General Monitors S4000CH User manual

The information and technical data disclosed in
this document may be used and disseminated
only for the purposes and to the extent
specifically authorized in writing by General
Monitors.
Instruction Manual 10-16
General Monitors reserves the right to change
published specifications and designs without
prior notice.
MANS4000CH
Part No. MANS4000CH
Revision N/10-16
Model S4000CH
Intelligent Sensor for
Combustible Gas Detection

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Model S4000CH
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Table of Contents
TABLE OF FIGURES..................................................................................................................VI
TABLE OF TABLES...................................................................................................................VII
QUICK START GUIDE.................................................................................................................1
Mounting and Wiring ...............................................................................................................................1
Tools Required …………………………………………………………………………………………………..1
Terminal Connections .............................................................................................................................3
1.0 INTRODUCTION ....................................................................................................................5
1.1 Protection for Life.......................................................................................................................5
1.2 Special Warnings .......................................................................................................................5
1.3 System Integrity Verification ......................................................................................................6
2.0 PRODUCT DESCRIPTION.....................................................................................................8
2.1 General Description ...................................................................................................................8
3.0 INSTALLATION....................................................................................................................10
3.1 Receipt of Equipment...............................................................................................................10
3.2 Tools Required.........................................................................................................................10
3.3 Choosing Product Locations ....................................................................................................10
3.3.1 Remote Mounting of the Sensor from the Electronics ................................................11
3.4 Mounting and Wiring ................................................................................................................12
3.5 Terminal Connections ..............................................................................................................13
3.5.1 Terminal Block TB1 – Sensor Connections ................................................................15
3.5.2 Terminal Block TB2 – Power and Signal Connections ...............................................15
3.5.3 DC Power and COM Connections ..............................................................................17
3.5.4 Analog Signal Connections.........................................................................................17
3.5.5 ARGC Terminal Connections......................................................................................18
3.5.6 Terminal Block TB3 – Relay Connections ..................................................................18
3.5.7 European Union (EU) Approved Applications.............................................................19
3.5.8 Cable Termination in the Non-Hazardous Area..........................................................19
3.6 Maintaining the X/P Integrity ....................................................................................................20
3.7 Start-Up Checklist ....................................................................................................................21
3.8 Start-Up....................................................................................................................................21
3.9 Relay Reset..............................................................................................................................21
3.10 User Selectable Options ..........................................................................................................22
3.11 Available Separate Purchase Options .....................................................................................22
3.11.1 Model S4000CH User Menu Structure .......................................................................23
3.11.2 Calibration Level .........................................................................................................24
3.11.3 Warning Relay Settings ..............................................................................................24
3.11.4 Alarm Relay Settings...................................................................................................24
3.11.5 Modbus Channel 1 Settings........................................................................................25
3.11.6 Modbus Channel 2 Settings........................................................................................25
3.12 HART/Modbus SELECT...........................................................................................................26
3.13 Gas Check Mode .....................................................................................................................26
3.13.1 Calibration Check........................................................................................................26
3.14 Calibration ................................................................................................................................27

