TELEDYNE OLDHAM SIMTRONICS iTRANS 2 User manual

77036429-EN-Revision 7.0
iTRANS 2
FIXED POINT SINGLE OR DUAL GAS MONITOR
WITH DUAL ANALOG OUTPUTS
USER
MANUAL

iTRANS 2
FIXED POINT SINGLE OR DUAL GAS MONITOR
WITH DUAL ANALOG OUTPUTS
USER MANUAL
II
77036429-EN
Revision 7.0
User Manuals in other languages are available on
Website https://teledynegasandflamedetection.com
Copyright March 2021 by TELEDYNE OLDHAM SIMTRONICS S.A.S.
All rights reserved. No reproduction of all or part of this document, in any form, is permitted
without the written consent of TELEDYNE OLDHAM SIMTRONICS S.A.S.
is a trademark of TELEDYNE OLDHAM SIMTRONICS.
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.
All of the information that is provided in this document is accurate to the best of our knowledge.
As a result of continuous research and development, the specifications of this product may be
changed without prior notice.
TELEDYNE OLDHAM SIMTRONICS S.A.S.
Rue Orfila
Z.I. Est – CS 20417
62027 ARRAS Cedex

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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.
•The catalytic and IR sensors are factory configured to accurately monitor the gas for which
they are designated. It should be noted, however, that the LEL sensors WILL respond to
other combustible gases and are not gas-specific.
•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, TELEDYNE OLDHAM
SIMTRONICS 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.
•iTrans2 Stand-Alone versions with on-board visible alarm are to be installed in ordinary
locations only; however, remote sensors can be installed in hazardous locations (Gas
dependent. Read Agency Approvals paragraph).

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FOR IR SENSORS:
•The output of the IR sensors can be disrupted by sudden changes in temperature. If there
is an excessive change in the ambient temperatures, gas sample temperature or flow rate,
then the output signal will be momentarily frozen. Correct operation is restored when the
effects of the transient have settled. Rates of change in the ambient temperature should be
restricted to 2 °C/minute and gas flow rates kept below 0.6 L/minute.
•Extreme pressure variations will cause errors in readings. The unit should be recalibrated
if the atmospheric pressure change is greater than 10% from the original pressure.
•Do not expose the sensor to corrosive gases such as Hydrogen Sulphide.
•Do not allow condensation to occur inside the sensor.
•Infrared combustible sensors are not CSA approved.
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, TELEDYNE OLDHAM SIMTRONICS recommends prudent testing and/or
includes calibration after a gas alarm. All calibration service to sensors should be
recorded and accessible.
CAUTION:
For safety reasons, this equipment must be operated and serviced by
qualified personnel only.
Waste Electrical and Electronic Equipment (WEEE
directive)
European Union (and EEA) only. This symbol indicates that, in conformity with directive
DEEE (2002/96/CE) and according to local regulations, this product may not be
discarded together with household waste.
It must be disposed of in a collection area that is set aside for this purpose, for example at a site
that is officially designated for the recycling of electrical and electronic equipment (EEE) or a
point of exchange for authorized products in the event of the acquisition of a new product of the
same type as before.

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Table of Contents
1Overview........................................................................................... 1
1.1 Overview of the Gas Monitor.......................................................1
1.2 Specifications......................................................................................................1
1.3 Agency Approvals ............................................................................................3
2Hardware Overview ....................................................................... 5
2.1 Main Electronics Unit (Housing)....................................................................5
2.2 Sensor .....................................................................................................................6
2.3 Display....................................................................................................................6
2.4 Inputs – Intrusive and Non-Intrusive ............................................................6
2.5 Electronics Modules..........................................................................................7
3Installation ........................................................................................ 9
3.1 Introduction .........................................................................................................9
3.2 Installation Considerations.............................................................................9
3.3 Wall Mounting.....................................................................................................9
3.4 Column Mounting .............................................................................................9
4System Wiring................................................................................... 11
4.1 Introduction .........................................................................................................11
4.2 Wiring Preparation ............................................................................................11
4.3 Alarm Relay Wiring (J1, J5, and J6) ............................................................12
4.4 Power and Output Wiring (J1)......................................................................13
4.5 Sensor Wiring (J3)...............................................................................................13
4.6 Digital ModBus RTU Interface Wiring (J1) .................................................17
4.7 Wiring Conclusion..............................................................................................19
5Operation.......................................................................................... 21
5.1 Initial Start-up.......................................................................................................21
5.2 Warm-up Period.................................................................................................21
5.3 Normal Operating Mode................................................................................21
5.4 Programming Mode Overview ....................................................................22
5.5 Programming Mode – Non-intrusive Operation ....................................23
5.6 Programming Mode – Push Button Operation.......................................27
6Modbus Interface ........................................................................... 35

