARNING
Toxic vapors
Exit ports may discharge dangerous levels of toxic vapors.
Use proper protection and a suitable exhaust device.
WARNING
Burns
Some parts of the analyzer may be heated to 248 °F (120 °C).
To prevent burns, do not touch any of the hot parts. All parts of an analyzer are always hot unless it has been switched off and
allowed to cool down.
Before fitting, removing, or performing any maintenance on the analyzer, make sure that it has been switched off and allowed
to cool for at least two hours.
When handling the analyzer, always use suitable protective gloves.
These precautions are particularly important when working at heights.
If burned, seek medical treatment immediately.
WARNING
Physical access
Unauthorized personnel may potentially cause significant damage to and/or misconfiguration of end users’ equipment. This could
be intentional or unintentional and needs to be protected against.
Physical security is an important part of any security program and fundamental to protecting your system. Restrict physical access
by unauthorized personnel to protect end users' assets. This is true for all systems used within the facility.
NOTICE
Replaceable parts
Only a few parts inside the device are replaceable. Only trained service personnel should replace parts.
All replacement parts must be authorized by Emerson to ensure product certification compliance.
NOTICE
Equipment damage
If the device is heated without carrier flow, damage to the columns may occur.
NOTICE
Waste disposal
Waste electrical and electronic products must not be disposed of with household waste.
Please recycle where facilities exist.
Check with your local authority or retailer for recycling advice.
NOTICE
The device is certified by CSA and ATEX. See the certification tag on the device for specific details about its agency approvals.
When the vapor regulators and flow switches are fitted, they must be suitably certified with the ratings Ex d IIC Gb T6/T4/T3 and
for a minimum ambient temperature range: Ta = -20 °C to +60 °C.
Where right angle bend cable adapters are used, they shall be appropriately certified and shall interface with enclosures via
appropriate certified barrier glands.
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Glossary
Auto zero The thermal conductivity detector (TCD) is auto zeroed at the start of a new analysis. The operator can also
configure automatic zeroing of the TCD amplifier to take place at any time during the analysis if the
component is not eluting or the baseline is steady. The flame ionization detector (FID) will auto zero at each
new analysis run and can be configured to auto zero anytime during the analysis if the component is not
eluting or the baseline is steady.
Baseline Signal output when there is only carrier gas going across the detectors. In a chromatogram you should only
see Baseline when running an analysis without injecting a sample.
Carrier gas The gas used to push the sample through the system during an analysis.
CDT Component data table.
Chromatogram A permanent record of the detector output. A chromatogram is obtained from a personal computer (PC)
interfaced with the detector output through the controller assembly. A typical chromatogram displays all
component peaks and gain changes. It may be viewed in color as it is processed on a PC display. Check marks
recorded on the chromatogram by the controller assembly indicate where timed events take place.
Component Any one of several different gases that may appear in a sample mixture. For example, natural gas usually
contains the following components: nitrogen, carbon dioxide, methane, ethane, propane, isobutane, normal
butane, isopentane, normal pentane, and hexanes plus.
CTS Clear to send.
DCD Data carrier detect.
DSR Data set ready.
DTR Data terminal ready.
FID Flame ionization detector. The optional FID may be used in place of a TCD for the detection of trace
compounds. The FID requires a polarization voltage, and its output is connected to the input to a high
impedance amplifier, an electrometer. The sample of gas to be measured is injected into the burner with a
mixture of hydrogen and air to maintain the flame.
FPD Flame photometric detector. The FPD is used to analyze gas compound impurities, such as sulfur,
phosphorous, and metals. When sample gas passes through the hydrogen/air flame the component's
wavelengths emitted are electrically measured. The FPD is located in the analyzer's upper enclosure.
GC Gas chromatograph. The GC is a user-configurable analyzer for various process gas applications.
LSIV Liquid sample injection valve. The optional LSIV is used to convert a liquid sample to a gas sample by
vaporizing the liquid in a heated chamber, so the resulting gas sample can be analyzed.
Methanator The optional methanator, also known as a catalytic converter, transforms the components that are
undetectable by the FID (carbon dioxide and/or carbon monoxide) into methane by adding hydrogen and
heat to the sample.
PC Personal computer.
Response factor Correction factor for each component as determined by the following calibration:
Retention time Time, in seconds, that elapses between the start of analysis and the sensing of the maximum concentration of
each component by the detector.
RI Ring indicator.
RLSD Received line signal detect. A digital simulation of a carrier detect.
RTS Request to send.
RxD, RD, or Sin Receive data or signal in.
SCS Sample conditioning system.
TCD Thermal conductivity detector. A detector that uses the thermal conductivity of the different gas
components to produce an unbalanced signal across the bridge of the preamplifier. The higher the
temperature, the lower the resistance on the detectors.