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3.14.1 Calibration Procedure .................................................................................................27
3.14.2 Aborting Calibration.....................................................................................................28
3.14.3 Adjustable Calibration Level .......................................................................................29
3.14.4 Remaining Sensor Life................................................................................................29
3.14.5 Initializing the Remaining Sensor Life.........................................................................29
3.15 Calibration Equipment..............................................................................................................29
3.15.1 Portable Purge Calibrator ...........................................................................................29
3.16 Remote Gas Calibrator ............................................................................................................30
3.17 ARGC Gas Control...................................................................................................................30
3.18 Automatic Remote Gas Calibrator (ARGC) .............................................................................31
3.19 Calibration Using the ARGC ....................................................................................................31
4.0 MAINTENANCE ...................................................................................................................33
4.1 General Maintenance...............................................................................................................33
4.2 Storage.....................................................................................................................................33
5.0 TROUBLESHOOTING .........................................................................................................34
5.1 Fault Codes & Their Remedies................................................................................................34
5.1.1 F2 Failed to Complete Calibration ..............................................................................34
5.1.2 F3 Flash Checksum Error ...........................................................................................34
5.1.3 F4 Sensor Error...........................................................................................................34
5.1.4 F5 Unused...................................................................................................................35
5.1.5 F6 Low Supply Voltage ...............................................................................................35
5.1.6 F7 EEPROM Error ......................................................................................................35
5.1.7 F8 Failure to Complete Setup .....................................................................................35
5.1.8 F9 Gas Check Period Exceeded.................................................................................35
5.1.9 F10 Switch Error .........................................................................................................35
5.1.10 F11 Internal Error........................................................................................................36
5.1.11 F12 ARGC fault...........................................................................................................36
5.2 General Monitors’ Offices.........................................................................................................36
6.0 MODBUS INTERFACE ........................................................................................................37
6.1 Baud Rate ................................................................................................................................37
6.2 Data Format .............................................................................................................................37
6.3 Modbus Read Status Protocol (Query/Response)...................................................................37
6.3.1 Modbus Read Query Message ...................................................................................37
6.3.2 Modbus Read Response Message.............................................................................37
6.4 Modbus Write Command Protocol (Query/Response) ............................................................38
6.4.1 Modbus Write Query Message ...................................................................................38
6.4.2 Modbus Write Response Message.............................................................................38
6.5 Function Codes Supported ......................................................................................................38
6.6 Exception Responses and Exception Codes...........................................................................38
6.6.1 Exception Response ...................................................................................................38
6.6.2 Exception Code...........................................................................................................39
6.7 S4000CH Command Register Locations.................................................................................40
6.8 S4000CH Command Register Details .....................................................................................42
6.8.1 Analog (00h)................................................................................................................42
6.8.2 Mode (01h)..................................................................................................................42
6.8.3 Status/Error (03h)........................................................................................................43
6.8.4 Unit Type (04h) ...........................................................................................................43
6.8.5 Software Revision (05h)..............................................................................................43
6.8.6 Status Block (06h).......................................................................................................43

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6.8.7 Analog Value (06h) .....................................................................................................43
6.8.8 Mode & Error (07h) .....................................................................................................44
6.8.9 Error & Sensor Life (08h) ............................................................................................44
6.8.10 Display (0x09h & 0x0Ah) ............................................................................................44
6.8.11 Serial Number (0Bh/0Ch)............................................................................................45
6.8.12 Alarm Settings (0Dh)...................................................................................................45
6.8.13 Warn Settings (0Eh)....................................................................................................45
6.8.14 Com1 Address (0Fh)...................................................................................................46
6.8.15 Com1 Baud Rate (10h) ...............................................................................................46
6.8.16 Com1 Data Format (11h) ............................................................................................46
6.8.17 Com2 Address (12h)...................................................................................................47
6.8.18 Com2 Baud Rate (13h) ...............................................................................................47
6.8.19 Com2 Data Format (14h) ............................................................................................48
6.8.20 Calibration Level (15h)................................................................................................48
6.8.21 Reset Alarms (16h) .....................................................................................................48
6.8.22 Sensor Life (17h).........................................................................................................48
6.8.23 HazardWatch (Co – Calibration Output) (19h)............................................................49
6.8.24 ARGC (1Ah)................................................................................................................49
6.8.25 PLC Remote Gas Calibration......................................................................................49
6.8.26 HART Enable (1Dh) ....................................................................................................49
6.8.27 HART Test (1Eh).........................................................................................................49
6.8.28 Abort Calibration (1Fh)................................................................................................50
6.8.29 Total Receive Errors (20h)..........................................................................................50
6.8.30 Bus Activity Rate % (21h) ...........................................................................................50
6.8.31 Function Code Errors (22h) ........................................................................................50
6.8.32 Starting Address Errors (23h) .....................................................................................50
6.8.33 Number of Register Errors (24h).................................................................................50
6.8.34 RXD CRC Errors Hi (25h) ...........................................................................................50
6.8.35 RXD CRC Errors Lo (Same as Hi) (26h) ....................................................................50
6.8.36 Parity Errors (27h).......................................................................................................50
6.8.37 Overrun errors (28h) ...................................................................................................51
6.8.38 Framing Errors (29h)...................................................................................................51
6.8.39 Total Software CH1 Errors (2Ah)................................................................................51
6.8.40 New Sensor Calibration (2Bh) ....................................................................................51
6.8.41 Clear Hardware Errors (2Ch) ......................................................................................51
6.8.42 Clear Communication Errors (2Dh).............................................................................51
6.8.43 User Information (60h to 6Fh).....................................................................................55
6.8.44 Total Receive Errors (70h)..........................................................................................55
6.8.45 Bus Activity Rate % (71h) ...........................................................................................55
6.8.46 Function Code Errors (72h) ........................................................................................55
6.8.47 Starting Address Errors (73h) .....................................................................................55
6.8.48 Number of Register Errors (74h).................................................................................55
6.8.49 RXD CRC Errors Hi (75h) ...........................................................................................56
6.8.50 RXD CRC Errors Lo (Same as Hi) (76h) ....................................................................56
6.8.51 Parity Errors (77h).......................................................................................................56
6.8.52 Overrun Errors (78h)...................................................................................................56
6.8.53 Framing Errors (79h)...................................................................................................56
6.8.54 Total software CH1 errors (7Ah).................................................................................56
7.0 APPENDIX............................................................................................................................57
7.1 Warranty...................................................................................................................................57
7.2 Principle of Operation...............................................................................................................57
7.3 Specifications ...........................................................................................................................58

