MSA 610A User manual

Model 610A
Four Channel Control Module
Combustible Gas Applications
The inf ormation 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 07-21
General Monitors reserves the right to change
published specifications and designs without
prior notice.
Part No MAN610A
Revision H07-21
CR 800000051894

ii
This page intentionally left blank.

MODEL 610A
iii
Table of Contents
MODEL 610A........................................................................................................................... I
FOUR CHANNEL CONTROL MODULE................................................................................... I
COMBUSTIBLE GAS APPLICATIONS.................................................................................... I
ILLUSTRATIONS...................................................................................................................VI
LIST OF TABLES................................................................................................................. VII
INTRODUCTION..................................................................................................................... 1
Protection for Life..................................................................................................................1
Sp ec ial Warning....................................................................................................................1
Customer Support......................................................................................................2
1.0 BEFORE INSTALLATION................................................................................................. 3
1.1 Differences Between Models 610A and 610...................................................................3
1.2 General Product Description........................................................................................3
1.3 Controller..................................................................................................................4
1.4 S e nso r A ss emb ly .......................................................................................................5
2.0 INSTALLATION................................................................................................................ 6
2.1 Location of the Controller............................................................................................6
2.2 Power Connections ....................................................................................................6
2.3 Battery Backup..........................................................................................................7
2.4 Analog Output Connection ........................................................................................11
2.5 Remote Reset Connection ........................................................................................11
2.6 Choosing Sensor Locations.......................................................................................11
2.6.1 V apo r D ens it y ..............................................................................................11
2.6.2 Air Currents .................................................................................................11
2.6.3 Likely Sources of Gas Emission......................................................................11
2.6.4 Environmental Factors...................................................................................12
2.6.5 Catalytic Poisons..........................................................................................12
2.7 Sensor Installation ...................................................................................................12
2.8 Alarm Wiri ng Co nnec tio ns .........................................................................................15
2.9 Special Voting Option...............................................................................................16
3.0 START-UP AND OPERATION........................................................................................ 18
3.1 Types of User Interf aces ...........................................................................................18
3.2 Initial Application of Power ........................................................................................19
3.3 Resetting Latched Alarms .........................................................................................19
3.4 Analog Output .........................................................................................................19
3.5 Calibration Check Mode............................................................................................20
3.6 Calibration Mode......................................................................................................21

MODEL 610A
iv
3.6.1 Aborting Calibration ......................................................................................21
3.7 S e t up and S et up Check Mod es ..................................................................................22
3.7.1 Entering the Password ..................................................................................23
3.7.2 Hi g h Al arm Opt io ns .......................................................................................23
3.7.3 Low Alarm Options .......................................................................................23
3.7.4 Calib ration Level Option.................................................................................24
3.7.5 Password Enabled/Disabl ed Opt io n.................................................................24
3.7.6 LED Test.....................................................................................................24
3.8 Setup Mode Selection Table......................................................................................25
3.9 Check Points for Calibration and Operation..................................................................26
3.9.1 Frequency of Calibration................................................................................26
3.9.2 Background of Combustible Gases..................................................................26
3.9.3 Rep l ac i ng a S enso r.......................................................................................26
3.10 Special Options.......................................................................................................26
3.10.1 Optional Model 610A Controller for Zone Control (Voting)...................................26
3.10.2 Set Up Options.............................................................................................27
4.0 MAINTENANCE.............................................................................................................. 28
4.1 General Maintenance...............................................................................................28
4.2 P eriod ic Sys tem Verificat io n ......................................................................................28
5.0 TROUBLESHOOTING .................................................................................................... 29
5.1 General..................................................................................................................29
5.2 Troubleshooting Table..............................................................................................29
5.3 Fault Codes ............................................................................................................30
6.0 CUSTOMER SUPPORT .................................................................................................. 31
6.1 General Monitors’ Offices..........................................................................................31
6.2 Other Sources of Help ..............................................................................................31
7.0 APPENDIX...................................................................................................................... 32
7.1 Warranty ................................................................................................................32
7.2 S e nso r Op erat i ng P rinc iple........................................................................................32
7.3 General Specifications - Controller..............................................................................34
7.3.1 Mechanical Specifications..............................................................................34
7.3.2 Environmental Specific atio ns..........................................................................34
7.3.3 E lec tric al Specif ic at io ns .................................................................................34
7.3.4 S yst em Sp ecif icatio ns ...................................................................................34
7.4 General Specifications - Sensor.................................................................................34
7.4.1 System Specif icat io ns ...................................................................................34
7.4.2 Environmental Specifications..........................................................................34
7.5 Cable Requirements.................................................................................................35
7.6 S enso rs..................................................................................................................35
7.7 Accessories ............................................................................................................36
7.7.1 Calibration Equipment ...................................................................................36
7.7.2 Sensor Covers .............................................................................................36
7.8 Recommended Spare Parts.......................................................................................37
7.9 Sample Calibration Schedule and Checklist .................................................................38
7.10 Engineering Documentation.......................................................................................40

