MSA Zero Two Series User manual

Model 4802A
Zero Two Series Control Module
The inf ormation and technical data disclosed in
this document may be used and d is seminated
only f or the purposes and to the extent
specif ically authorized in writing by General
Monitors.
Instruction Manual 08-21
General Monitors reserves the right to change
published specif ications and designs without
prior notice.
Part No. MAN4802A
Revision J/08-21
CR: 800000049951

Model 4802A
ii
Table of Contents
MODEL 4802A ..................................................................................................................................I
WARRANTY STATEMENT.....................................................................................................VI
Special Warnings................................................................................................................. vi
Syst em Int eg rity Verif ic at io n ..................................................................................................vii
1.0 QUICK-START GUIDE .....................................................................................................IX
1.1 Control Module Installation......................................................................................... ix
1.2 Rear Terminal Connections......................................................................................... x
1.3 Sensor Connections ................................................................................................. xi
1.4 Applying Power........................................................................................................ xi
2.0 INTRODUCTION................................................................................................................1
2.1 General Description................................................................................................... 1
2.2 Features & Benefits ................................................................................................... 2
2.3 App l ic at io ns .............................................................................................................. 3
3.0 INSTALLATION.................................................................................................................4
3.1 Upon Receipt of Equipment ........................................................................................ 4
3.2 Control Module Installation.......................................................................................... 4
3.3 Rear Terminal Connections......................................................................................... 5
3.3.1 A2 Alarm....................................................................................................... 6
3.3.2 A1 Alarm....................................................................................................... 6
3.3.3 Fault Alarm ................................................................................................... 7
3.3.4 Other Open Collector Outputs .......................................................................... 8
3.3.5 Sensor Connections ....................................................................................... 9
3.3.6 Card Test Switch............................................................................................ 9
3.3.7 Analog Output Signal.................................................................................... 10
3.4 S enso r Loc atio n Co ns id erat io ns ................................................................................ 11
3.4.1 General Sensor Location Considerations ......................................................... 11
3.5 Sensor Poisons....................................................................................................... 12
3.6 App ly ing Power....................................................................................................... 12
4.0 OPERATION ...................................................................................................................13
4.1 General Maintenance............................................................................................... 13
4.2 Field Calib ratio n ...................................................................................................... 13
4.3 E l ec tric al Inp uts....................................................................................................... 14
4.4 E l ec tric al Outp uts .................................................................................................... 14
4.5 Accepting Alarm Conditions ...................................................................................... 15
4.6 Resetting Latched Alarms......................................................................................... 16
4.6.1 LED Test .................................................................................................... 16
4.7 CAL/INH Open Collector........................................................................................... 16
4.8 Card Test Feature ................................................................................................... 16
4.9 Fault Diagnostics..................................................................................................... 17
5.0 USER INTERFACES .......................................................................................................19
5.1 Types of User Interf aces........................................................................................... 19

