Thermo 42i User manual

Model 42i
Low Source
Instruction Manual
Chemiluminescence NO-NO2-NOxAnalyzer
Part number 102031-00
30May2006

© 2005 Thermo Electron Corporation. All rights reserved.
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your local sales representative for details.

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WEEE Compliance
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Electrical & Electronic Equipment (WEEE) Directive 2002/96/EC. It is
marked with the following symbol:
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companies in each EU Member State, and this product should be disposed
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Thermo Electron Corporation Model 42iLow Source Instruction Manual v
Contents
Chapter 1 Introduction......................................................................................1-1
Principle of Operation ............................................................1-2
Specifications ..........................................................................1-3
Chapter 2 Installation .......................................................................................2-1
Lifting.....................................................................................2-1
Unpacking and Inspection ......................................................2-1
Setup Procedure......................................................................2-3
Startup ....................................................................................2-5
Chapter 3 Operation ..........................................................................................3-1
Display....................................................................................3-2
Pushbuttons............................................................................3-3
Soft Keys..............................................................................3-4
Software Overview ..................................................................3-4
Power-Up Screen .................................................................3-6
Run Screen...........................................................................3-6
Main Menu..........................................................................3-7
Range Menu ...........................................................................3-8
Single Range Mode ..............................................................3-8
Dual Range Mode..............................................................3-10
Auto Range Mode..............................................................3-11
Gas Units...........................................................................3-14
NO, NO2, and NOxRanges..............................................3-14
Set Custom Ranges ............................................................3-16
Averaging Time.....................................................................3-17
Calibration Factors Menu .....................................................3-18
NO and NOxBackgrounds................................................3-19
NO, NO2, and NOxCoefficients ......................................3-21
Calibration Pressure ...........................................................3-22
Calibration Menu .................................................................3-23
Calibrate NO and NOxBackground..................................3-24
Calibrate NO, NO2, and NOxCoefficients .......................3-25
Calibrate Pressure...............................................................3-26
Zero/Span Check ...............................................................3-26

Contents
vi Model 42iLow Source Instruction Manual Thermo Electron Corporation
Instrument Controls Menu ...................................................3-30
Ozonator............................................................................3-30
PMT Supply ......................................................................3-31
Auto/Manual Mode ...........................................................3-31
Datalogging Settings ..........................................................3-32
Communication Settings....................................................3-42
I/O Configuration..............................................................3-50
Temperature Compensation...............................................3-62
Pressure Compensation ......................................................3-63
Screen Contrast..................................................................3-64
Service Mode .....................................................................3-64
Date/Time .........................................................................3-65
Diagnostics Menu .................................................................3-65
Program Version ................................................................3-66
Voltages .............................................................................3-66
Temperatures .....................................................................3-68
Pressure..............................................................................3-68
Flow...................................................................................3-68
Analog Input Readings.......................................................3-69
Analog Input Voltages........................................................3-69
Digital Inputs.....................................................................3-70
Relay States ........................................................................3-70
Test Analog Outputs..........................................................3-70
Instrument Configuration..................................................3-72
Contact Information..........................................................3-72
Alarms Menu ........................................................................3-73
Internal Temperature .........................................................3-74
Chamber Temperature.......................................................3-75
Cooler Temperature...........................................................3-76
Converter Temperature......................................................3-77
Pressure..............................................................................3-78
Ozonator Flow...................................................................3-79
Zero and Span Check.........................................................3-79
Zero and Span Auto Calibration ........................................3-80
NO, NO2, and NOxConcentration ..................................3-80