MODEL 610A
v
7.10.1 Panel Assembly, Panel Mount – 98, Ref: 10199C..............................................40
7.10.2 Interconnec tion Drawing Zone Control Model 610A Controller .............................41

MODEL 610A
vi
Il l us t rat io nsFigure 1: Model 610A Controller ..............................................................................4
Figure 2: Sc hem at ic B at t ery B ack up Sy st em .............................................................................7
Figure 3: Outline Drawing & Rear Terminal Connections (REF: 20659) .........................................8
Figure 4: Rear Terminal Common Relay Configuration................................................................9
Figure 5: Rear Terminal Discrete Relay Configuration...............................................................10
Figure 6: Junc tion Box Assembly – S enso r .............................................................................14
Figure 7: Protection Circuit for Relay Contacts.........................................................................16
Figure 8: F ro nt P anel D isp lay ................................................................................................18
Figure 9: Portable Purge Calibrator........................................................................................20
Figure 10: Panel Assembly, Panel Mount –98, Ref: 10199C ......................................................41
Figure 11: Interconnection Drawing Zone Control Model 610A Controller.....................................41

MODEL 610A
vii
List of Tables
Table 1: Model 610A Mounting Parts........................................................................................6
Tab le 2: Terminal Colors ......................................................................................................13
Table 3: Maximum Cable Run Distance..................................................................................13
Table 4: Sensor Guards .......................................................................................................15
Table 5: De-Energized Alarm Relay Contacts ..........................................................................15
Table 6: Energized Alarm Relay Terminations .........................................................................15
Table 7: S et up D isp lay Opt io ns .............................................................................................25
Table 8: Relay Alarm Options................................................................................................27
Tab le 9: Tro ub les hoo ting Tab l e .............................................................................................30
Tab le 10: Max im um Cab l e Leng t hs ........................................................................................35
Table 11: GMI Sensors Available for 610A System...................................................................35
Table 12: Recommended Spare Parts....................................................................................37
Table 13: Prod uct Configuration Tables ......................................... Error! Bookmark not defined.

MODEL 610A
1
Introduction
Protection for Life
General Monitors’ mission is to benefit society by providing solutions through industry
leading saf ety 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 the General Monitors Model
610A Four Channel Control Module for Combustible Gas Applications. While t he 610A
system is easy to install and operate, this manual should be read in f ull and the
inf ormation contained herein understood bef ore attempting to place the system in
service.
The saf ety 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 f or your safety.
Special Warning
Through engineering design, testing, manufacturing techniques, and rigid quality control,
General Monitors (GMI) supplies the finest gas detection system s av ail abl e. The us er
must recognize his responsibility for maintaining the gas detection system in operational
condition.
The Model 610A Four Channel Combustible Gas Monitor contains com ponent s, 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.
Only catalytic bead sensors designed by General Monitors will work with the Model 610A
Controller. Any attempt to use a sensor that has not been approved by General Monitors,
will void the warranty.
General Monitors cautions, as with all equipment of this type, that high levels or long
exposure to certain atmospheres will “poison” the sensor catalyst and eventually affect
sensitivity. Please see Section 2.6.5 for specific information. Use in s uch at mos pheres
requires calibration checks on a more frequent schedule than normal. General Moni tors
should be consulted for an application feasibility determination, before installing a system
in such atmospheres.
General Monitors’ sensors and sensor housings are designed and tested f or use in
certain classes of hazardous atmospheres. Explosion-proof integrity cannot be
maintained, if sensors and sensor housings are operated in other than the “as designed”
condition. Terminal access covers of sensor housings must be securely fastened. Sensor
housing must be installed in accordance with National Electrical Code acceptable
practices, for the class of hazardous atmospheres.

