SSS-903 TG-E
Install Guide
Addition; Appendix II
Warranty & Return Policy
Information and technical data disclosed in this document
may be used and distributed only for the purposes and to
the extent specifically authorized by ESP Safety Inc.
ESP Safety Inc. Reserves the right to change published
specifications and designs without prior notice
OPERATING MANUAL
SSS-903 Toxic Gas Detection System
Model SSS-903 Transmitter and Controller
Model PGU-IR Infrared Optical Gas Sensor
Model PGU-P Photo Ionization Gas Sensor
Model PGU-E Electrochemical Gas Sensor
Model PGU-C Catalytic Bead Gas Sensor
SSS-903 TG-E
Install Guide
General Information .............................................................................................................. 3
Specifications of SSS-903 with PGU Sensors ........................................................................ 4
SSS-903 Theory of Operation .............................................................................................. 11
Data Communication ........................................................................................................... 17
IMPORTANT SAFETY INFORMATION................................................................................... 18
Physical Installation Procedure .......................................................................................... 19
Physical Installation Quick Guide........................................................................................ 20
Wiring Requirements .......................................................................................................... 24
Power up and Stand Alone Operation of the SSS-903 ........................................................ 31
RS-485 Modbus Digital Communication and Operation ...................................................... 32
Calibration Procedures ........................................................................................................ 33
Non-Invasive Calibration Magnet Procedure ...................................................................... 33
Non-Invasive Calibration Procedure with HART Communicator……………………………..….33
Bench Test Calibration Procedure with ESP Commander ................................................. 438
Unpacking A New SSS-903 .................................................................................................. 44
Appendix 1 Explosion Proof Design……………………………………………… .............. …………45
Appendix 2 Warranty & Return Policy .............. ……………………………………………………46
SSS-903 TG-E
Install Guide
This instruction guide details the specification, application and operation of the ESP Safety Inc. SSS-903 with an included
sensor. The SSS-903 System consists of two components, a receiver and gas specific sensor that have been factory
configured and calibrated to provide detection of toxic, flammable and combustible gases in open or closed environments. The product
includes multiple features required to report alarms when the toxic gas concentrations in the environment
reach three independently programmed levels. Each alarm also triggers a relay that is provided as a standard feature,
which can be used to operate warning devices, sirens, valves or switches.
The SSS-903 receiver is a versatile product that can be used in a specific proximity or in a decoupled mode with the sensor
and receiver head located up to 500 feet apart. Furthermore, any SSS-903 can be reconfigured in the field to detect toxic
gases using optional sensor replacements.
The SSS-903 system is recommended for applications that require a gas detector with localized digital readout of detected
gas levels. It comes factory standard for with Analog 4-20mA output with embedded HART, an independent HART connector
that is conveniently located on the SSS-903 enclosure able, relay contacts, and Modbus RS485. The system is comprised of an
SSS-903 Receiver and plug-in universal PGU sensors for electrochemical (PGU-E) , infrared (PGU-IR) ,photo-ionized (PGU-P) and
catalytic bead (PGU-C)detection. Power is supplied from an external 24 VDC nominal power source (source can range 18-3VDC). In
operation the
SSS-903 system has been designed for operation in temperature ranges from minus 40 to 75 °С (without internal heated option
activation) and minus 60 to 75 °С (with activated internal heated option) and relative humidity of up to 100 % (non-condensing)
The SSS-903 receiver includes 5 LED annunciators plus an easily readable LCD display. On the display an operator can determine
information of alarm status, gas detected, current level detected and view a Time Weighted Average (TWA) run time graphic
showing each event and level detected during a user programmed time from 3 to 30 minutes. The design of the SSS-903 is an
approved product for use in control monitoring of gas contamination levels with flammable and toxic gases present in the
working area environment of oil, gas and chemical industries All electronics are enclosed in explosion-proof aluminum or
stainless steel housings that have been certified by FM-Approvals for use in explosive areas pertinent to classes 1 and 2 with the
potential hazard of forming explosive gas mixtures attributed to the subgroup IIС and to explosion hazard categories Т1–Т6,
inclusive of the following zones, premises and facilities:
Drilling and production platforms
Refineries
Bulk terminals and tank farms
Compressor stations
Pipelines
Transportation facilities
Petrochemical facilities
Paint Manufacturing
Fertilizer plants
Fuel loading facilities
Residential areas
Boiler stations
Non-invasive calibrations can be performed in the field using an included magnetic wand or a HART communicator.