Contents
Thermo Electron Corporation Model 42iLow Source Instruction Manual vii
Service Menu ........................................................................3-82
PMT Voltage Adjustment..................................................3-83
Range Mode Select.............................................................3-83
Converter Set Temperature................................................3-84
Pressure Calibration ...........................................................3-84
Input Board Calibration.....................................................3-87
Temperature Calibration....................................................3-89
Analog Output Calibration ................................................3-90
Analog Input Calibration ...................................................3-92
Ozonator Safety .................................................................3-94
Extended Ranges................................................................3-94
Dilution Ratio....................................................................3-95
Display Pixel Test ..............................................................3-95
Restore User Defaults.........................................................3-96
Password ...............................................................................3-97
Set Password ......................................................................3-97
Lock Instrument ................................................................3-98
Change Password ...............................................................3-98
Remove Password...............................................................3-99
Unlock Instrument ............................................................3-99
Chapter 4 Calibration........................................................................................4-1
Equipment Required...............................................................4-1
Pre-Calibration .......................................................................4-1
Calibration..............................................................................4-2
Connecting the GPT Apparatus...........................................4-3
Dynamic Parameter Specifications for Gas Phase Titrator....4-4
Adjusting Instrument Gain ..................................................4-6
Preparing NO, NOx, and NO2Calibration Curves .............4-9
Calibration in Dual Range and Auto Range Mode................4-12
Calibrate Low NO .............................................................4-13
Calibrate Low NOx............................................................4-13
Calibrate Low NO2............................................................4-14
Calibrate High NO............................................................4-15
Calibrate High NOx..........................................................4-15
Calibrate High NO2..........................................................4-16
Zero and Span Check............................................................4-16
Chapter 5 Preventive Maintenance ...............................................................5-1
Safety Precautions ...................................................................5-1
Replacement Parts...................................................................5-2
Cleaning the Outside Case......................................................5-2
Ozonator Air Feed Drying Column Replacement ...................5-2
Capillaries Inspection and Replacement ..................................5-2

Contents
viii Model 42iLow Source Instruction Manual Thermo Electron Corporation
Thermoelectric Cooler Fins Inspection and Cleaning..............5-4
Fan Filters Inspection and Cleaning........................................5-4
Pump Rebuilding....................................................................5-5
Chapter 6 Troubleshooting.............................................................................. 6-1
Safety Precautions ...................................................................6-1
Troubleshooting Guides..........................................................6-2
Board-Level Connection Diagrams .........................................6-6
Connector Pin Descriptions....................................................6-8
Service Locations...................................................................6-22
Chapter 7 Servicing.......................................................................................... 7-1
Safety Precautions ...................................................................7-3
Firmware Updates...................................................................7-5
Replacement Parts List............................................................7-5
Cable List................................................................................7-6
Removing the Measurement Bench and
Lowering the Partition Panel...................................................7-8
Pump Replacement...............................................................7-11
Fan Replacement...................................................................7-12
PMT Cooler and Reaction Chamber Assembly Replacement 7-13
Photomultiplier Tube Replacement ......................................7-15
PMT High Voltage Power Supply Replacement ...................7-16
PMT Voltage Adjustment.....................................................7-18
Reaction Chamber Cleaning or Removal ..............................7-19
NO2-to-NO Converter Replacement....................................7-21
Solenoid Valve Replacement .................................................7-23
Ozonator Assembly Replacement ..........................................7-24
Ozonator Transformer Replacement .....................................7-26
Input Board Replacement .....................................................7-26
Input Board Calibration........................................................7-28
DC Power Supply Replacement ............................................7-29
Analog Output Testing .........................................................7-30
Analog Output Adjustment...................................................7-32
Pressure Transducer Assembly Replacement..........................7-33
Pressure Transducer Calibration ...........................................7-35
Temperature Control Board Replacement.............................7-37
Ambient Temperature Calibration ........................................7-37
Fuse Replacement .................................................................7-39
Scrubber Replacement...........................................................7-39
I/O Expansion Board (Optional) Replacement .....................7-40
Digital Output Board Replacement.......................................7-42
Motherboard Replacement....................................................7-42
Measurement Interface Board Replacement ..........................7-43