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5.2 Calibration Check Mode ........................................................................................... 20
5.3 Calibration Mode..................................................................................................... 21
5.4 Setup & Setup Check Modes .................................................................................... 25
5.4.1 Entering the Password.................................................................................. 26
5.4.2 Inhibit Mode ................................................................................................ 27
5.4.3 A2 Alarm Options......................................................................................... 28
5.4.4 A1 Alarm Options......................................................................................... 29
5.4.5 Calibration Level Option................................................................................ 31
5.4.6 Fault/Inhibit Option....................................................................................... 32
5.4.7 Card Tes t Opt io ns ........................................................................................ 33
5.4.8 Password Options........................................................................................ 34
5.5 Inhibit Mode............................................................................................................ 35
5.6 Setup Mode Selection Block Diagram......................................................................... 36
6.0 CUSTOMER SUPPORT...................................................................................................37
6.1 General Monitors’ Offices ......................................................................................... 37
7.0 APPENDIX ......................................................................................................................38
7.1 Principle of Operation............................................................................................... 38
7.2 Sp are P arts and Ac c esso ri es .................................................................................... 39
7.2.1 S enso rs ...................................................................................................... 39
7.2.2 S enso r Ho us i ng ........................................................................................... 39
7.2.3 Sp l as h-Guard & TGA-1................................................................................. 40
7.2.4 Dust Guard Assembly................................................................................... 41
7.2.5 Duct Mounting Plates.................................................................................... 42
7.2.6 Calibration Equipment................................................................................... 42
7.2.7 Calibration Check Mode................................................................................ 44
7.2.8 Calibration Mode.......................................................................................... 44
7.2.9 Calibration Check & Calibration Modes............................................................ 45
7.2.10 Calibration Equipment and Part Numbers ........................................................ 45
7.3 S yst em Sp ecif ic atio ns .............................................................................................. 46
7.3.1 Converting Test and Calibration Gas Concentrations for % LFL to % Volume........ 46
7.3.2 Accuracy..................................................................................................... 46
7.3.3 Relative Sensitivities..................................................................................... 47
7.3.4 Poisons and Interfering Gases ....................................................................... 47
7.3.5 Storage...................................................................................................... 47
7.4 Mechanical Specifications......................................................................................... 47
7.5 E lect ric al Specif ic at io ns ............................................................................................ 48
7.5.1 Cable Parameters ........................................................................................ 48
7.6 Environmental Specifications..................................................................................... 49
7.7 Engineering Specif ic at io ns ........................................................................................ 49
7.7.1 Zero Two System......................................................................................... 49
7.7.2 4802A Control Module .................................................................................. 50
7.8 Volatile Liquids and Solvents..................................................................................... 51
7.9 Engineering & Technical Drawings............................................................................. 53
7.9.1 Outline & Terminal Connections ..................................................................... 53
7.9.2 Final Assembly ............................................................................................ 54
7.10 Zero Two Series Modules ......................................................................................... 55

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List of Figures
Figure 1: Control Module Coding Strip ...................................................................................................ix
Figure 2: Wire Strip Length .................................................................................................................. x
Figure 3: Rear Terminal Designations.................................................................................................... x
Figure 4: Sensor/Controller Connections................................................................................................xi
Figure 5: Rear Power Connections.......................................................................................................xii
Figure 6: Model 4802A ........................................................................................................................ 1
Figure 7: Control Module Coding Strip ................................................................................................... 4
Figure 8: Wire Strip Length .................................................................................................................. 5
Figure 9: Rear Terminal Designations.................................................................................................... 5
Figure 10: Recommended Relay Protection Circuits ................................................................................ 7
Figure 11: Open Collector External Circ uit s ............................................................................................ 8
Figure 12: Sensor/Controller Connections .............................................................................................. 9
Figure 13: Switch Connections for Card Test Feature............................................................................... 9
Figure 14: Analog Signal Connections ..................................................................................................10
Figure 15: Power Connections.............................................................................................................11
Figure 16: Front Panel Display ............................................................................................................19
Figure 17: Portable Purge Calibrator ....................................................................................................20
Figure 18: Entering CAL Check Mode...................................................................................................20
Figure 19: Portable Purge Calibrator ....................................................................................................22
Figure 20: Entering CAL Mode ............................................................................................................22
Figure 21: AC Display during CAL Mode...............................................................................................23
Figure 22: CP Display during CAL Mode...............................................................................................23
Figure 23: CC Display during CAL Mode...............................................................................................24
Figure 24: F7 Display during CAL Mode................................................................................................24
Figure 25: Entering Setup and Setup Check Modes................................................................................26
Figure 26: Entering the Password ........................................................................................................27
Figure 27: Entering Inhibit Mode..........................................................................................................27
Figure 28: Energized/De-Energized Alarm Option...................................................................................28
Figure 29: A2 Latching/Non-Latching Alarm Option.................................................................................28
Figure 30: A2 Alarm Set Point Option...................................................................................................29
Figure 31: A1 Energized-De-Energized Alarm Option..............................................................................30
Figure 32: A1 Latching/Non-Latching Alarm Option.................................................................................30
Figure 33: A1 Set Point Option............................................................................................................31
Figure 34: Calibration Level ................................................................................................................31
Figure 35: Fault / Inhibit Option............................................................................................................32
Figure 36: Entering Card Test Options..................................................................................................32
Figure 37: Card Test Ramp Time.........................................................................................................33
Figure 38: Alarm Output during a Card Test...........................................................................................33
Figure 39: Password Enabled/Disabled Option.......................................................................................34
Figure 40: Entering A New Password ...................................................................................................35
Figure 41: Catalytic Sensor Diagram ....................................................................................................38
Figure 42: Universal Sensor Housing with Sensor and Splash-Guard ........................................................40
Figure 43: Splash-Guard Picture..........................................................................................................40
Figure 44: Dust Guard Picture.............................................................................................................41
Figure 45: Dust Guard Assemb ly Kit Picture ..........................................................................................41
Figure 46: Duct Mounting Plate, Assembly Drawing................................................................................42
Figure 47: Portable Purge Calibrator ....................................................................................................43
Figure 48: 3-Liter Chamber.................................................................................................................43
Figure 49: Outline and Terminal Connections 4802A...............................................................................53
Figure 50: Final Assembly, 4802A........................................................................................................54

