Industrial Scientific iTrans 77023554 User manual

FIXED POINT
SINGLE OR DUAL GAS MONITOR WITH
DUAL ANALOG OUTPUTS
Installation Operation Wiring Troubleshooting
Part Number: 77023554
Version: 10
Release Date: October 27, 2009

iTrans Fixed Point Single/Dual Gas Monitor
ii INDUSTRIAL SCIENTIFIC (P/N: 77023554)
is a trademark of Industrial Scientific Corporation.
ModBusis a registered trademark of Schneider Automation Inc.
ModBusprotocolis a trademark of Schneider Automation Inc.
All other trademarks and registered trademarks are the property of their respective
owners.
Industrial Scientific Corporation Phone: [phone]
1001 Oakdale Road Toll Free: 1-800-DETECTS (338-3287)
Oakdale, PA 15071-1500 Fax: [phone]
USA Service: 1-888-788-4353
Web: www.indsci.com
Although every effort is made to ensure accuracy, the specifications of this product
and the content herein are subject to change without notice.
© 2008 Industrial Scientific. All rights reserved.

iTrans Fixed Point Single/Dual Gas Monitor
(P/N: 77023554) INDUSTRIAL SCIENTIFIC iii
Warnings and Cautionary Statements
CAUTION: Failure to perform certain procedures or note certain conditions may
impair the performance of the monitor. For maximum safety and performance,
please read and follow the procedures and conditions outlined below.
Oxygen deficient atmospheres may cause combustible gas readings that use
catalytic LEL sensors to be lower than actual concentrations.
Oxygen enriched atmospheres may cause combustible gas readings that use
catalytic LEL sensors to be higher than actual concentrations.
Calibrate the catalytic combustible gas sensor after each incident where the
combustible gas content causes the instrument to enter in the OVER-RANGE
alarm condition.
Silicone compound vapors may affect the catalytic combustible gas sensor and
cause readings of combustible gas to be lower than actual gas concentrations. If
the sensor has been used in an area where silicone vapors were present, always
calibrate the instrument before continued use to ensure accurate measurements.
Sensor openings must be kept clean. Obstruction of the sensor openings may
cause readings to be lower than actual gas concentrations.
Sudden changes in atmospheric pressure may cause temporary fluctuations in
the oxygen readings.
Alarms relays are non-latching.
When connecting 4-20 mA outputs to inductive loads, Industrial Scientific
Corporation recommends using an isolation barrier in line with the 4-20 mA
signal.
Interior grounding terminal is to be used for grounding, the exterior terminal is
only to be used for bonding
CALIBRATION ALERT: Gas detection instruments are potential life-saving
devices. Recognizing this fact, calibration for the toxic and catalytic LEL sensors
should be at least at quarterly intervals, while the infrared sensor should be
calibrated on an annual basis with function test every 6 months.
Further, Industrial Scientific Corporation recommends prudent testing and/or
includes calibration after a gas alarm. All calibration service to sensors should be
recorded and accessible.

iTrans Fixed Point Single/Dual Gas Monitor
iv INDUSTRIAL SCIENTIFIC (P/N: 77023554)
CAUTION: For safety reasons, this equipment must be operated and serviced by
qualified personnel only.
Mission Statement
Design – Manufacture – Sell:
Highest quality products for the preservation of life and property
Provide:
Best Customer Service
In practical terms, that means developing both portable instruments and fixed-point
systems for detecting, measuring and monitoring a wide variety of gases, including
toxic and combustible gases, as well as oxygen.
From research and development through final manufacturing, we never forget that
human lives depend on what we do. That workers all over the world enter confined
spaces, face the risk of asphyxiation, poisoning or explosion, and depend on our
instruments to ensure their safety. That's why every one of our products is designed
and manufactured with just one question in mind: “Would you bet your life on
it?”