Contents
Thermo Electron Corporation Model 42iLow Source Instruction Manual ix
Front Panel Board Replacement............................................7-45
LCD Module Replacement ...................................................7-46
Service Locations...................................................................7-47
Chapter 8 System Description.........................................................................8-1
Hardware ................................................................................8-1
NO2-to-NO Converter...........................................................8-2
Mode Solenoid.....................................................................8-2
Reaction Chamber ...............................................................8-2
Optical Filter .......................................................................8-3
Pressure Transducer .............................................................8-3
Ozonator.................................................................................8-3
Ozonator Flow Switch .........................................................8-3
Photomultiplier Tube .............................................................8-3
Photomultiplier Tube Cooler..................................................8-3
Pump ......................................................................................8-3
Sample Capillary..................................................................8-3
Dry Air Capillary .................................................................8-4
Ammonia Scrubber .................................................................8-4
Software..................................................................................8-4
Instrument Control..............................................................8-4
Monitoring Signals...............................................................8-4
Measurement Calculations ...................................................8-5
Output Communication......................................................8-5
Electronics ..............................................................................8-6
Motherboard........................................................................8-6
Measurement Interface Board ..............................................8-7
Pressure Sensor Assembly .....................................................8-7
Temperature Control Board.................................................8-8
PMT Power Supply Assembly..............................................8-8
Input Board Assembly..........................................................8-8
Digital Output Board...........................................................8-8
I/O Expansion Board (Optional) .........................................8-9
Front Panel Connector Board ..............................................8-9
I/O Components ....................................................................8-9
Analog Voltage Outputs.......................................................8-9
Analog Current Outputs (Optional) ..................................8-10
Analog Voltage Inputs (Optional)......................................8-10
Digital Relay Outputs ........................................................8-10
Digital Inputs.....................................................................8-11
Serial Ports.........................................................................8-11
RS-232 Connection ...........................................................8-11
RS-485 Connection ...........................................................8-12
Ethernet Connection..........................................................8-12
External Accessory Connector ............................................8-12

Contents
xModel 42iLow Source Instruction Manual Thermo Electron Corporation
Chapter 9 Optional Equipment........................................................................ 9-1
Internal Zero/Span and Sample Valves....................................9-1
Permeation Dryer Assembly ....................................................9-2
Teflon Particulate Filter ..........................................................9-2
Ozone Particulate Filter ..........................................................9-2
NO2-to-NO Converters..........................................................9-3
I/O Expansion Board Assembly...............................................9-3
Terminal Block and Cable Kits ...............................................9-3
Mounting Options..................................................................9-4
Appendix A Warranty............................................................................................ A-1
Appendix B C-Link Protocol Commands............................................................ B-1
Instrument Identification Number......................................... B-2
Commands ............................................................................ B-2
Measurements........................................................................ B-9
Alarms.................................................................................. B-12
Diagnostics .......................................................................... B-16
Datalogging ......................................................................... B-16
Calibration........................................................................... B-23
Keys/Display........................................................................ B-26
Measurement Configuration ................................................ B-28
Hardware Configuration...................................................... B-32
Communications Configuration .......................................... B-35
I/O Configuration................................................................ B-39
Record Layout Definition .................................................... B-44
Format Specifier for ASCII Responses............................... B-44
Format Specifier for Binary Responses .............................. B-44
Format Specifier for Front-Panel Layout .......................... B-45
Appendix C MODBUS Protocol ........................................................................... C-1
Serial Communication Parameters .........................................C-2
TCP Communication Parameters ..........................................C-2
Application Data Unit Definition ..........................................C-2
Function Codes......................................................................C-3
MODBUS Commands Supported.........................................C-8
Appendix D Geysitech (Bayern-Hessen) Protocol...........................................D-1