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7.3.1 System Specifications.................................................................................................58
7.3.2 Mechanical Specifications...........................................................................................58
7.3.3 Electrical Specifications ..............................................................................................58
7.3.4 Cable Requirements ...................................................................................................59
7.3.5 Remote Sensor Cable Lengths...................................................................................60
7.3.6 Environmental Specifications......................................................................................60
7.4 Approvals .................................................................................................................................61
7.5 Sensitivities to Other Gases.....................................................................................................61
7.6 Spare Parts and Accessories...................................................................................................63
7.6.1 Sensors .......................................................................................................................63
7.6.2 Sensor Housing...........................................................................................................63
7.6.3 Sensor Accessories ....................................................................................................63
7.6.4 Calibration Equipment.................................................................................................63
7.6.5 S4000CH Replacement Parts.....................................................................................64
7.6.6 Recommended Spare Parts for One (1) Year ............................................................64
7.7 FM Approval.............................................................................................................................65

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Table of Figures
Figure 1: Outline and Mounting Dimensions in inches........................................................................................... 1
Figure 2: Outline and Mounting Dimensions (ARGC) in inches ............................................................................. 1
Figure 3: Sensor Remote Installation in inches...................................................................................................... 2
Figure 4: ARGC Remote Installation ...................................................................................................................... 2
Figure 5: Spring Type Terminal Block Operation ................................................................................................... 3
Figure 6: Screw Type Terminal Block Operation.................................................................................................... 3
Figure 7: Model S4000CH Intelligent Sensor ......................................................................................................... 8
Figure 8: Model S4000CH Intelligent Sensor with ARGC ...................................................................................... 9
Figure 9: ARGC Remote Junction Box Assembly (P/N 80155-1) .......................................................................... 9
Figure 10: Outline and Mounting Dimensions in inches....................................................................................... 12
Figure 11: Outline and Mounting Dimensions (ARGC) in inches ......................................................................... 13
Figure 12: S4000CH Terminal Block Locations ................................................................................................... 14
Figure 13: Remote Junction Box Terminal Block ................................................................................................. 14
Figure 14: Spring Type Terminal Block Operation ............................................................................................... 15
Figure 15: Screw Type Terminal Block Operation................................................................................................ 16
Figure 16: Wire Strip Length................................................................................................................................. 16
Figure 17: Relay Protection for DC and AC Loads............................................................................................... 19
Figure 18: Relay Reset......................................................................................................................................... 22
Figure 19: User Menu Structure ........................................................................................................................... 23
Figure 20: Calibration Check ................................................................................................................................ 26
Figure 21: Automatic Calibration Mode ................................................................................................................ 28
Figure 22: Calibration in Progress Mode.............................................................................................................. 28
Figure 23: Calibration Complete Mode................................................................................................................. 28
Figure 24: Remote Gas Calibrator (RGC, P/N 80153-1)...................................................................................... 30
Figure 25: ARGC Gas Control (P/N 80154-1) ...................................................................................................... 30
Figure 26: Calibration Complete Mode................................................................................................................. 32