iTrans Fixed Point Single/Dual Gas Monitor Table of Contents
(P/N: 77023554) INDUSTRIAL SCIENTIFIC v
Table of Contents
CHAPTER 1: INTRODUCTION
1.1. Overview of the Gas Monitor ............................................................................1-1
1.2. Specifications .........................................................................................................................1-1
1.3. Agency Approvals - CSA.......................................................................................................1-3
1.4. Special Instructions for Safe Use (EU) ..................................................................................1-4
CHAPTER 2: HARDWARE OVERVIEW
2.1. Main Electronics Unit (Housing) ...........................................................................................2-1
2.2. Sensor.....................................................................................................................................2-2
2.3. Display....................................................................................................................................2-3
2.4. Inputs – Intrusive and Non-Intrusive......................................................................................2-4
2.5. Electronics Modules...............................................................................................................2-5
CHAPTER 3: INSTALLATION
3.1. Introduction ............................................................................................................................3-1
3.2. Installation Considerations.....................................................................................................3-1
3.3. Wall Mounting .......................................................................................................................3-1
3.4. Column Mounting ..................................................................................................................3-1
CHAPTER 4: SYSTEM WIRING
4.1. Introduction ............................................................................................................................4-1
4.2. Wiring Preparation .................................................................................................................4-1
4.3. Alarm Relay Wiring (J1, J5, and J6)......................................................................................4-2
4.4. Power and Output Wiring (J1) ...............................................................................................4-4
4.5. Sensor Wiring (J3)..................................................................................................................4-5
4.6. Digital ModBus RTU Interface Wiring (J2) ........................................................................4-14
4.6.1. ModBus Interface Wiring Overview........................................................................4-14
4.6.2. Setting the ModBus Address on the ....................................................4-14
4.6.3. Setting the ModBus Address for Stand-Alone Sensors...........................................4-15
4.7. Wiring Conclusion................................................................................................................4-16
CHAPTER 5: OPERATION
5.1. Initial Start-up.........................................................................................................................5-1
5.2. Warm-up Period .....................................................................................................................5-1
5.3. Normal Operating Mode.........................................................................................................5-2
5.4. Programming Mode Overview...............................................................................................5-3
5.5. Programming Mode – Non-intrusive Operation.....................................................................5-5
5.5.1. Introduction................................................................................................................5-5
5.5.2. Sensor Type ...............................................................................................................5-5
5.5.3. Zeroing.......................................................................................................................5-6
5.5.4. Calibration..................................................................................................................5-6
5.5.5. Changing Span Gas Concentration............................................................................5-8
5.5.6. Sensor Span Reserve..................................................................................................5-9
5.6. Programming Mode – Push Button Operation.......................................................................5-9
5.6.1. Introduction................................................................................................................5-9
5.6.2. Entering Programming Mode and Selecting a Channel.............................................5-9
5.6.3. Set Low Alarm.........................................................................................................5-10

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5.6.4. Set High Alarm........................................................................................................5-10
5.6.5. 4-20 mA Analog Output Range...............................................................................5-11
5.6.6. Set System Time – Minute.......................................................................................5-11
5.6.7. Set System Time – Hour..........................................................................................5-12
5.6.8. Set System Time – Date...........................................................................................5-12
5.6.9. Set System Time – Month........................................................................................5-13
5.6.10. Set System Time – Year..........................................................................................5-13
5.6.11. Zeroing ....................................................................................................................5-13
5.6.12. Calibration...............................................................................................................5-14
5.6.13. Changing Span Gas Concentration..........................................................................5-15
5.6.14. Sensor Span Reserve ...............................................................................................5-16
5.7. Summary of Displayed Function Codes...............................................................................5-17
5.8. Special Notes on Using Broadband Infrared (BBIR) Sensors..............................................5-17
CHAPTER 6: MODBUS INTERFACE
6.1. Introduction ............................................................................................................................6-1
6.2. Sample Gas Reading via ModBus Network...........................................................................6-2
6.3. Special Notes on Using Broadband Infrared (BBIR) Sensors................................................6-2
6.4. ModBus Register List.............................................................................................................6-3
6.5. Setting the ModBus Address on the ...................................................................6-7
6.6. Setting the ModBus Address for Stand-Alone Sensors..........................................................6-8
6.7. ModBus Resources...............................................................................................................6-10
6.8. Termination ..........................................................................................................................6-10
CHAPTER 7: MAINTENANCE
7.1. Introduction ............................................................................................................................7-1
7.2. Sensor Replacement ...............................................................................................................7-2
7.3. Zero and Calibration...............................................................................................................7-2
CHAPTER 8: TROUBLESHOOTING
8.1. Introduction ............................................................................................................................8-1
8.2. Diagnosing Common Problems..............................................................................................8-1
8.3. Fault Codes.............................................................................................................................8-2
8.4. Function Codes.......................................................................................................................8-3
8.5. Special Notes on Using Broadband Infrared (BBIR) Sensors................................................8-4
CHAPTER 9: WARRANTY
9.1. Warranty.................................................................................................................................9-1
9.2. Limitation of Liability............................................................................................................9-1
APPENDIX A: ACRONYMS AND ABBREVIATIONS
APPENDIX B: DECIMAL, BINARY, AND HEXADECIMAL EQUIVALENTS
APPENDIX C: ORDERING MATRIX
APPENDIX D: FACTORY DEFAULT SETTINGS
APPENDIX E: EC DECLARATION OF CONFORMITY CERTIFICATE
INDEX 