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TxD, TD, or Sout Transmit data or signal out.
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Contents
Chapter 1 Overview................................................................................................................... 9
1.1 System description...................................................................................................................... 9
1.2 Functional description............................................................................................................... 10
1.3 Software description..................................................................................................................12
1.4 Theory of operation................................................................................................................... 14
Chapter 2 Equipment description and specifications................................................................ 31
2.1 Equipment description.............................................................................................................. 31
2.2 Specifications............................................................................................................................ 39
Chapter 3 Getting started.........................................................................................................43
3.1 Select site.................................................................................................................................. 43
3.2 Unpack the gas chromatograph (GC).........................................................................................43
3.3 Required tools and components................................................................................................ 45
3.4 Supporting tools and components.............................................................................................46
Chapter 4 Installation and start-up .......................................................................................... 47
4.1 Installation considerations.........................................................................................................47
4.2 Mounting arrangements............................................................................................................47
4.3 Gas chromatograph wiring........................................................................................................ 51
4.4 Electrical installation..................................................................................................................55
4.5 Leak checking and purging for first calibration...........................................................................95
4.6 Start up the system....................................................................................................................98
Chapter 5 Operation and maintenance...................................................................................101
5.1 Warning and notice................................................................................................................. 101
5.2 Start a 2-point calibration........................................................................................................ 101
5.3 Troubleshooting and repair..................................................................................................... 102
5.4 Routine maintenance.............................................................................................................. 102
Chapter 6 Troubleshooting.................................................................................................... 183
6.1 Hardware alarms..................................................................................................................... 183
6.2 No power to flame photometric detector (FPD).......................................................................192
6.3 Can't ignite flame photometric detector (FPD)........................................................................ 192
6.4 No peaks showing....................................................................................................................192
6.5 Small peaks..............................................................................................................................193
6.6 No temperature readings.........................................................................................................193
6.7 Noisy baseline..........................................................................................................................193
6.8 Peak clipping........................................................................................................................... 193
6.9 Test points...............................................................................................................................194
6.10 Voltage LEDs..........................................................................................................................195
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6.11 Monitoring the detector(s) and columns temperature...........................................................196
Appendix A Local operator interface (LOI)................................................................................. 197
A.1 Local operator interface (LOI) for displaying and entering data................................................ 197
A.2 Using the local operator interface (LOI)................................................................................... 199
A.3 Navigate and interact with the screen......................................................................................212
A.4 Local operator interface (LOI) screens......................................................................................220
A.5 Troubleshoot a blank local operator interface (LOI) display screen...........................................261
Appendix B Carrier gas installation and maintenance................................................................263
B.1 Carrier gas............................................................................................................................... 263
B.2 Install manifold and purge line.................................................................................................264
B.3 Replace carrier cylinder............................................................................................................265
B.4 Calibration gas for BTU analysis ...............................................................................................265
Appendix C Micro flame photometric detector (µFPD).............................................................. 267
C.1 Configure the micro flame photometric detector (µFPD).........................................................268
Appendix D Recommended spare parts.....................................................................................271
D.1 Recommended spare parts for Rosemount 700XA thermal conductivity detector (TCD)
analyzers...................................................................................................................................271
D.2 Recommended spare parts for Rosemount 700XA flame ionization detector (FID)/thermal
conductivity detector (TCD) analyzers...................................................................................... 272
D.3 Recommended spare parts for Rosemount 700XA flame ionization detector (FID) analyzers.. 273
D.4 Recommended spare parts for Rosemount 700XA micro flame photometric detector
(µFPD) analyzers....................................................................................................................... 274
Appendix E Shipping and long-term storage recommendations................................................275
Appendix F Pre-defined Modbus® map files..............................................................................277
Appendix G Engineering drawings............................................................................................ 279
G.1 List of engineering drawings - Rosemount 700XA....................................................................279
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1 Overview
1.1 System description
The Rosemount 700XA is a high-speed gas chromatograph (GC) system that is engineered
to meet specific field application requirements based on typical hydrocarbon stream
composition and anticipated concentration of selected components. In its standard
configuration, the analyzer can handle up to eight streams: seven sample streams and one
calibration stream.
The Rosemount 700XA system consists of two major parts: the analyzer assembly and the
electronics assembly. Depending upon the particular GC, there may also be a third,
optional assembly called the sample conditioning system (SCS).
The electronics and hardware are housed in an explosion-proof enclosure that meets the
approval guidelines of various certification agencies for use in hazardous environments.
See the certification tag on the GC for specific details about agency approvals.