MODEL 610A
2
Sensors are designed with sintered metal, or screen covers, that act as flame arres t ors.
Do not operate sensors without screen or sintered metal parts in place.
General Monitors’ gas detection systems are primarily safety devices for the protection of
personnel and facilities and must be “always ready”. With proper installation, calibration,
and maintenance, the system provides continuous monitoring of hazardous areas. The
user must assume all liability for misuse of General Monitors’ gas detection systems.
The system’s full two-year warranty will be voided if customer personnel, or third parties,
damage the system during repair attempts.
Customer Support
For additional product information not contained in this manual, please contact General
Monitors Customer Support (Section 6.1).

MODEL 610A
3
1.0 Before Installation
1.1 Differences Between Models 610A and 610
610A differences:
•Wiring: Connectors must be rewired for 610A
•Auto-Calibration
•Front Panel: Polycarbonate with inlay
Ref er to Section 2.0, Installation, and Section 3.0, Startup and Operation, for details.
1.2 General Product Description
The Model 610A Controller is a four-channel system designed to continuously monitor for
potential explosive concentrations of most combustible gases/vapors. Normall y, onl y a
periodic calibration check is needed to assure dependable performance. The system
operates in the range of 0-100% LEL (Lower Explosive Limit) and is calibrated f or a
particular gas or vapor. There are relatively few combustible gases, which should not be
monitored; however, as a precaution, GMI should always be consulted to verif y the
f easibility of monitoring any gas or vapor other than those specif ied at the time of
purchase.
The Model 610A Controller consists of a controller plus four sensor assemblies. The
controller is fully solid-state. It should be mounted in a weather protected, non-hazardous
area. Several GMI mounting accessories are available for panel, wall or 19-inch rack
installation. For hazardous areas, an explosion-proof housing is available for Class I,
Division 1 and Division 2, Groups B, C & D.
NOTE: Sensor assemblies may be mounted outdoors in hazardous areas
(National Electric Code Class I, Division 1 and Division 2, Groups B, C & D).
GMI catalytic bead sensors must be connected to the controller in accordance with the
installation instructions in this manual.
NOTE: The 610A is dif f erent than its predecessor the 610. The 610A calib ration is
automatic where the 610 must be manually calibrated. Please check the
individual manuals for details about wiring, set up and operat io n of t hese t wo
units.

MODEL 610A
4
CAUTION: The Model 610A Controller is easy to install and operate. However, one
should fully read and understand this manual before attempting to place t he
system in service.
Figure 1: Model 610A Controller
1.3 Controller
The Model 610A Controller is a four-channel system where the controller continuously
monitors the inputs of four sensors. The sensors are monitored independently (i.e. they
are not scanned, nor are the signals summed).
Each channel has the following:
•Constant current sensor drive circuit
•LED indicators for High, Low, Fault, Calibration, and Setup
•Mode Button, accessed by using a small screw driver
•Digital Display in %LEL
•High, Low and Fault relays

MODEL 610A
5
NOTE: Standard configuration is common relays (Figure 4).
Set points for High and Low alarms are adjustable from 5to 60% LEL in the FM unit.
NOTE: A service-loop is necessary between the Model 610A Cont roller’s rear p anel
terminals and field/power wiring. This service loop permits the controll er t o be
removed or slid forward for various adjustments and/or servicing. This is a
def inite advantage when replacing or changing a controller.
1.4 Sensor Assembly
Four sensor assemblies are normally supplied with the system. Thes e as sembli es are
comprised of the sensor, the sensor housing, and an optional splashguard.
NOTE: This sensor assembly is FM and CSA approved for Class I, Division 1 and
Division 2, Groups B, C & D hazardous areas.
On some occasions, different sensor housings may be supplied. The appropriate sensor
is provided if GMI is made aware of the gas or vapor that is to be monitored. Most
combustible gases may be monitored, including most hydrocarbons and hydrogen.
CAUTION: Sensors have a different sensitivity to each gas. GMI should be consulted i f
a sensor is expected to detect more than one gas. GMI can then
recommend the best calibration gas.
A variety of sensor covers may be purchased (Section 7.7.2). They provide extra
protection from wind, weather and dust.
NOTE: These sensor covers are not included in the Factory M ut ual ap proval f or t hi s
equipment.
In the event the system is to have less than four active channels, Part Number 10102-1
(sensor simulator) must be substituted for each unused channel. Otherwise, the FAULT
LED indicator for the unused channel will remain lit.