iTrans Fixed Point Single/Dual Gas Monitor List of Figures
(P/N: 77023554) INDUSTRIAL SCIENTIFIC vii
List of Figures
CHAPTER 1: INTRODUCTION
Figure 1-1. Typical Gas Monitor with Single Gas Sensor ............................................1-1
CHAPTER 2: HARDWARE OVERVIEW
Figure 2-1. Details of a Single-Gas Gas Monitor..........................................................2-1
Figure 2-2. The Display (Dual-Gas Monitor Shown)....................................................2-3
Figure 2-3. Locations of Input Keys and Reed Switches ..............................................2-4
Figure 2-4. Electronics Module for (Main Unit)...........................................................2-5
Figure 2-5. Electronics Board for Sensor......................................................................2-6
CHAPTER 3: INSTALLATION
Figure 3-1. Mounting the Gas Monitor on a Wall.........................................................3-2
Figure 3-2. Mounting the Gas Monitor on a Column Using U-Bolts............................3-2
CHAPTER 4: SYSTEM WIRING
Figure 4-1. High and Low Alarm Relay Connectors J6 and J5.........................................................4-2
Figure 4-2. Electronics Module for (Main Unit)...........................................................4-3
Figure 4-3. Fault Alarm Relay Connector J1 on the ......................................................4-4
Figure 4-4. Power and Signal Connector J1 on the .......................................................4-4
Figure 4-5. Sensor Connector J3 on the ........................................................................4-5
Figure 4-6. Wiring Diagram for a Single On-board Sensor...............................................................4-6
Figure 4-7. Wiring Diagram for a Remote Sensor (Stand Alone) .....................................................4-7
Figure 4-8. Electronics Module for (Remote Unit).......................................................4-8
Figure 4-9. Wiring Diagram for Dual On-board Sensors ..................................................................4-9
Figure 4-10. Wiring Remote Sensors Back to .............................................................4-10
Figure 4-11. Wiring One Remote Sensor and One On-Board Sensor .............................................4-11
Figure 4-11. Wiring One Remote Sensor and One On-Board Sensor (Continued).........................4-12
Figure 4-12. Wiring Dual Remote Sensors......................................................................................4-13
Figure 4-13. Wiring Diagram for the ModBus Interface.................................................................4-14
Figure 4-14. Switch Bank for Setting ModBus Slave Address........................................................4-14
Figure 4-15. Setting the ModBus Address (Example Address of 240 Decimal).............................4-15
Figure 4-16. Location of Address DIP Switch on Sensor Electronics Module ...............................4-16
Figure 4-17. Setting the ModBus Address for a Stand-Alone Sensor .............................................4-16
CHAPTER 5: OPERATION
Figure 5-1. Sample Fault Code Display.............................................................................................5-1
Figure 5-2. Sample Dual-Sensor Display ..........................................................................................5-2
Figure 5-3. Sample Low and High Alarm Displays...........................................................................5-2
Figure 5-4. Locations of Reed Switches and Push Buttons................................................................5-3
Figure 5-5. Components of the Display.............................................................................................5-4
Figure 5-6. Programming Mode Display Showing Flashing Decimal Points....................................5-4
Figure 5-7. Sample Display Entering Non-Intrusive Mode...............................................................5-5
Figure 5-8. Sample Zeroing Display..................................................................................................5-6
Figure 5-9. Sample Calibration Display ............................................................................................5-6
Figure 5-10. Sample Zeroing Display................................................................................................5-7