1.1.1 Analyzer assembly
The analyzer assembly includes:
•Columns
•Thermal conductivity detectors (TCDs)
•Flame ionization detectors (FIDs)
•Flame photometric detector (FPD)
•Preamplifier
•Preamplifier power supply
•Stream switching valves
•Analytical valves
•Solenoids
Additionally, the gas chromatograph (GC) can be equipped with a liquid sample injection
valve (LSIV) or methanator.
Related information
Upper compartment
1.1.2 Electronics assembly
The electronics assembly includes the electronics and ports necessary for signal
processing, instrument control, data storage, personal computer (PC) interface, and
telecommunications.
The operator uses the electronics assembly and Rosemount MON2020 to control the gas
chromatograph (GC).
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The GC-to-PC interface provides you with the greatest capability, ease-of-use, and
flexibility. You can use Rosemount MON2020 to edit applications, monitor operations,
calibrate streams, and display analysis chromatograms and reports, which can then be
stored as files on the PC’s hard drive or printed from a printer connected to the PC.
WARNING
Hazardous area explosion hazard
Failure to follow this warning may result in injury or death to personnel.
Do not use a personal computer (PC) or printer in a hazardous area.
Emerson provides serial and Ethernet communication links to connect the analyzer to
the PC and to connect to other computers and printers in a safe area.
1.1.3 Sample conditioning system (SCS)
The optional sample conditioning system is located between the process stream and the
sample inlet, which is often mounted below the gas chromatograph (GC).
The standard SCS configuration includes a stream switching system and filters.
1.2 Functional description
A sample probe installed in the process line takes a sample of the gas to be analyzed from
the process stream. The sample passes through a sample line to the sample conditioning
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system (SCS) where it is filtered or otherwise conditioned. After conditioning, the sample
flows to the analyzer assembly for separation and detection of the gas components.
Figure 1-1: Gas chromatography process model
A. Process line
B. Probe
C. Sample system
D. Chromatograph oven
E. Gas chromatograph (GC) controller
F. Sample return
G. Slip stream
H. Carrier gas
I. Reference vent
J. Detector vent
K. Analysis results
Separation and analysis
The GC separates the sample gas into its components as follows:
1. A precise volume of sample gas is injected into one of the analytical columns. The
column contains a stationary phase (packing) that is either an active solid or an inert
solid support that is coated with a liquid phase (absorption partitioning).
2. A mobile phase (carrier gas) moves the sample gas through the column.
3. The selective retardation of the components takes place in the column, causing
each component to move through the column at a different rate. This separates the
sample into its constituent gases and vapors.
4. A detector located at the outlet of the analytical column senses the elution of
components from the column and produces electrical outputs proportional to the
concentration of each component.
Output from the electronic assembly is normally displayed on a remotely located personal
computer (PC) or in a distributed control system (flow computer).
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To connect the GC to a PC, use a direct serial line, an optional Ethernet cable, or a
Modbus®-compatible communication interface.
Several chromatograms may be displayed via Rosemount MON2020 with separate color
schemes, allowing you to compare present and past data.
In most cases, it is essential to use Rosemount MON2020 to configure and troubleshoot
the GC. The PC may be remotely connected via Ethernet, telephone, radio, or satellite
communications. Once installed and configured, the GC can operate independently for
long periods of time.
1.3 Software description
The gas chromatograph (GC) uses two distinct types of software. This enables total
flexibility in defining the calculation sequence, report content, format, type and amount of
data for viewing, control, and/or transmission to another computer or controller
assembly.
The two types are:
•Embedded GC firmware
•Rosemount MON2020 software
The RTOS firmware and the application configuration software are installed when the
Rosemount 700XA is shipped.
The application configuration is tailored to the customer’s process and shipped on a USB
stick. The hardware and software are tested together as a unit before the equipment
leaves the factory.
Rosemount MON2020 communicates with the GC and can be used to initiate site system
setup, such as operational parameters, application modifications, and maintenance.
1.3.1 Embedded gas chromatograph (GC) firmware
The GC’s embedded firmware supervises operation of the Rosemount 700XA through its
internal microprocessor-based controller.
All direct hardware interface is via this control software. It consists of a multitasking
program that controls separate tasks in system operation, as well as hardware self-testing,
user application downloading, start-up, and communication. After configuration, the GC
can operate as a stand-alone unit.
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1.3.2 Rosemount MON2020
The Rosemount MON2020 software provides the operator control of the gas
chromatograph (GC), monitors analysis results, and inspects and edits various parameters
that affect the analyzer operation. It also controls display and printout of the
chromatograms and reports, and it stops and starts automatic analysis cycling or
calibration runs.
After the equipment/software has been installed and the operation stabilized, automatic
operation takes place over an Ethernet network.