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6.1 Introduction .........................................................................................................35
6.2 Sample Gas Reading via ModBus Network............................................36
6.3 ModBus Register List..........................................................................................36
6.4 ModBus Resources ............................................................................................39
6.5 Termination ..........................................................................................................39
7Maintenance ................................................................................... 41
7.1 Introduction .........................................................................................................41
7.2 Sensor Replacement........................................................................................42
7.3 Zero and Calibration........................................................................................42
8Troubleshooting............................................................................... 43
8.1 Introduction .........................................................................................................43
8.2 Diagnosing Common Problems...................................................................43
8.3Fault Codes..........................................................................................................44
8.4 Function Codes..................................................................................................44
9Warranty............................................................................................ 45
9.1 Warranty................................................................................................................45
9.2 Limitation of Liability .........................................................................................45
Appendix A HART Interface .............................................................. 47
A.1 Introduction .........................................................................................................47
A.2 Hardware Overview .........................................................................................48
A.3 Installation ............................................................................................................49
A.4 System Wiring ......................................................................................................49
A.5 Operation .............................................................................................................52
A.6 HART Interface....................................................................................................54
A.7 User Commands.................................................................................................56
Appendix B Acronyms and Abbreviations................................... 61
Appendix C Decimal, Binary, And Hex Equivalents................... 63
Appendix D Ordering Matrix ............................................................ 67
Appendix E Factory Default Settings.............................................. 69
Appendix F LEL Correlation Factors ............................................... 70
Appendix G Declarations of EU conformity .................................. 72

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1Overview
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 ho
rns, or warning
lights. Two of the relays can be programmed for alarm
activation, while the third relay is a fault protection relay.
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.
Figure 1-1 Typical Gas
Monitor with Single Gas Sensor
(Stainless Steel Option)
1.2 Specifications
Specifications for the gas monitor are listed in Table 1-1.
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 x 153 x 129 mm)
Sensors
Combustible Gases: Catalytic bead and/or Non-Dispersive Infrared (NDIR)
Oxygen/Toxic Gases: Electrochemical diffusion

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Item
Description
Input Voltage 12-28 VDC operating range (24 VDC typical)
Input Current
(Max)
Toxic
Gas/Oxygen
150 mA@24 VDC (single gas)
200 mA@24 VDC (single gas + HART)
Combustible
Gases (Catalytic)
250 mA@24 VDC, 0.8 A peak (single gas)
300 mA@24 VDC, 0.8 A peak (single gas + HART)
Combustible
Gases (Infrared)
170 mA@24 VDC, 0.5 A peak (single gas)
220 mA@24 VDC, 0.5 A peak (single gas + HART)
Combined
Catalytic/Infrared
350 mA@24 VDC, 1.2 A peak (two gas)
400 mA@24 VDC, 1.2 A peak (two gas + HART)
Display
Dual-channel split-screen LED display (4-digit, 7-segment arrangement per
channel) provides simultaneous display of one or two gases.
Signal Outputs 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.
Analog 4-20 mA (linear analog)
Alarm Relays
Quantity 3 alarm relays: Two user-programmable relays,
SPST, N.O.; plus one fault relay, SPST, N.C.
Contact Capacity 5A @ 30 VDC
5A @ 30 VAC
Temperature
Range -40 ºC ~ +75 ºC (-40 ºF ~ +167 ºF)
Humidity Range
10% - 90% RH (non-condensing), typical
Pressure Atmospheric pressure ±10%
Weight 2.9 Kg (6.4 lbs.)
Table 1-1 Specifications for the Monitor

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Sensor
Gas
Range/Resolution
Combustible Gases LEL 0 -100% LELin 1%increments
Hydrogen H20 - 999 ppm in 1 ppmincrements
Oxygen O20 - 30.0% by volin 0.1%increments
Ammonia
NH
3
0 - 500 ppmin 1 ppmincrements
Carbon Monoxide CO 0 - 999 ppmin 1 ppmincrements
Carbon Monoxide/H2 Null CO 0 - 999 ppmin 1 ppmincrements
Hydrogen Sulfide
H
2
S
0 - 500 ppmin 1 ppmincrements
Sulfur Dioxide SO20.2 - 99.9 ppm in 0.1 ppmincrements
Hydrogen Cyanide
HCN
0.2 – 30.0 ppm in 0.1 ppmincrements
Hydrogen Chloride HCl 0.2 - 30.0 ppm in 0.1 ppmincrements
Phosphine PH30 - 1.00 ppm in 0.01 ppmincrements
Nitrogen Dioxide
NO
2
0.2 - 99.9 ppm in 0.1 ppmincrements
Nitric Oxide NO 0 - 999 ppm in 1 ppmincrements
Chlorine Cl20.2 - 99.9 ppm in 0.1 ppmincrements
Chlorine Dioxide
ClO
2
0.02 - 1.00 ppmin 0.01 ppm increments
Carbon Dioxide (IR) CO20 – 0.50% Volin 0.01%increments
Carbon Dioxide (IR) CO20 – 5.00% Volin 0.01%increments
Carbon Dioxide (IR) CO20 – 100% Volin 1% Volincrements
Table 1-2 Sensor Ranges
1.3 Agency Approvals
The without infrared combustible sensors 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
•Electrical 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 (iTrans
2 with catalytic sensors only)