Figures
Thermo Electron Corporation Model 42iLow Source Instruction Manual xi
Figures
Model 42i Low Source Flow Schematic ...................................1-3
Remove the Packing Material ..................................................2-2
Remove the Shipping Screws ...................................................2-2
Model 42i Low Source Rear Panel ...........................................2-4
Atmospheric Dump Bypass Plumbing .....................................2-4
42i Low Source Front Panel Display .......................................3-2
Front Panel Pushbuttons .........................................................3-3
Flowchart of Menu-Driven Software .......................................3-5
Pin-Out of Rear Panel Connector in Single Range Mode ........3-9
Pin-Out of Rear Panel Connector in Dual Range Mode ........3-10
Analog Output in Auto Range Mode ....................................3-12
Pin-Out of Rear Panel Connector in Auto Range Mode ........3-13
GPT System ............................................................................4-4
Inspecting and Replacing the Capillaries .................................5-3
Rebuilding the Pump ..............................................................5-6
Board-Level Connection Diagram - Common Electronics .......6-6
Board-Level Connection Diagram - Measurement System ......6-7
Properly Grounded Antistatic Wrist Strap ...............................7-4
Component Layout .................................................................7-7
Remove the Measurement Bench Screws .................................7-8
Slide Out the Measurement Bench ..........................................7-9
Lower the Partition Panel ......................................................7-10
Replacing the Pump ..............................................................7-12
Replacing a Fan .....................................................................7-13
PMT Cooler and Reaction Chamber .....................................7-14
Replacing the PMT ...............................................................7-16
Replacing the PMT HVPS ....................................................7-17
Cleaning or Removing the Reaction Chamber ......................7-20
NO2-to-NO Moly Converter Assembly ................................7-22
Replacing the Solenoid Valve ................................................7-24
Replacing the Ozonator Assembly .........................................7-25
Replacing the Input Board ....................................................7-27
Replacing the DC Power Supply ...........................................7-30
Rear Panel Analog Voltage Output Pins ................................7-31
Replacing the Pressure Transducer ........................................7-34
Replacing the Scrubber ..........................................................7-40
Replacing the I/O Expansion Board (Optional) ....................7-41
Rear Panel Board Connectors ................................................7-41
Replacing the Measurement Interface Board .........................7-44
Replacing the Front Panel Board and the LCD Module ........7-45
Hardware Components ...........................................................8-2
Flow Diagram, Zero/Span Option ..........................................9-2

Figures
xii Model 42iLow Source Instruction Manual Thermo Electron Corporation
Rack Mount Option Assembly ................................................9-4
Bench Mounting .....................................................................9-5
EIA Rack Mounting ................................................................9-6
Retrofit Rack Mounting ..........................................................9-7
Flag Status ............................................................................ B-12

Tables
Thermo Electron Corporation Model 42iLow Source Instruction Manual xiii
Tables
Model 42i Low Source Specifications ....................................................... 1-3
Front Panel Pushbuttons .......................................................................... 3-3
Default Analog Outputs in Single Range Mode ....................................... 3-9
Default Analog Outputs in Dual Range Mode ....................................... 3-11
Default Analog Outputs in Auto Range Mode ....................................... 3-13
Standard Ranges ..................................................................................... 3-15
Extended Ranges .................................................................................... 3-16
Analog Output Zero to Full-Scale Table ................................................ 3-56
Signal Type Group Choices ................................................................... 3-57
Troubleshooting - General Guide ............................................................ 6-2
Troubleshooting - Alarm Messages ........................................................... 6-3
Motherboard Connector Pin Descriptions ............................................... 6-8
Measurement Interface Board Connector Pin Descriptions .................... 6-13
Front Panel Board Connector Pin Diagram ........................................... 6-16
I/O Expansion Board (Optional) Connector Pin Descriptions ............... 6-18
Digital Output Board Connector Pin Descriptions ................................ 6-19
Input Board Connector Pin Descriptions ............................................... 6-20
Temperature Control Board Connector Pin Descriptions ...................... 6-21
Model 42i Low Source Replacement Parts ............................................... 7-5
Model 42i Low Source Cables .................................................................. 7-6
Analog Output Channels and Rear Panel Pin Connections .................... 7-31
RS-232 DB Connector Pin Configurations ............................................ 8-12
RS-485 DB Connector Pin Configuration ............................................. 8-12
Mounting Options ................................................................................... 9-4
C-Link Protocol Commands ....................................................................B-3
Averaging Times ......................................................................................B-9
Alarm Trigger Values .............................................................................B-15
Record Output Formats .........................................................................B-20
Stream Time Values ...............................................................................B-23
Standard Ranges .....................................................................................B-29
Extended Ranges ....................................................................................B-29
Contrast Levels .......................................................................................B-32
Reply Termination Formats ...................................................................B-38
Analog Current Output Range Values ...................................................B-40
Analog Voltage Output Range Values ....................................................B-40
Default Output Assignment ...................................................................B-42
Read Coils for 42i Low Source .................................................................C-8
Read Registers for 42i Low Source ...........................................................C-9
Write Coils for 42i Low Source ..............................................................C-10
Operating Status for Model 42i Low Source ........................................... D-7
Error Status for Model 42i Low Source ................................................... D-7