Model 4802A
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List of Tables
Table 1: Terminal Designations for Sensor Wires ....................................................................................xi
Table 2: Terminal Designations for A2 Alarm Outputs .............................................................................. 6
Table 3: A2 Alarm Relay Contacts......................................................................................................... 6
Tab le 4: Terminal D es ig natio ns f o r A1 Alarm Outputs .............................................................................. 6
Table 5: A1 Alarm Relay Contacts......................................................................................................... 7
Table 6: Terminal Designations for Fault Outputs .................................................................................... 7
Tab le 7: Terminal D es ig natio ns f o r Un-accept and Calibration/Inhibit Mode................................................. 8
Table 8: Terminal Designations for Sensor Wires .................................................................................... 9
Table 9: Terminal Designations for Analog Output ..................................................................................10
Table 10: Rear Terminal Relay Contacts...............................................................................................14
Table 11: Fault Codes........................................................................................................................18
Table 12: Setup Display Options..........................................................................................................36
Table 13: GM Locations .....................................................................................................................37
Table 14: Recommended Maximum Cable Lengths between Module & Sensor...........................................48
Table 15: Maximum Allowable Cable Lengths between Analog Output Connections ....................................48

Model 4802A
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Warranty Statement
General Monitors warrants the Model 4802A to be free fro m defect s in workmanshi p o r
material under normal use and service within two (2) years f rom the date of shipment.
General Monitors will repair or replace without charge any such equipment f ound to be
def ective during the warranty period. Full determination of the nature of, and res ponsibi l it y
f or, defective or damaged equipment will be made by General Monitors’ personnel.
Def ective or damaged equipment must be shipped prepaid to the General Monitors’ plant or
the representative from which the shipment was made. In all cases, this warranty i s limit ed
to the cost of the equipment supplied by General Monitors. The custom er will assume al l
liability for the misuse of this equipment by its employees or other personnel.
All warranties are contingent upon proper use in the application for which the produc t was
intended and do not cover products which have been modified or repaired without General
Monitors’ approval or which have been subjected to neglect, accident, improper installation
or application, or on which the original identification marks have been removed or altered.
Except for the express warranty stated above, General Monitors disclaims all warranties with
regard to the products sold, including all implied warranties of merchantabil i ty and f i tness
and the express warranties stated herein are in lieu of all obligations or liabilities on the p art
of General Monitors for damages including, but not limited t o, cons equential damages
arising out of/or in connection with the use or performance of the product.
Special Warnings
Combustible & flammable gases and vapors are very dangerous. Extreme caution should be
used when combustible & flammable gases and vapors are present.
All Zero Two Series Modules contain 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.
Only catalytic bead sensors designed by General Monitors will work with the Model 4802A.
Any attempt to use a sensor that has not been designed by General Monitors will void the
warranty.
Installation and maintenance must be carried out by suitably skilled and competent
personnel only.
Full backward compatibility can be specified at the time of order. If t his c onf i gurat ion is
specified, the rear terminal output designations will be identical to the previous generation of
Zero Two Series Modules.
This generation of product can be distinguished from the previous generation by the l ack of
a door on the front panel. Adjustments are not necessary on the current generation of t his
product.