A device descriptor file is available from ESP Safety for use with a HART communicator. Calibration can also be performed with an
included Windows PC application, ESP Commander. Both HART and ESP Commander applications can supply real time output of
current operational data plus access a non-volatile memory in the SSS-903 for further diagnostic analysis.
General Information
Applications
SSS-903 TG-E
Install Guide
Electrical Characteristics
Operational Characteristics
Mechanical Characteristics
+24VDC Nominal (+18 to 32VDC)
2 W-standby
5 W-during alarms
+4-20mA industry standard analog with embedded HART
Digital RS-485 Modbus RTU
HART interface with easy access dedicated connector
4 “Dry Contact” relays (NO/Form-A)
All Relays Contact Rating 1Amp@125VAC/30VDC
3 User Programmed Alarm Relays
1 Fault Condition Relay
GT Sensor Interface to SSS903 Receiver
Digital RS-485 Modbus RTU
*Note All ESP Safety gas detector products can be interfaced with the SSS-903
Electrochemical: PGU-E
Infrared: PGU-IR
Photo Ionized: PGU-P
Up to 100%, non-condensing
(Withstands up to 100% RH for short periods)
Standard Operation: -40oF to +167oF (-40oC to +75oC)
With Optic Heater Enabled: –76oF to +167oF (-60oC to +75oC)
EN50081-1 / Class B E> 50270
*Operates with no interference from a 5 watt walkie talkie keyed (transmitting) at 1 meter
Tri-color status LED indicates operational mode, fault, and gas presence.
Three LED indicators for Alarms activation
A fourth LED indicates the unit is in calibration mode
Displayed Information
(Illuminated LCD Display)
Continuous sensor data
Gas Type
Measuring Units
Three Fixed Alarm Thresholds
Graphic display of trending data for Peak Readings and Time-Weighted Average (TWA) of gas
concentration 3-30 minutes
Explosion Proof Labels for SSS903 & PGU Sensors
Ex d [ia Ga] IIC T6 Gb
Ex d ia IIC T6
Dimensions of SSS-903
Receiver
Dimensions of PGU Sensors
Stainless Steel Grade-316
Specifications of SSS-903 with PGU Sensors
SSS-903 TG-E
Install Guide
Dimensions Diagram of SSS-903 Receiver
All dimensions are in mm
SSS-903 TG-E
Install Guide
Table 1: SSS-903 with PGU-E Electrochemical Gas Sensor Range, Accuracy and
Response Times
Using Gas Specific Electrochemical Detectors
*Response Time is the time to reach a percentage of final reading when gas concentration is equal to full scale of the sensor
range of detection. (i.e. T50=50% 0f Range)
**Some sensors have multiple ranges one of which is determined by the user during setup or calibration
T50 < 40 seconds
Т90 < 60 seconds
T20 < 10 seconds
Т90 < 25 seconds
(0 - 500) ppm
T50 < 30 seconds
Т90 < 90 seconds
T20 < 10 seconds
T50 < 12 seconds
Т90 < 25 seconds
T50 < 12 seconds
Т90 < 25 seconds
T50 < 12 seconds
Т90 < 25 seconds
T50 < 30 seconds
Т90 < 90 seconds
SSS-903 TG-E
Install Guide
Using Gas Specific Photoionized Detectors
*Response Time is the time to reach a percentage of final reading when gas concentration is equal to full scale of the sensor
range of detection. (i.e. T50=50% 0f Range)