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•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 (iTrans 2 with
catalytic sensors only)
•CSA Std C22.2 No. 213-M1987-Non-incendive Electrical Equipment for Use in Class I,
Division 2 Hazardous Locations
Marking: Transmitter Class I, Div 1, Groups B, C, D – AEx d IIB + H2 T5
Sensor
(gas dependent)
(1)Class I, Div 1, Groups B, C, D – AEx d IIB + H2 T5
(2)Class I, Div 2, Groups A, B, C, D – AEx d IIB + H2 T5
The is certified under the IECEx scheme to:
•IECEx 60079-0:2011 (Ed. 6.0) – Explosive Atmospheres – Part 0: General requirements
•IECEx 60079-1: 2014 (Ed. 7.0) – Explosive Atmospheres – Part 1: Equipment protection
by flameproof enclosures ‘d’
•IECEx 60079-15:2010 (Ed. 4) – Explosive Atmospheres – Part 15: Equipment protection
by type of protection ‘n’
Marking: Transmitter Ex db IIB+H2 T5; IP66
Sensor (gas dependent) (1)Ex db IIB+H2 T5 ; IP66
(2)Ex nA IIC T5 Gc ; IP66
(1)LEL, H2, O2, CO, H2S, SO2, HCN, PH3, NO2, NO, CO2
(2)Cl2, HCl, NH3, ClO2

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2Hardware Overview
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.
Figure 2-1 Details of a Single-Gas Gas Monitor

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2.2 Sensor
Item
Descriptions
Sensor Housing
Material
Aluminum, Anodized, Explosion-proof: Class I, Divisions 1 and 2,
Groups B, C, D and Ex d IICT6 Gb (China) and Ex d IIB + H2T5 (IECEx)
Aluminum, Anodized w/Gore-Tex Membrane: Class I, Division 2,
Groups A, B, C, D and Ex nA IIC T5 (IECEx)
Dimensions 3.0 × 3.0 inches (76 × 76 mm)
Accuracy
< ± 3% Toxic and Oxygen
For Combustibles:
For test gas concentrations up to and including 50% of full scale, the
deviation shall not exceed ±3% of full scale gas concentration.
For test gas concentrations above 50% of full scale, the deviation shall
not exceed ±5% of full scale gas concentration.
Protection Class IP 66 or NEMA 4X
Table 2-1 Sensor Specifications
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)
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

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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.
2.5 Electronics Modules
The electronics module of the gas monitor contains connectors and jumpers for wiring
and configuring the device. The electronics module for a main unit is shown in Figure 2-4.
The electronics module for a remote unit is shown in
Figure 2-5. Wiring details are explained in 4 System Wiring.

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Figure 2-4 Electronics Module for (Main Unit)
Figure 2-5 Electronics Board for Remote Sensor

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3Installation
3.1 Introduction
The can be mounted in one of two ways. The unit can be wall-mounted using the wall
mounting holes in the enclosure, or it can be mounted onto a column using U-bolts. Each of these
options is discussed in this chapter. Be sure to review the installation considerations before
mounting the gas monitor.
3.2 Installation Considerations
Regardless of the installation type (wall mounting or column mounting), the should be
installed at or near the location of a possible leak or the source of emissions. Installation height
depends on the density of the gas being monitored. Moreover, speed and direction of air flow,
and relative position to potential leaking points should also be considered.
IMPORTANT: The gas monitor must not be installed on vibrating or heat generating
sources.
3.3 Wall Mounting
If your application is best addressed using a wall-mounted gas monitor, then use the four 8 mm
mounting holes in the enclosure to secure the to an appropriate location on the wall. Refer
to Figure 3-1.
3.4 Column Mounting
If your application is best addressed using a column-mounted gas monitor, then use the four 8
mm mounting holes and two U-bolts to secure the to an appropriately located segment
of a target pipe or conduit. Refer to Figure 3-2.