Model 4802A
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System Integrity Verification
General Monitors’ missionis to benefit society by providing solutions through industry-
leading safety products, services and systems that save lives and protect capital res ources
f rom the dangers of hazardous flames, gases and vapors.
The saf ety products you have purchased should be handled caref ully and installed,
calibrated, and maintained in accordance with the respective product ins truct ion manual.
Remember, these products are for your safety.
To ensure operation at optimum performance, General Monitors recommends t hat cert ai n
maintenance items are performed.
Commissioning Safety Systems
Bef ore power up, verify wiring, terminal connections and stability of mounting for all int egral
saf ety equipment including, but not limited to:
•Power supplies
•Control modules
•Field detection devices
•Signaling / output devices
•Accessories connected to field and signaling devices
Af ter the initial application of power (and any factory specified warm-up period) to the safety
system, verif y that all signal outputs, to and f rom devices and modules, are within the
manuf acturers’ specifications. Initial calibration / calibration checking / testing should be
perf ormed per the manufacturers’ recommendations and instructions.
Proper system operation should be verif ied by perf orming a f ull, f unctional test of all
component devices of the safety system, ensuring that the proper levels of alarming occur.
Fault/Malfunction circuit operation should be verified.
Periodic Testing/Calibration of Field Devices
Periodic testing/calibrating should be performed per the manufacturers’ recommendations
and instructions. Testing/Calibrating procedures should include, but not be limited to:
•Verif y zero reading
•Apply a known concentration of gas, or a simulated test device provi ded b y t he
manuf acturer
•Verif y integrity of all optical surfaces and devices.

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When testing produces results outside of the manufacturers’ specifications, re-calibration or
repair/replacement of the suspect device(s) should be performed as necessary. Calibrat ion
intervals should be independently established through a documented procedure, including a
calibration log maintained by plant personnel, or third party testing services.
Specific Conditions of Use
•The Model 4802A Hydrocarbon Point Gas Detector was not accessed to EN 50271
Clause 4.8. For the Model 4802A the current firmware version is S.
•The Model 4802A Hydrocarbon Point Gas Detector complies with combustible gas
detection performance according to EN 60079-29-1: 2016 for detection of 0-100% LFL
methane only.
•Guidance for installation of fixed gas detection systems are set out in EN 60079-29-2
which has not been covered in the scope of this assessment.
•Guidance for functional safety of fixed gas detection systems are set out in EN 60079-
29-3 which has not been covered in the scope of this assessment.

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1.0 Quick-Start Guide
1.1 Control Module Installation
A rack or panel mounted chassis will be required when installing any Zero Two Series Modul e.
These chassis’ should be mounted in non-hazardous, weather-protected locations and s houl d
be subjected to minimal shock and vibrations. The rack and panel mounted chassis are
available in 4, 8, and 16 channel sizes. Multiple 16-channel chassis may be connected to eac h
other to form larger systems.
In installations where two or more module types are to be mixed in the same chas sis, ens ure
that the individual coding strips match the channel application. The coding strips are pre-
conf igured at the factory and the male portion is already on each module.
The f emale portion, if un-mounted, must be fastened into position on the mounting stri p of t he
desired chassis channel so as to mate with its counterpart on the module (Figure 1).
Figure 1: Control Module Coding Strip
NOTE: Zero Two Series Modules require air circulation to avoid excess iv e heat b uild-up. If
chassis are stacked vertically within an enclosure, f orced air circulation may be
required. The control modules are, to a great extent, immune to electromagnetic
interf erence (EMI). However, they should not be mounted in close p roximit y t o radio
transmitters or similar equipment.