**Some sensors have multiple ranges one of which is determined by the user during setup or calibration
Note: All gases with ionization potential <10.6 eV
Т50 < 9 seconds
Т90 <25 seconds
(0 - 100) ppm
Other ranges per
request
Table 2: SSS-903 with PGU-P Photo Ionization Gas Sensor:
Range, Accuracy and Response Times
SSS-903 TG-E
Install Guide
Using Gas Specific IR Detectors
*Response Time is the time to reach a percentage of final reading when gas concentration is equal to full scale of the sensor
range of detection. (i.e. T50=50% 0f Range)
± 3% to 50% LEL
± 5% from 51%
T20 < 5 seconds
Т90 < 25 seconds
(0 to 2) % Vol
(0 to 5 ) % vol
( 1 – 3000) ppm
Table 3: SSS-903 with PGU-IR Infrared Optical Detection:
Range Accuracy and Response Times
SSS-903 TG-E
Install Guide
Using Catalytic Bead (pellisor) sensor specifically for detection of hydrogen
*Response Time is the time to reach a percentage of final reading when gas concentration is equal to full scale of the sensor
range of detection. (i.e. T50=50% 0f Range)
** All data refers to catalytic bead sensor as tested with H2 gas from an approved source. The sensor data listed is based on ideal test
environment with no interference from other gases
< ± 10% of
measured value
Table 4: SSS-903 with PGU-C Catalytic Bead Sensor:
Range Accuracy and Response Times
SSS-903 TG-E
Install Guide
CE 0539 II 2 G
Ex d[ia] IIC T4 (Tamb 75°C)
IP 66
Ex d [ia] IIC T4
(Tamb 75°C)
IP 66
1 Ex d [ia] IIC T4 X T= -60°C....75°C
EN 60079-0: 2006
EN 60079-1: 2007
EN 61779-1: 2000
EN 60529: 1991+A1: 2000
EN 50270: 2006.
Certifications
SSS-903 TG-E
Install Guide
The SSS-903 is physically designed to perform in a wide range of hazardous environments and harsh weather conditions.
Employing a durable enclosure that can withstand these conditions and even explosion is key to the operation and function
of the device.
The SSS-903 is an elegant design that uses only two printed circuit board assemblies (PCBA) that have also been designed to
resist the effects of environmental challenges. The PCBAs are installed in a layered fashion with a single interconnection for easy
removal.
The Controller PCBA provides all information to the user via LED and LCD display. A micro controller with embedded software
performs all functions used in communication and control. As noted the controller card also functions as the driver for the
LCD display and performs all calculations used for the timed graphic HART. Event information displayed on the graphic cHART
is also stored in a Non-Volatile memory within the PGU sensor that can be accessed using ModBus or a HART communicator.
The second module is the Power PCBA. This PCBA accepts and regulates the externally supplied power source in addition to
all signal connections. Four solid state-sealed relays are also located on the Power PCBA eliminating the potential of electronic
discharge associated with mechanical relays.
All signals enter and exit the enclosure via ¾” threaded female attachments for conduit as required by the user application
and local regulations.