Tables
xiv Model 42iLow Source Instruction Manual Thermo Electron Corporation

Thermo Electron Corporation Model 42iLow Source Instruction Manual xv
About This Manual
This manual provides information about operating, maintaining, and
servicing the analyzer. It also contains important alerts to ensure safe
operation and prevent equipment damage. The manual is organized into the
following chapters and appendices to provide direct access to specific
operation and service information:
• Chapter 1 “Introduction” provides an overview of product features,
describes the principles of operation, and lists the specifications.
• Chapter 2 “Installation” describes how to unpack, setup, and startup the
analyzer.
• Chapter 3 “Operation” describes the front panel display, the front panel
pushbuttons, and the menu-driven software.
• Chapter 4 “Calibration” provides the procedures for calibrating the
analyzer and describes the required equipment.
• Chapter 5 “Preventive Maintenance” provides maintenance procedures
to ensure reliable and consistent instrument operation.
• Chapter 6 “Troubleshooting” presents guidelines for diagnosing analyzer
failures, isolating faults, and includes recommended actions for restoring
proper operation.
• Chapter 7 “Servicing” presents safety alerts for technicians working on
the analyzer, step-by-step instructions for repairing and replacing
components, and a replacement parts list. It also includes contact
information for product support and technical information.
• Chapter 8 “System Description” describes the function and location of
the system components, provides an overview of the software structure,
and includes a description of the system electronics and input/output
connections.
• Chapter 9 “Optional Equipment” describes the optional equipment that
can be used with this analyzer.
• Appendix A “Warranty” provides a copy of the warranty statement.

Preface
Safety
xvi Model 42iLow Source Instruction Manual Thermo Electron Corporation
• Appendix B “C-Link Protocol Commands” provides a description of the
C-Link protocol commands that can be used to remotely control an
analyzer using a host device such as a PC or a datalogger.
• Appendix C “MODBUS Protocol” provides a description of the
MODBUS Protocol Interface and is supported both over RS-232/485
(RTU protocol) as well as TCP/IP over Ethernet.
Safety Review the following safety information carefully before using the analyzer.
This manual provides specific information on how to operate the analyzer,
however if the analyzer is used in a manner not specified by the
manufacturer, the protection provided by the equipment may be impaired.
Safety and Equipment
Damage Alerts
This manual contains important information to alert you to potential safety
hazards and risks of equipment damage. Refer to the following types of
alerts you may see and the actual alerts that appear in this manual.
Safety and Equipment Damage Alert Descriptions
Alert Description
DANGER A hazard is present that will result in death or serious
personal injury if the warning is ignored. 
WARNING A hazard is present or an unsafe practice can result in
serious personal injury if the warning is ignored. 
CAUTION The hazard or unsafe practice could result in minor to
moderate personal injury if the warning is ignored. 
Equipment Damage The hazard or unsafe practice could result in property
damage if the warning is ignored. 

Preface
Safety
Thermo Electron Corporation Model 42iLow Source Instruction Manual xvii
Safety and Equipment Damage Alerts in this Manual
Alert Description
WARNING If the equipment is operated in a manner not specified by
the manufacturer, the protection provided by the
equipment may be impaired. 
The service procedures in this manual are restricted to
qualified service personnel only. 
The Model 42iLow Source is supplied with a three-wire
grounding cord. Under no circumstances should this
grounding system be defeated. 
CAUTION If the LCD panel breaks, do not to let the liquid crystal
contact your skin or clothes. If the liquid crystal contacts
your skin or clothes, wash it off immediately using soap
and water. 
Avoid contact with converter heated components. Allow
converter to cool to room temperature before handling
converter components. 
Equipment Damage Do not attempt to lift the analyzer by the cover or other
external fittings. 
This adjustment should only be performed by an
instrument service technician. 
Some internal components can be damaged by small
amounts of static electricity. A properly grounded
antistatic wrist strap must be worn while handling any
internal component. 
Handle all printed circuit boards by the edges only. 
Do not point the photomultiplier tube at a light source.
This can permanently damage the tube. 
Do not remove the panel or frame from the LCD module.