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Figure 3-1 Mounting the Gas Monitor on a Wall
Figure 3-2 Mounting the Gas Monitor on a Column Using U-Bolts

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4System Wiring
4.1 Introduction
This chapter outlines the steps required for wiring the gas monitor. These steps include the
following:
•Wiring Preparation
•Sensor Wiring
•Alarm Relay Wiring
•Power and Output Wiring
•ModBus Interface Wiring
Each of these steps is outlined in the sections that follow.
IMPORTANT: Perform all wiring in accordance with local electrical codes and local authorities
having jurisdiction.
IMPORTANT: DC signal and AC power should not be run in the same conduit.
NOTE: All field wiring colors are arbitrary (unless provided by TELEDYNE OLDHAM
SIMTRONICS).
4.2 Wiring Preparation
1. Collect the appropriate types and lengths of wire.
•For control wire, use #18 AWG (0.9 mm²) insulated, shielded cable.
•For analog signal and power wire, use three-conductor (or four-conductor for dual
channel) #18 AWG (0.9 mm²) insulated and shielded cable.
•For digital ModBus signal and power, use a minimum of five-conductor #18 AWG (0.9
mm²) insulated and shielded cable.
2. Power down the unit.
3. Unthread the windowed top from the housing.
4. Gently pull out the electronics module and place it safely to the side of the unit.
5. Thread control, signal, and power wires into the transmitter housing.
6. Shielding from either the controller or remote sensors should be bonded to the enclosure
screw located inside the .

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IMPORTANT: Use of this product in areas where it may be subject to large amounts of
electromagnetic interference may affect the reliable operation of this device and should be
avoided.
WARNING: Supply wire with a minimum rating of 90°C must be used for interconnection to the
.
NOTE: For classified locations, a “poured” wire seal must be installed within 18 inches (457mm)
of the main unit for both power entry and remote sensors.
NOTE: Remove power from the before making any wiring connections.
4.3 Alarm Relay Wiring (J1, J5, and J6)
To connect the control wires to the three relay terminals on the relay board, wire the unit
to the connectors shown in Figure 2-4. The low alarm relay is activated when the low alarm
threshold is met. This is a non-latching, Normally Open (NO) contact. The high alarm relay is
activated when the high alarm threshold is met. This is a non-latching, Normally Open (NO)
contact. The fault alarm relay is activated upon power-up of the . When the fault condition
is met, the circuit opens. This is an Electronically closed (NC) contact. See Figure 4-1 for relay
wiring.
NOTE: It is recommended that on-board relays should not be used to drive loads directly. On-
board relays should be used to drive a secondary, higher-power relay which is connected to the
control device (e.g., strobe, siren, exhaust fan, etc.).
Figure 4-1 Alarm Relay Connectors J6, J5 and J1

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4.4 Power and Output Wiring (J1)
Connect the power and signal wires to the appropriate wiring terminals as follows.
•24 V:Connect 24 VDC (12-28 VDC) supply power
•CH 1:Channel 1, 4-20 mA output signal
•CH 2:Channel 2, 4-20 mA output signal
•GND:DC return
Figure 4-2 Power and Signal Connector J1 on the
NOTE: Use supplied green conductor for enclosure ground. Public 485 GND is to be used for
ModBus digital ground.
NOTE: The is a 3- or 4-wire 4-20 mA device. For dual sensor configuration you must
have a second 4-20 mA signal wire pulled to the unit.
NOTE: When not using 4-20 mA outputs, use the supplied resistors to connect CH-1 and CH-2
to GND. If these resistors are not connected and the 4-20 mA outputs are not used, a “P” will
appear on the display, indicating an open loop condition.
4.5 Sensor Wiring (J3)
Connect the sensor wires (for on-board, remote or stand-alone) to the appropriate wiring
terminals as follows.
•24 V:Red wire from sensor head
•485A:Yellow wire from sensor head
•485B:Black wire from sensor head
•GND:Green wire from sensor head
NOTE: Shielding from either the controller or remote sensors should be bonded to the enclosure
screw located inside the .
NOTE: The 24 V terminal supplies 24 VDC to the sensor for power. This terminal should not be
connected to the output of a 24 VDC power supply.

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Figure 4-3 Sensor Connector J3 on the
NOTE: For dual-sensor configurations, place both of the same colored wires in the appropriate
terminal block and firmly tighten.
NOTE: Use #18 AWG (0.9 mm²) shielded cable for remote sensors. Maximum distance is 200
meters.
NOTE: When wiring remote sensors to the , “485 B” on J3 should be connected to “B-”
in the remote sensor enclosure, and “485 A” on J3 should be connected to “A+” in the remote
sensor enclosure.
NOTE: For remote or standalone sensors, there are four terminal blocks located in the remote
sensor housing. These terminal blocks are all tied together and follow the same wiring scheme
mentioned above.
Figure 4-4 Wiring Diagram for a Single On-board Sensor