Rosemount MON2020 is a Windows™-based program that allows you to maintain,
operate, and troubleshoot a GC. Individual GC functions that can be initiated or controlled
by Rosemount MON2020 include, but are not limited to, the following:
•Valve activations
•Timing adjustments
•Stream sequences
•Calibrations
•Baseline runs
•Analyses
•Halt operation
•Stream/detector/heater assignments
•Stream/component table assignments
•Stream/calculation assignments
•Diagnostics
•Alarm and event processing
•Event sequence changes
•Component table adjustments
•Calculation adjustments
•Alarm parameters adjustments
•Analog scale adjustments
•Local operator interface (LOI) variable assignments (optional)
Reports and logs that can be produced, depending upon the GC application in use,
include, but are not limited to, the following:
•Configuration report
•Parameter list
•Analysis chromatogram
•Chromatogram comparison
•Alarm log (unacknowledged and active alarms)
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•Event log
•Various analysis reports
1.4 Theory of operation
Related information
Glossary
1.4.1 Thermal conductivity detector (TCD)
One of the detectors available on the gas chromatograph (GC) is a TCD, which consists of a
balanced bridge network with heat sensitive thermistors in each leg of the bridge. Each
thermistor is enclosed in a separate chamber of the detector block.
One thermistor is designated the reference element, and the other thermistor is
designated the measurement element. See Figure 1-2 for a schematic diagram of the TCD.
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Figure 1-2: Analyzer assembly with TCD bridge
A. Detector block (in heated oven section of analyzer)
B. Reference flow (carrier gas)
C. Measurement flow ("MV")
D. Signal out
E. Preamplifier (in analyzer electronics housing)
F. Detector bridge
G. DC power
H. Valves, columns, etc.
In the quiescent condition, prior to injecting a sample, both legs of the bridge are exposed
to pure carrier gas. In this condition, the bridge is balanced, and the bridge output is
electrically nulled.
The analysis begins when the sample valve injects a fixed volume of sample into the
column. The continuous flow of carrier gas moves the sample through the column. As
successive components elute from the column, the temperature of the measurement
element changes.
The temperature change unbalances the bridge and produces an electrical output
proportional to the component concentration.
The differential signal developed between the two thermistors is amplified by the
preamplifier. Figure 1-3 illustrates the change in detector electrical output during elution
of a component.
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Figure 1-3: Detector output during component elution
A. Detector bridge balanced
B. Component begins to elute from column and is measured by thermistor.
C. Peak concentration of component
In addition to amplifying the differential signal developed between the two thermistors,
the preamplifier supplies drive current to the detector bridge.
The signal is proportional to the concentration of a component detected in the gas
sample. The preamplifier provides four different gain channels as well as compensation for
baseline drift.
The signals from the preamplifier are sent to the electronic assembly for component
concentration computation, recording, or viewing on a personal computer (PC) with
Rosemount MON2020.
1.4.2 Flame ionization detector (FID)
Another detector available for the Rosemount 700XA is the flame ionization detector
(FID).
The FID requires a polarization voltage, and its output is connected to the input with a high
impedance amplifier that is called an electrometer. The burner uses a mixture of hydrogen
and air to maintain the flame. The sample of gas to be measured is also injected into the
burner. See Figure 1-4 for a schematic diagram of the FID.
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Figure 1-4: Analyzer assembly with FID detector bridge
A. Polarizing voltage
B. Electrometer
C. Signal out
D. Sample/hydrogen (H2)
E. Air
1.4.3 Micro flame photometric detector (µFPD) burner
The flame photometric detector (FPD) is a very sensitive and selective detector for the
analysis of sulfur or organophosphorus containing compounds. The detector is very stable
and easy to use.
As the analyte is burned in a hydrogen and air flame, a characteristic wavelength of light is
emitted at 394 nm for sulfur. The emitted light is amplified by the photomultiplier tube
(PMT) and processed by the signal processor. The response to phosphorus is linear and
quadratic to sulfur.
The Emerson µFPD solution consists of three key parts: burner, fiber cable, and PMT
electronics. The hydrogen and air in the burner help to burn the sample containing sulfur
components. The light emitted from the chemical reaction is then transmitted using the
fiber cable from the oven assembly to the electronics module. The PMT electronics
module consists of a 394 nm filter, a photomultiplier tube , and all the necessary
electronics to digitize the signal. The digital signal is then transmitted to the main central
processing unit (CPU) using CAN bus.
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Figure 1-5: µFPD burner - front view
A. µFPD burner
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Figure 1-6: µFPD burner - back view
A. µFPD burner
B. Fiber cable
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Figure 1-7: µFPD burner - side view
A. µFPD burner and cable
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