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1.2 Rear Terminal Connections
All wire connections to the Model 4802A are made to the terminal block located at t he rear o f
the chassis. The terminal block accepts 16 AWG to 20 AWG, stranded or solid core wire.
14 AWG wire may be used if it is properly stripped according to Figure 2.
Figure 2: Wire Strip Length
CAUTION: Contact with PC Board components should be avoided in order to prevent
damage by static electricity.
To connect wires to the terminal block on the Model 4802A, loosen the desired screw, insert
the stripped end of the wire and tighten.
For the rear terminal designations refer to Figure 3 below:
Figure 3: Rear Terminal Designations
(BLACK)
(RED)
(WHITE)
SENSOR
(BLACK)
(RED)
(WHITE)
SENSOR

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1.3 Sensor Connections
The terminal designations for the sensor wires are:
Label
Term
Description
BLK
26d,z
Black Sensor Wire
RED
28d,z
Red Sensor Wire
WHT
30d,z
White Sensor Wire
Table 1: Terminal Designations for Sensor Wires
NOTE: Only 1 sensor may be connected to a Model 4802A.
Figure 4 illustrates the Sensor/Controller connections.
Figure 4: Sensor/Controller Connections
1.4 Applying Power
Zero Two Series Modules do not have an ON/OFF power switch. Each module in the Zero Two
Series operates from 24Vdc. Current requirements will vary according to the number and ty pe
of modules in the system, as well as the number and type of field devices.
NOTE: If the application of power does not turn ON the unit, check fuse, F1 on the control
board. If the unit displays an F4 condition upon power-up first try to clear this conditi on
by calibrating the sensor. If this condition persists, replace the sensor.

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Figure 5 indicates where the power connections for the chassis are made.
Figure 5: Rear Power Connections
The instrument is now ready to operate. Please consult the manual for more information on the
instrument’s many features.

Model 4802A
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2.0 Introduction
This chapter provides a brief description of the Model 4802A, its features & benefits, and a lis t
of some of its applications. More detailed information on the features and benef i ts lis ted i n
Section 2.2 will be presented in later chapters.
WARNING: Installation and Maintenance must be carried out by suitably skilled and
competent personnel only.
2.1 General Description
The General Monitors’ Model 4802A (Figure 6) is a single channel combustible gas detec tion
control module designed for use in Zero Two Series Gas and Flame Detection Sy stem s. Thi s
module connects to the wires from a f ield mounted General Monitors’ catalytic bead sensor and
monitors the presence of combustible gases and vapors. The 4802A is electrically and
physically compatible with the other gas detection, flame detection, and system modules in t he
Zero Two Series. It is distinguished from the other modules by its blue border and “4802A" in
the upper right corner of the front panel. The 4802A is designed f or use in no n-hazardous
environments.
Figure 6: Model 4802A

Model 4802A
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2.2 Features & Benefits
Automatic Calibration
The unit’s display indicates simple automated calibration prompts to the operator with no
calibration adjustments.
Calibration Check Mode
Verif ies the integrity of the sensor by allowing the operator to apply a t es t gas and v iew t he
response on the display.
Calibration Level
The user specifies the gas concentration to be used for calibration.
Microprocessor Based Electronics
Monitors fault conditions; sensor inputs and provides outputs in the form of display codes,
analog signal, relay contact and open collector activation.
Setup Mode
Allows the user to set parameters such as alarm output options, test options, etc. These
parameters are viewed on the display during the Setup Mode.
Password Option
Prevents unauthorized alteration of the setup parameters (can be disabled).
Setup Check Mode
Allows the user to view the setup parameters, which have been set by the f actory and/or
operator.
LED Test
Tests the integrity of each LED and each segment of the digital display on the front panel.
Card Test
Tests the f unctionality of the card through the microprocessor, ramping the signal from 0 to full-
scale.
Live Insertion/Removal
Allows the user to insert or remove a module while power is applied to the system, without
damage to any of the components in the system.