The LCD module polarizing plate is very fragile, handle it
carefully. 
Do not wipe the LCD module polarizing plate with a dry
cloth, it may easily scratch the plate. 
Do not use alcohol, acetone, MEK or other Ketone based
or aromatic solvents to clean the module, use a soft
cloth moistened with a naphtha cleaning solvent. 
Do not place the LCD module near organic solvents or
corrosive gases. 
Do not shake or jolt the LCD module. 

Preface
Where to Get Help
Thermo Electron Corporation Model 42iLow Source Instruction Manual xviii
WEEE Symbol The following symbol and description identify the WEEE marking used on
the instrument and in the associated documentation.
Where to Get Help Service is available from exclusive distributors worldwide. Contact one of
the phone numbers below for product support and technical information.
866-282-0430 Toll Free
508-520-0430 International
Symbol Description
Marking of electrical and electronic equipment which applies to
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after 13 August 2005.

Thermo Electron Corporation 42iLow Source Instruction Manual 1-1
Chapter 1 Introduction
The Model 42i Low Source Chemiluminescence NO-NO2-NOxAnalyzer
combines proven detection technology, easy to use menu-driven software,
and advanced diagnostics to offer unsurpassed flexibility and reliability. The
Model 42iLow Source has the following features:
• 320 x 240 graphics display
• Menu-driven software
• Field programmable ranges
• User-selectable single/dual/auto range modes
• Multiple user-defined analog outputs
• Analog input options
• High sensitivity
• Fast response time
• Linearity through all ranges
• Independent NO-NO2-NOxranges
• Replaceable NO2converter cartridge
• User-selectable digital input/output capabilities
• Standard communications features include RS232/485 and Ethernet
• C-Link, MODBUS, and streaming data protocols
For details of the analyzer’s principle of operation and product
specifications, see the following topics:
•“Principle of Operation” on page 1-2 describes the principles by which
your analyzer operates.

Introduction
Principle of Operation
1-2 42iLow Source Instruction Manual Thermo Electron Corporation
•“Specifications” on page 1-3 is a list of the analyzer’s performance
specifications.
Thermo Electron is pleased to supply this chemiluminescence
NO-NO2-NOxanalyzer. We are committed to the manufacture of
instruments exhibiting high standards of quality, performance, and
workmanship. Service personnel are available for assistance with any
questions or problems that may arise in the use of this analyzer. For more
information on servicing, see Chapter 7, “Servicing”.
Principle of Operation The Model 42i Low Source operates on the principle that nitric oxide (NO)
and ozone (O3) react to produce a characteristic luminescence with an
intensity linearly proportional to the NO concentration. Infrared light
emission results when electronically excited NO2molecules decay to lower
energy states. Specifically,
Nitrogen dioxide (NO2) must first be transformed into NO before it can be
measured using the chemiluminescent reaction. NO2is converted to NO by
a stainless steel NO2-to-NO converter heated to about 625 °C (the optional
molybdenum converter is heated to 325 °C).
The ambient air sample is drawn into the Model 42iLow Source through
the sample bulkhead, as shown in Figure 1-1. The sample flows through a
capillary, and then to the mode solenoid valve. The solenoid valve routes the
sample either straight to the reaction chamber (NO mode) or through the
NO2-to-NO converter and then to the reaction chamber (NOxmode). A
flow sensor prior to the reaction chamber measures the sample flow.
Dry air enters the Model 42iLow Source through the dry air bulkhead,
passes through a flow switch, and then through a silent discharge ozonator.
The ozonator generates the ozone needed for the chemiluminescent
reaction. At the reaction chamber, the ozone reacts with the NO in the
sample to produce excited NO2molecules. A photomultiplier tube (PMT)
housed in a thermoelectric cooler detects the luminescence generated during
this reaction. From the reaction chamber, the exhaust travels through the
ozone (O3) converter to the pump, and is released through the vent.
The NO and NOxconcentrations calculated in the NO and NOxmodes
are stored in memory. The difference between the concentrations is used to
calculate the NO2concentration. The Model 42iLow Source outputs NO,
υ hONOONO 223 ++→+