vii
Model S4000CH
Table of Tables
Table 1: TB2 Power and Signal Connections....................................................................................................... 15
Table 2: Ground or Common Connections........................................................................................................... 17
Table 3: Power Connections ................................................................................................................................ 17
Table 4: Analog Signal Connections .................................................................................................................... 18
Table 5: Alarm Relay Connections....................................................................................................................... 18
Table 6: Warn Relay Connections........................................................................................................................ 18
Table 7: Fault Relay Connections ........................................................................................................................ 19
Table 8: GM Locations.......................................................................................................................................... 36
Table 9: Data Format............................................................................................................................................ 37
Table 10: Exception Codes .................................................................................................................................. 39
Table 11: Com1 Baud Rate .................................................................................................................................. 46
Table 12: Com1 Data Format ............................................................................................................................... 46
Table 13: Current Chart........................................................................................................................................ 47
Table 14: Com2 Baud Rate .................................................................................................................................. 48
Table 15: Com2 Data Format ............................................................................................................................... 48
Table 16: 24 VDC Cable Lengths with Relays ..................................................................................................... 59
Table 17: 24 VDC Cable Lengths w/o Relays...................................................................................................... 59
Table 18: ARGC Cable Lengths........................................................................................................................... 60
Table 19: Analog Output Cable Lengths .............................................................................................................. 60
Table 20: Sensor Cable Lengths.......................................................................................................................... 60
Table 21: Chemical List ........................................................................................................................................ 62

Model S4000CH
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Quick Start Guide
Mounting and Wiring
Tools Required
“5mm” Allen head wrench to remove enclosure lid (included with gas detector).
Flat-head screwdriver maximum 3/16” (5 mm) width for terminal block connections
(included with gas detector).
Adjustable wrench for conduit or cable gland connections (not included).
Information on Class I Division 1 and Zone 1 wiring methods can be found in the NEC and
CEC.
Figure 1: Outline and Mounting Dimensions in inches
Figure 2: Outline and Mounting Dimensions (ARGC) in inches

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Figure 3: Sensor Remote Installation in inches
Figure 4: ARGC Remote Installation

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Ground
+24 VDC
Terminal Connections
The terminal blocks (TB) are located inside the housing and can be accessed by removing the
cover. A label on the inside of the housing cover provides details of all the terminal
connections.
WARNING: Do not connect +24 VDC to TB1. Damage to the electronics or sensor may
result.
It is recommended that a minimum three-wire shielded cable be used for making the power
and 0-20mA Output connection on TB2 of the S4000CH. It is also recommended that separate
two-wire shielded twisted pair cables be used for making the Modbus connections. The spring
type terminal block accepts 14 AWG to 20 AWG and the screw type terminal block accepts 12
AWG to 18 AWG stranded or solid wire. Each wire should be stripped before wiring the
S4000CH intelligent sensor. To connect wiring to the spring type terminal block, insert a
screwdriver into the orange tab and press down (Figure 5), opening the terminal. Insert the wire
into the terminal and release the orange tab, clamping the wire in the terminal. Check the hold
of the wire by GENTLY tugging it to ensure it is locked in.
Figure 5: Spring Type Terminal Block Operation
To connect wiring to the screw type terminal block, (Figure 6) use a screwdriver to loosen the
top screw counter clockwise. Insert the wire into the terminal and tighten the top screw
clockwise. Check the hold of the wire by GENTLY tugging it to ensure it is locked in.
Figure 6: Screw Type Terminal Block Operation
Ground
+24 VDC

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NOTE: Power must remain disconnected until all other wiring connections have been made.
The maximum distance between the S4000CH and the power supply is 3430 feet or 1040
meters (each cable run should be as short as possible). See Section 7.3.4 for cable length
specifications.
Connect +24 VDC to TB2, position 9. Connect the ground or common to TB2, position 8.
To connect the analog signal, please refer to Section 3.5.4.
General Monitors recommends that the S4000CH Intelligent Sensor be calibrated one hour
after start-up, and that the calibration be checked at least every ninety (90) days to ensure
system integrity.
The instrument is now ready to operate. Please consult the manual for more information on the
instrument’s many features.
NOTE: If you have any problems in the set-up or testing of the detector, please refer to the
“Troubleshooting Section”, or call the factory direct. See Section 5.2.