MODEL 610A
6
2.0 Installation
2.1 Location of the Controller
The Model 610A Controller should be installed in a weather-protected, non-hazardous
area. The f ollowing mounting hardware is available to facilitate installation:
Part Description
Part Number
98mm (4”) panel mount frame
P/N 10199-1
483 mm (19”) rack f rame (4 controllers)
P/N 10200-1
Blank panel (one for each unused position in 19” f rame)
P/N 10191-1
98mm (4”) wall mount bracket
P/N 10202-1
Table 1: Model 610A Mounting Parts
The f ollowing are guidelines for mounting the controller:
•To minimize the possibility of electrical shock, mounting must be as free from
shock and vibration as possible, in a grounded enclosure that requires a tool f or
instrument removal.
•Even though the controller is RFI resistant, do not mount the controller in c lose
pro x imit y to radio transmitters or similar equipment.
•It is recommended that a wiring service loop be used to facilitate gaining ac cess
to the alarm set points.
•Care should be taken to assure adequate ventilation.
•Do not mount the controller in a manner that restricts the natural convection
airflow.
•The controller operating temperature range is 0°C to 60°C (32°F to 140°F).
2.2 Power Connections
The system operates on nominal line power of 115 VAC, 50/60 Hz. Power mus t remain
disconnected until all other wiring connections are made.
NOTE:To eliminate accidental system shutdown, GMI does not provide a power on/off
switch.
The f ollowing are wiring guidelines for the 610A Controller:
•If AC is to power the system, connect the line power supply to the terminals L, N,
located on the rear of the controller. Use accepted commercial wiring practices.
•Primary DC power may be used instead. Use any 24V no mi nal direct current
supply with a minimum rating of 2 amperes.
•AWG 14 wire should be used to prevent excessive voltage drop.

MODEL 610A
7
•Wiring runs should be as short as possible.
•Connect the positive supply to 24VDC (+) and the negative supply to 24VDC (-)
on the terminal block. An internal diode protects the system in case of
inadvertent supply reversal.
2.3 Battery Backup
An emergency battery backup may be employed on a system normally powered b y AC.
The battery rating (ampere-hour capacity) is dictated by the length of time power outages
may last. A Model 610A Controller requires approximately 2 ampere (peak ) at 24 VDC.
General Monitors recommends that a Lead-Acid type battery be used. This type of
battery can be expected to last for several years with minimum maintenance.
The customer-furnished battery may be connected as shown below. Manual or relay
switching is not required. There is no provision for battery charging. A customer furnished
battery charger must be used to keep the battery charged to the battery manuf act urer’s
recommended level. The cable length from battery to controller s houl d be as short as
possible. Should an AC power failure occur, the 24-Volt battery supplies current through
the diode to the controller circuitry. DO NOT USE MORE THAN A 24-VOLT BATTERY.
Figure 2: Schematic Battery Backup System

MODEL 610A
8
Figure 3: Outline Drawing & Rear Terminal Connections (REF: 20659)

MODEL 610A
9
Figure 4: Rear Terminal Common Relay Configuration

MODEL 610A
10
Figure 5: Rear Terminal Discrete Relay Configuration

MODEL 610A
11
2.4 Analog Output Connection
CAUTION: The analog output must be either used or jumpered. If not, the Model 610A
indicates a fault in the normal mode with the display read i ng “AO” and the
FAULT LED f lashing.
The two analog output terminals A O (+) and AO (-) are located on the rear panel. The
analog output is 0 – 21.7mA into a maximum 300-Ohm load.
2.5 Remote Reset Connection
Remote reset (of alarm circuits) connections are made to rear panel terminal board
connections RESET and the 24VDC (-) terminal. If a remote reset switch is used, it must
be a “normally open, momentary action” type.
NOTE: If the system is to be powered from a primary DC power supply or if battery
backup is provided, the 24VDC (-) terminal has two wires when remote res et is
used. The diameter of the two wires cannot be larger than an AWG 14 wire.
2.6 Choosing Sensor Locations
Several variables are involved in selecting locations to install sensors, to assure the
detection of combustible gases. There are no hard and fast rules defining t he o ptimum
location. However, the following general suggestions should be considered with regard to
particular conditions at the site where a Model 610A Controller is being installed.
2.6.1 Vapor Density
Whether the gas/vapor to be monitored is lighter or heavier t han air, it af f ects sensor
placement. For lighter-t han-air gases, sensors are generally placed close to the roof or
ceiling in indoor installations. For gases much heavier thanair, sensors are generally
placed near the floor or ground where there are no air currents in the area. Gases with a
density equal to air or slightly greater than air tend to rise, particularly when ai r c urrent s
are present.
2.6.2 Air Currents
If there are winds, fans, or other sources of air movement, combustible gases tend to rise
or to accumulate in certain sections of a facility. Local air currents should be s tudied to
aid in selection of sensor locations.
2.6.3 Likely Sources of Gas Emission
In general, at least one sensor should be located in close proximity to each point where a
leak of a combustible gas is likely to occur. This is particularly important when a liquid
having a high volatility is to be monitored.