List of Figures iTrans Fixed Point Single/Dual Gas Monitor
viii INDUSTRIAL SCIENTIFIC (P/N: 77023554)
Figure 5-11. Apply CalGas Display...................................................................................................5-7
Figure 5-12. Sample Span Gas Concentration Display......................................................................5-8
Figure 5-13. Flashing Status Bit ........................................................................................................5-8
Figure 5-14. Sample Span Reserve Display.......................................................................................5-9
Figure 5-15. Sample Channel Selection Display...............................................................................5-9
Figure 5-16. Sample Low Alarm Setpoint Display..........................................................................5-10
Figure 5-17. Sample High Alarm Setpoint Display.........................................................................5-10
Figure 5-18. Changing the Analog Output Upper Value.................................................................5-11
Figure 5-19. Setting System Time (Minutes)...................................................................................5-11
Figure 5-20. Setting System Time (Hour) .......................................................................................5-12
Figure 5-21. Setting System Date....................................................................................................5-12
Figure 5-22. Setting System Month.................................................................................................5-13
Figure 5-23. Setting System Year....................................................................................................5-13
Figure 5-24. Sample Zeroing Display..............................................................................................5-14
Figure 5-25. Sample Calibration Display ........................................................................................5-14
Figure 5-26. Sample Zeroing Display..............................................................................................5-15
Figure 5-27. Sample Calibration Display ........................................................................................5-15
Figure 5-28. Sample Span Gas Concentration Display....................................................................5-15
Figure 5-29. Flashing Status Bit ......................................................................................................5-16
Figure 5-30. Sample Span Reserve Display.....................................................................................5-16
CHAPTER 6: MODBUS INTERFACE
Figure 6-1. Switch Bank for Setting ModBus Slave Address............................................................6-7
Figure 6-2. Setting the ModBus Address (Example Address of 240 Decimal).................................6-8
Figure 6-3. Location of Address DIP Switch on Sensor Electronics Module ...................................6-9
Figure 6-4. Setting the ModBus Address for a Stand-Alone Sensor.................................................6-9
Figure 6-5. Location of Jumpers......................................................................................................6-10


iTrans Fixed Point Single/Dual Gas Monitor List of Tables
(P/N: 77023554) INDUSTRIAL SCIENTIFIC ix
List of Tables
CHAPTER 1: INTRODUCTION
Table 1-1. Specifications for the Monitor ................................................................1-2
Table 1-2. Sensor Ranges .............................................................................................................1-3
CHAPTER 2: HARDWARE OVERVIEW
Table 2-1. Sensor Types and Ranges............................................................................................2-2
Table 2-2. Sensor Specifications...................................................................................................2-3
CHAPTER 5: OPERATION
Table 5-1. Fault Codes.......................................................................................................................5-2
Table 5-2. Function Codes...............................................................................................................5-17
CHAPTER 6: MODBUS INTERFACE
Table 6-1. ModBus Characteristics for the Gas Monitor ..............................................6-1
Table 6-2. ModBus Registers ............................................................................................................6-3
CHAPTER 8: TROUBLESHOOTING
Table 8-1. Common Problems...........................................................................................................8-1
Table 8-2. Fault Codes.......................................................................................................................8-2
Table 8-3. Function Codes.................................................................................................................8-3
APPENDIX A: ACRONYMS AND ABBREVIATIONS
Table A-1. Acronyms and Abbreviations.........................................................................................A-1
APPENDIX B: DECIMAL, BINARY, AND HEXADECIMAL EQUIVALENTS
Table B-1. Hexadecimal and Decimal Equivalents..........................................................................B-1
Table B-2. Decimal and Binary Equivalents ....................................................................................B-2
APPENDIX D: FACTORY DEFAULT SETTINGS
Table D-1. Factory Default Settings.................................................................................................D-1