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1.0 Introduction
1.1 Protection for Life
General Monitors’ mission is to benefit society by providing solutions through industry leading
safety products, services, and systems that save lives and protect capital resources from the
dangers of hazardous flames, gases, and vapors.
This manual provides instruction for installing and operating General Monitors’ Model
S4000CH for combustible gas detection. While the S4000CH is easy to install and operate,
this manual should be read in full and the information contained herein understood before
attempting to place the system in service.
The safety products you have purchased should be handled carefully and installed, calibrated,
and maintained in accordance with the respective product instruction manual. Remember
these products are for your safety.
1.2 Special Warnings
The Model S4000CH Intelligent Sensor contains components, which can be damaged by
static electricity. Special care must be taken when wiring the system to ensure that only the
connection points are touched.
WARNING: Toxic, combustible and flammable gases and vapors are very dangerous. Extreme
caution should be used when these hazards are present.
DO NOT OPEN WHEN AN EXPLOSIVE ATMOSHPERE IS PRESENT.
READ AND UNDERSTAND INSTRUCTION MANUAL BEFORE
OPERATING OR SERVICING. OPEN CIRCUIT BEFORE REMOVING
COVER. POTENTIAL ELECTROSTATIC CHARGING HAZARD – USE
ONLY DAMP CLOTH FOR CLEANING.
NE PAS OUVRIR UN PRÉSENCE D’ATMOSPHÉRE EXPLOSIVE. LIRE
ET COMPRENDRE MANUEL D’INSTRUCTIONS AVANT D’UTILISER OU
SERVICE. OUVRIR LE CIRCUIT AVANT D'ENLEVER LE COUVERCLE.
DANGER POTENTIEL ÉLECTROSTATIQUE DE CHARGE –
UTILISATION UNIQUEMENT UN CHIFFON HUMIDE POUR LE
NETTOYAGE.
SPECIAL CONDITIONS OF SAFE USE PERTAINING TO ATEX/IECEx INSTALLATIONS:
The S4000CH has been subjected to performance testing in accordance with EN 60079-29-1
and therefore may be used as a safety related device as defined by ATEX Directive 94/9/EC
Annex II clause 1.5.
When alternative detector elements are utilized, they shall only be mounted remotely in a
suitable certified enclosure in accordance with requirements of their respective certificates and
relevant local requirements. The associated cable shall be connected to the Intelligent Gas
Sensors using a suitably certified cable entry device with a ¾” thread form.
The Universal Gas Sensor (11159-XX) is suitable for use with the following enclosure types
and service/temperature ranges that are dependent on the type of cement used in their

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construction; therefore, they shall only be used with the enclosure type and where the surface
temperature, at the point of mounting, is as detailed below:
Cement Ambient Range Enclosure Type
2850FT Cat 11,
2762 Cat 17
-40°C to +70°C Enclosures that are certified by a notified body and
satisfy the requirements of the current edition of EN
60079-1 or EN 60079-7 and European Directive
94/9/EC.
2850FT Cat 11 -40°C to +120°C Enclosures that are certified by a notified body and
satisfy the requirements of the current edition of EN
60079-7 and European Directive 94/9/EC.
2762 Cat 17 -40°C to +180°C Enclosures that are certified by a notified body and
satisfy the requirements of the current edition of EN
60079-7 and European Directive 94/9/EC.
The Universal Gas Sensor (11159-XX), when tested in accordance with clause 15.4.2.1 of EN
60079-1, produced a maximum surface rise of 26.3 K. This value should be considered when
the component is incorporated into equipment.
The Universal Gas Sensor (11159-XX), utilizing Types 2850FT Cat 11 and 2762 Cat 17
cement shall only be fitted to enclosures having a maximum reference pressure of 9.6 bar.
1.3 System Integrity Verification
Commissioning Safety Systems
Before power up, verify wiring, terminal connections and stability of mounting for all integral
safety equipment including, but not limited to:
Power supplies
Control modules
Field detection devices
Signaling / output devices
Accessories connected to field and signaling devices
Remote Gas Calibrator (RGC) / Automatic Remote Gas Calibrator (ARGC)
After the initial application of power (and any factory specified warm-up period) to the safety
system, verify that all signal outputs, to and from devices and modules, are within the
manufacturer’s specifications. Initial testing should be performed per the manufacturer’s
recommendations and instructions.
Proper system operation should be verified by performing a full, functional test of all
component devices of the safety system, ensuring that the proper levels of alarming occur.
Fault/Malfunction circuit operation should be verified.