MODEL 610A
12
2.6.4 Environmental Factors
Avoid installing sensors where they are exposed to wind, dust, water, shock, or vibration.
Observe the temperature range limitations of sensors (Section 7.4.2).
2.6.5 Catalytic Poisons
Sensors are adversely affected by prolonged exposure t o c ertain m aterial s. Loss of
sensitivity (i.e. reduced response to combustible gases), 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:
•Halides (compounds containing chlorine, fluorine, bromine, or iodine).
•Sulf ur compounds such as SO2(Sulfur Dioxide), H2S (Hydrogen Sulf ide), CS2
(Carbon Disulfide).
•Heavy metals such as tetraethyl lead.
•Silicones (often contained in greases and aerosols). Silicones do not chemicall y
attack the sensor. They, instead, coat the beads and, therefore, reduce or stop
the oxidation of the combustible gas at the catalytically active bead.
•Acid vapors.
•Caustic liquids or vapors.
The presence of such materials in an area does not necessarily prec lude t he us e of a
catalytic bead sensor. The f easibility of using a sensor in such areas must be determined
by an analysis of the specific factors in each application. However, sensors used in s uch
areas usually require calibration checks on a more f requent basis and t ypically have a
shorter life than normal. In many such applications, the normal two-year warranty does
not apply.
CAUTION: General Monitors discourages the painting of sens or ass embl ies f or t wo
reasons. First, if the sensor head is painted-over, gas will not be able to
dif fuse into the sensor. Second, many paints contain lead, which can poison
a sensor.
2.7 Sensor Installation
Various types (P/N’s) of sensors can be provided with the Model 610A Controller.
However, the installation method is identical in all cases. Please refer to Section 7.6.
The sensor assembly is used most often. It consists of P/N 10001-1 or 10058-1 sensor
plus GMI P/N 10252-1 Sensor Housing.
This assembly (P/N 10001-1 or 10058-1 + P/N 10252-1) is FM and CSA approved for
NEC Class I, Division 1 and Division 2, Groups B, C and D hazardous areas.
Each sensor assembly is connected to the controller using 3-conductor stranded cable,
and must be installed with conduit in hazardous areas. Total loop-resistance, ex cl uding
the sensor, must not exceed 40 Ohms. A separate cable is required for each sensor.

MODEL 610A
13
General Monitors recommends the use of shielded cable generally, though in some
cases it is not an absolute necessity. Due to the low levels of sensor signal voltages,
shielded cable is required in some installations to guard against extraneous electrical
noise. The shield must be enclosed in a suitable insulat ing o uter jac ket and must b e
grounded only at the rear-panel sensor-shield ground terminal. Care must be taken to
assure that the shield does not contact the sensor housing or metal conduit.
CAUTION: Avoid running sensor cables close to high power cables, radio transmission
lines, or cables subject to pulses of high current.
Sensor cable connections must be crimped and SOLDEREDfor stable operation. Use
only continuous, un-spliced cable runs if possible. Improperly spliced cable can res ul t i n
corrosion, resistance changes, and drift.
To Connect the Cable at the Sensor:
1. Remove the P/N 10252-1 housing lid to reveal the terminal strip. The sensor is
connected in the housing according to the color designations. (The green
position is not used).
2. Sensor cables are connected at the controller to the terminal blocks located
along the top of the rear of the controller. The channel numbers (1,2,3 & 4) read
f rom right to left on these sets of terminals.
3. Connect the cable so that the terminal color at the sensor housing matches the
terminal color at the controller as follows:
WIRE COLOR
TERMINAL NUMBER
CH4
CH3
CH2
CH1
Black
B1
B1
B1
B1
Red
R2
R2
R2
R2
White
W3
W3
W3
W3
Table 2: Terminal Colors
4. Cable runs should not exceed the following distances (maximum loop resistance
of 40-Ohms):
AWG
METERS
FEET
20
580
1900
18
910
3000
16
1460
4800
14
2320
7600
Table 3: Maximum Cable Run Distance