List of Tables iTrans Fixed Point Single/Dual Gas Monitor
x INDUSTRIAL SCIENTIFIC (P/N: 77023554)

iTrans Fixed Point Single/Dual Gas Monitor Introduction
(P/N: 77023554) INDUSTRIAL SCIENTIFIC 1-1
INTRODUCTION
Chapter
1
1.1. Overview of the Gas Monitor
The fixed gas monitor is an
independent monitor capable of
displaying one or two gas
concentrations as well as sensor or
instrument specific diagnostics.
The comes standard with
independent 4-20 mA outputs for each
channel, making it ideal for interfacing
to control units. A digital ModBus
RTU interface is also available,
allowing the to interface to
digital control systems. The
is available with an optional relay
board, allowing the unit to directly
control external devices such as fans,
pumps, alarm horns, or warning lights.
Two of the relays can be programmed
for alarm activation, while the third
relay is a fault protection relay.
Figure 1-1. Typical Gas
Monitor with Single Gas Sensor
Calibration, changing span gas concentration, and checking the instrument’s
configuration are easily accomplished using the non-intrusive magnetic wand.
The is powered with a 24 VDC (12-28 VDC) power supply and provides
a 4-20 mA control signal for each sensor.
1.2. Specifications
Specifications for the gas monitor are listed in Table 1-1.

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Table 1-1. Specifications for the Monitor
Item Description
Enclosure Cast aluminum, poly-bonded coating or 316 stainless steel. Both are
explosion-proof, NEMA 4X, IP66 rated.
Dimensions 5.0 6.0 5.0 inches (127 153 129 mm)
Sensors Combustible Gases: Catalytic bead and/or Non-Dispersive Infrared
(NDIR)
Oxygen/Toxic Gases: Electrochemical diffusion
Input Voltage 12-28 VDC operating range (24 VDC typical), 350 mA (nominal)
Maximum current draw of 600 mA with 2 LEL sensors installed
Toxic Gas/Oxygen 150 mA @ 24 VDC (single gas)
Combustible Gases
(Catalytic) 175 ma @ 24 VDC, 0.6 A peak (single gas)
Combustible Gases
(Infrared) 150 ma @ 24 VDC, 0.6 A peak (single gas)
Input Current
(Max)
Combined
Catalytic/Infrared 280 ma @ 24 VDC (two gas)
Display Dual-channel split-screen LED display (4 digit, 7 segment arrangement
per channel) provides simultaneous display of one or two gases.
Digital
ModBus RTU: RS485 digital communication with
ModBus RTU software protocol system at 9600 baud.
Three- or four-wire system accommodates over 200
devices in bus configuration. Address selection through
on-board 8-position DIP switch. NOTE: ModBus is not
to be used for CSA C22.2 No. 152 compliance.
Signal
Outputs
Analog 4-20 mA (linear analog)
Quantity 3 alarm relays: Two user-programmable relays, SPST,
N.O.; plus one fault relay, SPST, N.C.
Alarm Relays Contact
Capacity 5A @ 30 VDC
5A @ 30 VAC
Temperature
Range -40º C ~ +75º C (-40º F ~ +167º F)
-20º C ~ +50º C (-4º F ~ +122º F) for BBIR only
Humidity
Range 10% - 90% RH (non-condensing), typical
Pressure Atmospheric pressure 10%