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Periodic Testing of Field Devices
Periodic testing/calibrating should be performed per the manufacturer’s recommendations and
instructions. Testing/calibrating procedures should include, but not be limited to:
Verify integrity of all optical surfaces and devices
When testing produces results outside of the manufacturer’s specifications, replacement of the
suspect device(s) should be performed as necessary. Maintenance intervals should be
independently established through a documented procedure, including a maintenance log
maintained by plant personnel or third party testing services.
Periodic System Verification
The following system verifications should be performed at least annually:
Verify wiring, terminal connections and stability of mounting for all integral safety equipment
including, but not limited to:
Power supplies
Control modules
Field detection devices
Signaling / output devices
Accessories connected to field and signaling devices
RGC or ARGC (if purchased)

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2.0 Product Description
2.1 General Description
The Model S4000CH is an intelligent sensor for the detection of combustible gases and
vapors. The microprocessor-based electronics process information at the sensor site within
an explosion-proof housing.
A digital display provides indications and display codes that can be viewed through a window
in the cover. A red LED above the digital display signifies an ALARM condition, while a red
LED below the digital display signifies a WARN condition. Analog signal (4-20 mA) and relays
provide remote and/or discrete indications of the sensor’s operation. Optional dual redundant
Modbus, HART or HART and single Modbus provide digital communication.
The Model S4000CH Intelligent Sensor is rated explosion-proof for use in the following
hazardous areas:
CSA/FM: Class I, Division 1, Groups B, C, D and Class I, Zone 1, IIB+H2
ATEX/IECEx: Zone 1, Group IIB + H2 and Zone 21, Group IIIC
Figure 7: Model S4000CH Intelligent Sensor
NOTE: The image in Figure 7 is for reference only. See section 7.3 for actual product
specifications.

Model S4000CH
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Figure 8: Model S4000CH Intelligent Sensor with ARGC
NOTE: The image in Figure 8 is for reference only. See section 7.3 for actual product
specifications.
Figure 9: ARGC Remote Junction Box Assembly (P/N 80155-1)

Model S4000CH
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3.0 Installation
3.1 Receipt of Equipment
All equipment shipped by General Monitors is pre-packed in shock absorbing containers,
which provide protection against physical damage (original containers should be kept for
future shipping or storage needs).
Shipping container contents should be carefully removed and checked against the packing
list. If any damage has occurred, or there is any discrepancy in the order, please notify
General Monitors as soon as possible.
All correspondence with General Monitors must specify the equipment part number and serial
number.
The factory tests each unit; however, a complete system checkout is suggested upon initial
installation to ensure system integrity.
WARNING: Installation and maintenance must be carried out by suitably skilled and
competent personnel only.
3.2 Tools Required
“5 mm” Allen head wrench to remove enclosure lid (included with gas detector).
Flat-head screwdriver maximum 3/16” (5 mm) width for terminal block connections
(included with gas detector).
Adjustable wrench for conduit or cable gland connections (not included).
3.3 Choosing Product Locations
There are no standard rules for sensor placement, since the optimum sensor location is
different for each application. The customer must evaluate conditions at the facility to make
this determination. Generally, the Model S4000CH Intelligent Sensor should be easily
accessible for calibration checks.
The sensor should be mounted pointing down to prevent water build-up on the
sensor head.
The sensor should not be placed where contaminating substances may coat it.
Although the S4000CH is RFI resistant, it should not be mounted in close proximity to
radio transmitters or similar equipment.
Locate the S4000CH where prevailing air currents contain the maximum
concentration of gas.
Locate the S4000CH near possible sources of gas leaks.
Observe the S4000CH’s temperature specification and locate the unit away from
concentrated sources of heat.