Model 4802A
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2.3 Applications
The 4802A is a Combustible Gas Control Module designed for Zero Two Series Applic ations.
Below is a partial list of applications:
•Ref ineries
•Drilling platforms and rigs
•Gas and oil production
platf orms
•Gas collection facilities
•Oil well logging operations
•LPG/LNG processing and
storage
•Gas Turbines
•Solvent Vapors
•Hydrogen Storage
•Wastewater treatment
plants
•Chemical plants

Model 4802A
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3.0 Installation
This chapter discusses what to do when a Model 4802A is received, the terminal connections &
designations, sensor location considerations, and what to be aware of when applying power.
3.1 Upon Receipt of Equipment
All equipment shipped by General Monitors is packaged in shock absorbing containers, which
provide considerable protection against physical damage. The content s s hould b e caref ully
removed and checked against the packing slip. If any damage has occurred or if there is any
discrepancy in the order, notif y General Monitors as soon as possible. All subsequent
correspondence with General Monitors must specify the equipment part and serial numbers.
Each Model 4802A is completely checked at the factory; however, a c omplete c heckout is
necessary upon initial installation and start-up to ensure system integrity.
3.2 Control Module Installation
A rack or panel mounted chassis will be required when installing any Zero Two Series Module.
These chassis should be mounted in non-hazardous, weather-protected locations and should
be subjected to minimal shock and vibrations. The rack and panel mounted chassis are
available in 4, 8, and 16 channel sizes. Mult iple 16-channel chassis may be connected to eac h
other to form larger systems.
In installations where two or more module types are to be mixed in the same chas sis, ens ure
that the individual coding strips match the channel application. The coding strips are pre-
conf igured at the factory and the male portion is already on each module.
The f emale portion, if un-mounted, must be fastened into position on the mounting strip of t he
desired chassis channel so as to mate with its counterpart on the module (Figure 7).
Figure 7: Control Module Coding Strip

Model 4802A
5
NOTE: Zero Two Series Modules require air circulation to avoid excess iv e heat b uil d-up. If
chassis are stacked vertically within an enclosure, forced air circulation may be
required. The control modules are, to a great extent, immune to electromagnetic
interf erence (EMI). However, they should not be mounted in close p roximit y t o radi o
transmitters or similar equipment.
3.3 Rear Terminal Connections
All wire connections to the 4802A are made to the terminal block lo cated at t he rear o f the
chassis. The terminal block accepts 16 AWG to 20 AWG, stranded or solid core wire.
14 AWG wire may be used if it is properly stripped according to Figure 8.
Figure 8: Wire Strip Length
CAUTION: Contact with PC Board components should be avoided in order to prevent damage
by static electricity.
To connect wires to the terminal block on the 4802A, loosen the desired screw, insert the
stripped end of the wire, and tighten.
For the rear terminal designations refer to Figure 9 below:
Figure 9: Rear Terminal Designations
(BLACK)
(RED)
(WHITE)
SENSOR
(BLACK)
(RED)
(WHITE)
SENSOR