iTrans Fixed Point Single/Dual Gas Monitor Introduction
(P/N: 77023554) INDUSTRIAL SCIENTIFIC 1-3
Table 1-2. Sensor Ranges
Sensor Gas Range/Resolution
Combustible Gases LEL 0 -100% LEL in 1% increments
Hydrogen H20 - 999 ppm in 1 ppm increments
Oxygen O20 - 30.0% by vol. in 0.1% increments
Ammonia NH30 - 200 ppm in 1 ppm increments
Carbon Monoxide CO 0 - 999 ppm in 1 ppm increments
Carbon Monoxide/H2Null CO 0 - 999 ppm in 1 ppm increments
Hydrogen Sulfide H2S 0 - 500 ppm in 1 ppm increments
Sulfur Dioxide SO20.2 - 99.9 ppm in 0.1 ppm increments
Hydrogen Cyanide HCN 0.2 – 30.0 ppm in 0.1 ppm increments
Hydrogen Chloride HCl 0.2 - 30.0 ppm in 0.1 ppm increments
Phosphine PH30 - 1.00 ppm in 0.01 ppm increments
Nitrogen Dioxide NO20.2 - 99.9 ppm in 0.1 ppm increments
Nitric Oxide NO 0 - 999 ppm in 1 ppm increments
Chlorine Cl20.2 - 99.9 ppm in 0.1 ppm increments
Chlorine Dioxide ClO20.02 - 2.00 ppm in 0.01 ppm increments
1.3. Agency Approvals - CSA
The is certified by CSA, a NRTL laboratory, to the following US and
Canadian Standards.
UL Std No. 916-Energy Management Equipment
UL Std No. 1203-Explosion-Proof and Dust-Ignition-Proof
oElectrical Equipment for Use in Hazardous (Classified) Locations
UL Std No. 1604-Division 2 Hazardous Location Electrical Equipment
ISA S12.13 Part I-2000-Performance Requirements, Combustible Gas
Detectors
CSA Std C22.2 No.30-M1986-Explosion-Proof Enclosures for Use in
Class I Hazardous Locations
CSA Std C22.2 No.142-M1987-Process Control Equipment
CSA Std C22.2 No. 152-M1984-Combustible Gas Detection Instruments

Introduction iTrans Fixed Point Single/Dual Gas Monitor
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CSA Std C22.2 No. 213-M1987-Non-incendive Electrical Equipment for
Use in Class I, Division 2 Hazardous Locations
And is certified under the IECEx scheme to:
IECEx 60079-0 Electrical apparatus for potentially explosive atmospheres–
General requirements.
IECEx 60079-1: Electrical apparatus for potentially explosive atmospheres–
Flameproof enclosures ‘d’.
IECEx 60079-15: Electrical apparatus for explosive gas atmospheres. Type
of protection "n".
The complies with relevant provisions, per listed standards, of European
ATEX Directive 94/9/EC and EMC Directive 89/336/EEC, amended by Directives
92/31/EEC and 93/68/EEC, and is constructed with reference to published
standards of Directive 72/23/EEC, to eliminate electrical risks and fulfill 1.2.7 of
Annex II of Directive 94/9/EC.
EN 60079-0: Electrical apparatus for potentially explosive atmospheres –
General requirements.
EN 60079-1: Electrical apparatus for potentially explosive atmospheres –
Flameproof enclosures ‘d’.
EN 60079-15: Electrical apparatus for explosive gas atmospheres. Type of
protection “n”.
EN 50270: Electromagnetic compatibility - Electrical apparatus for the
detection and measurement of combustible gases, toxic gases or oxygen (for
Type 2 [Industrial] Apparatus).
The EC type examination certificate is KEMA 04 ATEX 2216X, with
marking code EEx d IIB+H2 T5; EEx nA II T5(Zone 2 sensors); -40ºC<Ta<75ºC,
and the LEL (Infrared) EC type examination certificate is DEMKO 02 ATEX
132278X, with marking code EEx d IIB+H2 T6. Equipment Group and Category is
II 2G and II 3G. Notified body responsible for production quality assurance is
SIRA, notified body No. 0518.
1.4. Special Instructions for Safe Use (EU)
Cable connection: The cable entry device shall be of a certified flameproof
type, suitable for the conditions of use and correctly installed.

iTrans Fixed Point Single/Dual Gas Monitor Introduction
(P/N: 77023554) INDUSTRIAL SCIENTIFIC 1-5
Conduit Connection: An EEx d certified sealing device, such as, a conduit
seal with setting compound, suitable for the conditions of use, and correctly
installed, shall be provided immediately to the entrance of the housing.
Unused openings: Unused openings shall be closed with suitable EEx d
certified closing elements.


iTrans Fixed Point Single/Dual Gas Monitor Hardware Overview
(P/N: 77023554) INDUSTRIAL SCIENTIFIC 2-1
HARDWARE OVERVIEW
Chapter
2
2.1. Main Electronics Unit (Housing)
The body is a cast aluminum housing that contains the electronics of the
gas monitor. Details of a single-gas housing are shown in Figure 2-1.
NOTE: Dimensions are in inches.
Figure 2-1. Details of a Single-Gas Gas Monitor