¾ Inch Inlet/Outlet Receptacles
For Explosion Proof Conduit and
Cabling
Dedicated HART Device
Communication Connector
with Protective Cover
Installed
.35” Diameter Surface
Mount (Left and Right)
Screw On Explosion Prove Housing Cover with
Shatter Proof Glass Window
Physical Earth
Ground Clamp
Splash Guard and Gas Collector
Removable Detector Module Housing
cover with Lock Screw
SSS-903 Receiver Operation
Figure 1 SSS-903 Receiver with PGU Sensor Installed
SSS-903 TG-E
Install Guide
Figure 2- SSS-903 LED
Indicators
Figure 3 -
SSS-903 LCD Display
Detected Gas
Current Value
Time Value of
Graphic Display
Operational Status
Green – Normal Operation
Yellow – Alarm Active
Red – Fault Condition
SSS-903 TG-E
Install Guide
The PGU-P performs selective detection of hydrocarbon molecules using infrared light and
photo ionization detectors (PID). Air containing molecules of the selected combustible gas
passes into a collection chamber that has an IR source and detector. The molecules containing
the combustible gas absorb the IR photons and become ionized. Ionized molecules create an
electric current that is measured by the detector. The electric current increases as the amount
of gas molecules in the chamber increases. The current is measured and processed by the
PGU-P sensor, generating the signals that are passed to the SSS-903 receiver via RS-485. Each
detector is factor programmed for the gas requested by the customer at the time of purchase.
Operation the PGU-IR is based on selective signal disruption by hydrocarbon molecules when an
infrared light source is projected to an optical detector. Measurement for a specific gas is
determined by passing the IR energy through a filter placed between the source and a chamber
where the gas is collected. If nogas is present, the detector will receive all of the energy
radiated by the IR source and generating an electrical current. When gas molecules enter the
collection chamber, each molecule of the gas blocks the IR energy reducing the output of the
detector, which is then processed by the PGU-IR sensor. Each detector is delivered preset for a
specific gas, in the example shown, the gas is Methane (CH4), which ionizes at two points on the
light spectrum, one for each Atomic Element, and are measured as wave numbers (cm-1).
PGU-P Photo Ionization Gas Sensor Theory of Operation
Figure-4 PGU-P Detector
PGU-IR Infrared Optical Gas SensorTheory of
Operation
SSS-903 TG-E
Install Guide
The PGU-P sensor contains electrode in contact with an electrolyte. The target gas
diffuses into the sensor through a membrane and comes into contact with electrodes
where it is oxidized. The electrochemical reaction results in an electric current that passes
to PGE-P microcontroller and from there to the SSS-903 receiver. The magnitude of the
current is controlled by how much of the target gas is oxidized by the electrode. Output
current from the sensor is also linearly proportional to the gas concentration. A linear
output allows for more precise measurement of low concentrations and much simpler
calibration.
PGU-E Electrochemical Gas Sensor Theory of Operation
SSS-903 TG-E
Install Guide
The PGU-C catalytic bead sensor oxidizes the target gas on the surface of a heated
alumina bead. The resulting heat of combustion results in a change in resistivity of the
element that is directly proportional to the concentration of the gas. A precious metal
catalyst is embedded onto the surface of the alumina bead to lower the oxidation
temperature. Two platinum wire leads are embedded in the alumina bead and connected
electrically in a Wheatstone bridge circuit. Heat is generated by passing current through
the leads.
PGU-C Catalytic Bead Gas Sensor Theory of Operation
SSS-903 TG-E
Install Guide
Field Replaceable Detector
Module
Housing Label Must
Match with Detector
Gas.
Removable Housing
Cover with Filter
Each PGU sensor consists of PGU module with imbedded processing and a single gas specific plug-in
electrochemical, infrared (optical) or photo-ionized detector. There is a filter located between the
collection chamber and the detector to minimize potential contamination from dust or moisture. The
collection chamber is covered by a splashguard, which also serves as the gas collector. The
splashguard also has an inlet nipple for calibration purposes.
Each PGU detector internally stores the data reported to the SSS-903, HART, or Modbus. All
calibration information is also stored in the PGU module processor, thus any PGU module can be
moved to another SSS-903 receiver and resume data collection from the time of removal.
The detector module may be replaced in the field with a one that is intended for use to detect the
same gas. If a different gas is required a replacement PGU module must be ordered from ESP Safety
or their representative. Aside from detector or filter replacement there are no user serviceable parts
in the PGU sensor.
Figure 7 – PGU Detector Module