Model S4000CH
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Sensors should be mounted in an area that is as free from wind, dust, water, shock,
and vibration as possible. See Section 7.3.6 for the environmental specifications of
the unit. If the sensor cannot be located away from dust and rain, then we
recommend the use of our splashguard GM P/N 10395-1 to help protect the sensor.
Sensors may be adversely affected by prolonged exposure to certain materials. Loss of
sensitivity or corrosion may be gradual if such materials are present in low concentrations, or
it may be rapid at high concentrations. The more important materials adversely affecting
sensors are:
Constant presence of high concentrations of hydrogen sulfide (H2S) gas
Silicones (often contained in greases and aerosols)
Halides, compounds containing fluorine, chlorine, bromine and iodine
Heavy metals, e.g. tetraethyl lead
Caustic and acidic liquids and vapors
The presence of poisons and contaminants in an area does not necessarily preclude the use
of a Model S4000CH intelligent sensor. The feasibility of using a sensor in such areas must
be determined by an analysis of the specific factors in each application and General Monitors
should be consulted before attempting any such installation.
Sensors used in these areas usually require more frequent calibration checks than normal,
and typically have a shorter life. In many such applications, the standard two-year warranty
would not apply.
WARNING: General Monitors discourages the painting of sensor assemblies. If the sensor
head is painted over, the gas will not be able to diffuse into the sensor. If the
assembly cover is painted over, the digital display cannot be read.
3.3.1 Remote Mounting of the Sensor from the Electronics
If it is necessary to remotely mount the sensor from the electronics and the housing, the
sensor must be mounted in an explosion-proof rated sensor housing (GM P/N 10252-1 or
10252-3). The 10252-3 sensor housing can be used at temperatures up to 200°C when
used with sensor 11159-2. The cable run must be contained in conduit running from the
sensor housing to the electronics. See Section 7.3.4 for cable lengths. The maximum
cable length to the power supply will be reduced by 10%.
For remote mounting in Canada where the location is classified using the Zone
classification system, the sensors must be mounted in sensor housing B13-020, B13-021,
or B13-022 as applicable. Only sensors 11159 can be used in this configuration.
General Monitors has accessories that help with remote or difficult to get to locations. The
RGC or ARGC facilitate remote gassing.
NOTE: At an upper ambient of +200°C, the accuracy of the gas readings will be negatively
impacted. For example, in an atmosphere of 10% LEL gas, the sensor will read
approximately 2% LEL; at 25% LEL, the sensor will read approx.15%; at 50% LEL,
the sensor will read approx. 34%; at 75% LEL, the sensor will read approx. 59%, at
85% LEL, the sensor will read approx. 67%.

Model S4000CH
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3.4 Mounting and Wiring
WARNING: Unused cable entry holes must be sealed with a suitably certified ATEX or
IECEx explosion-proof stopping plug. Red caps supplied by General Monitors
are for dust protection only, and must not be left on the unit when installed.
WARNING: Conduits must be sealed within 18 inches of the enclosure.
The outline and mounting dimensions for the S4000CH (Figure 10) should be used when
making installation determinations. A complete list of the mechanical specifications can be
found in Section 7.3.2.
To prevent possible corrosion due to moisture or condensation, it is recommended that the
conduit connected to the S4000CH housing contain a drain loop.
NOTE: For ATEX and IECEx applications, conduit connections must only be made via
suitably certified ATEX (or IECEx as appropriate) conduit stopping boxes.
Information on Class I Division 1 and Zone 1 wiring methods can be found in the NEC and
CEC.
WARNING: Acetic acid will cause damage to metal components, metal hardware, ceramic
IC’s, etc. If damage results from the use of a sealant that outgases acetic acid
(RTV silicone), the warranty will be void.
Figure 10: Outline and Mounting Dimensions in inches