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3.3.1 A2 Alarm
The terminal designations for the A2 alarm outputs are:
LABEL
TERM
DESCRIPTION
A2-C1
2d
Relay Common (1 & 2)
A2-1
4d
Relay Contact
A2-2
6d
Relay Contact
A2-3
8d
Relay Contact
A2-4
10d
Relay Contact
A2-C2
12d
Relay Common (3 & 4)
A2-OC
14d
Open Collector (OC)
LA2
24z
OC Logic for A2 LED
Table 2: Terminal Designations for A2 Alarm Outputs
The A2 alarm outputs are DPDT relays, 1 open collector output (A2-OC) that follows t he logi c
of the relays and 1 open collector output (LA2) that follows the blinking pattern of the front
panel LED. The A2-C1 designation is common for A2-1 & A2-2. The A2-C2 designation is
common for A2-3 & A2-4. The normally open (NO) and normally closed (NC) contacts depend
on a user selectable option (Chapter 5). The table below refers to the proper open and cl osed
A2 alarm relay contacts while the unit is on power:
User Selected
Relay State
Normally
Open
Normally
Closed
Normally
Energized
A2-C1 & A2-1,
A2-C2 & A2-4
A2-C1 & A2-2,
A2-C2 & A2-3
Normally
De-Energized
A2-C1 & A2-2,
A2-C2 & A2-3
A2-C1 & A2-1,
A2-C2 & A2-4
Table 3: A2 Alarm Relay Contacts
3.3.2 A1 Alarm
The terminal designations for the A1 alarm outputs are:
Label
Term
Description
A1-C1
2z
Relay Common (1 & 2)
A1-1
4z
Relay Contact
A1-2
6z
Relay Contact
A1-3
8z
Relay Contact
A1-4
10z
Relay Contact
A1-C2
12z
Relay Common (3 & 4)
A1-OC
14z
Open Collector (OC)
LA1
24d
OC Logic for A1 LED
Table 4: Terminal Designations for A1 Alarm Outputs
The A1 Alarm outputs are DPDT relays, 1 open collector output (A1-OC) that follows the l o gic
of the relays and 1 open collector output (LA1) that follows the blinking pattern of the front
panel LED. The A1-C1 designation is common f or A1-1 & A1-2. The A1-C2 designation is
common for A1-3 & A1-4. The normally open (NO) and normally closed (NC) contacts d epend

Model 4802A
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on a user selectable option (Section 5.0).The table below ref ers to the proper open and clos ed
A1 alarm relay contacts while the unit is on power:
User Selected
Relay State
Normally
Open
Normally
Closed
Normally
Energized
A1-C1 & A1-1,
A1-C2 & A1-4
A1-C1 & A1-2,
A1-C2 & A1-3
Normally
De-Energized
A1-C1 & A1-2,
A1-C2 & A1-3
A1-C1 & A1-1,
A1-C2 & A1-4
Table 5: A1 Alarm Relay Contacts
3.3.3 Fault Alarm
The terminal designations for the Fault outputs are:
Label
Term
Description
F-C
16z
Relay Common
F-1
18z
Relay Contact (NO)
F-2
20z
Relay Contact (NC)
F-OC
22z
Open Collector (OC)
FUA
32d
Open Collector (OC)
Table 6: Terminal Designations for Fault Outputs
The Fault outputs are SPDT relays, 1 open collector output (F-OC) that follows the logic of the
relays and 1 open collector output (FUA) dedicated to new fault indications.
NOTE: If the backward compatible configuration is ordered, the FUA will not b e present (pi n
32d will be f or +B).
The f ault outputs are always normally energized when power is applied to the module.
The contact ratings for the A2 & A1 alarm and fault relays are 4A @ 250 Vac, 3A @ 30 Vdc,
resistive, maximum.
Inductive loads (bells, buzzers, relays, etc.) on dry relay cont act s must b e cl am ped down.
Unclamped inductive loads can generate voltage spikes in excess of 1000 volts. Spikes of t his
magnitude may cause false alarms and contact damage. Figure 27 shows recommended relay
protection circuits for AC and DC loads, respectively.
Figure 10: Recommended Relay Protection Circuits

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3.3.4 Other Open Collector Outputs
The terminal desig natio n f or the Un-accept and the Discrete Calibration / Inhibit Mode
outputs are:
Label
Term
Description
UA-OC
18d
Un-accept Output
CAL/INH
32z
CAL-Inhibit Mode Output
Table 7: Terminal Designations for Un-accept and Calibration/Inhibit Mode
NOTE: If the backward compatible configuration is ordered, the CAL/INH will no t be pres ent
(pin 32z will be for 0v).
The electrical rating for all open collector outputs is 100mA @ 35Vdc.
Figure 11 illustrates some typical open collector external circuits.
Figure 11: Open Collector External Circuits