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2.2. Sensor
A list of supported sensors and their corresponding ranges and resolutions is given
in Table 2-1. Additional specifications are provided in Table 2-2.
Table 2-1. Sensor Types and Ranges
Sensor Gas Range/Resolution
Catalytic
Combustible
Gases (LEL) Infrared 0 -100% LEL in 1% increments
Hydrogen H20 - 999 ppm in 1 ppm increments
Oxygen O20 - 30.0% by vol. in 0.1% increments
Ammonia NH30 - 200 ppm in 1 ppm increments
(Div 2/Zone 2)
Carbon Monoxide CO 0 - 999 ppm in 1 ppm increments
Carbon
Monoxide/H2Null CO 0 - 999 ppm in 1 ppm increments
Hydrogen Sulfide H2S 0 - 500 ppm in 1 ppm increments
Sulfur Dioxide SO20.2 - 99.9 ppm in 0.1 ppm increments
Hydrogen
Cyanide HCN 0.2 – 30.0 ppm in 0.1 ppm increments
Hydrogen
Chloride HCl 0.2 - 30.0 ppm in 0.1 ppm increments
(Div 2/Zone 2)
Phosphine PH30 - 1.00 ppm in 0.01 ppm increments
Nitrogen Dioxide NO20.2 - 99.9 ppm in 0.1 ppm increments
Nitric Oxide NO 0 - 999 ppm in 1 ppm increments
Chlorine Cl20.2 - 99.9 ppm in 0.1 ppm increments
(Div 2/Zone 2)
Chlorine Dioxide ClO20.02 - 2.00 ppm in 0.01 ppm increments
(Div 2/Zone 2)
WARNING: When fitted with Zone 2 sensors, the main and remote
enclosures are only suitable for installation in Zone 2 locations.

iTrans Fixed Point Single/Dual Gas Monitor Hardware Overview
(P/N: 77023554) INDUSTRIAL SCIENTIFIC 2-3
Table 2-2. Sensor Specifications
Descriptions
Item Catalytic and Toxics Infrared
Aluminum, Anodized
Explosion-proof: Class I, Divisions 1
and 2 Groups B, C, D, and EEx d IIB
+H2 T5 (Europe), Ex d IICT4 or CT6
(China)
Sensor
Housing
Material Aluminum, Anodized w/Gore-Tex
Membrane (Division 2/Zone 2 toxics)
Suitable for Class I, Division 2 Groups
A, B, C, D, and EEx nA II T5 (Europe).
Stainless Steel
Explosion-proof: Class I,
Divisions 1 and 2 Groups B,
C, D, and EEx d IIB +H2 T4
(Europe), Ex d IICT4 or
CT6 (China)
Dimensions 3.0 3.0 inches (76 76 mm) 3.5 3.0 inches (89 76 mm)
Accuracy < 3% Toxic and Oxygen < 5% Combustibles
Protection
Class IP 66 or NEMA4X
2.3. Display
The gas monitor has a 4-digit, 7-segment LED display for each of 2
channels. A dual-gas sensor and sample display are shown in Figure 2-2.
Figure 2-2. The Display (Dual-Gas Monitor Shown)

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2.4. Inputs – Intrusive and Non-Intrusive
The gas monitor can be configured using intrusive and non-intrusive
means. Both methods of configuration are accomplished through physical inputs
that are visible behind the glass panel of the gas monitor.
A set of four keys are used when intrusive programming is appropriate (i.e., when
the enclosure can be removed and when the keys can be manually pressed). These
keys are the mode, increment (+), decrement (-), and enter keys. Refer to
Figure 2-3.
For applications that require non-intrusive manipulation, two magnetically-
activated reed switches are used to accomplish programming without removing the
cover. A magnetic wand is positioned over the appropriate reed switch (above the
glass face plate) without the wand physically touching the reed switches. The
locations of the reed switches are shown in Figure 2-3.
Figure 2-3. Locations of Input Keys and Reed Switches
Programming the gas monitor in both intrusive and non-intrusive modes
is explained in detail in Chapter 5: Operation.