Det-Tronics 95-8311-02 User manual

Instructions 95-8311-02
UV/IR Flame Detection System
R7494 Controller/C7052J Detector
Detector Electronics Corporation
6901 West 110th Street •Minneapolis, Minnesota 55438 USA
Tel: [phone] or 800.765.3473 •Fax: [phone]-8311-02

APPLICATION........................................................................1
FEATURES.............................................................................1
SYSTEM DESCRIPTION .......................................................2
Detector...........................................................................2
oiFeature .......................................................................2
Detector Enclosure..........................................................3
Controller.........................................................................3
Front Panel......................................................................3
Programming Switches....................................................4
Controller Outputs ...........................................................5
Field Wiring Connector....................................................7
SPECIFICATIONS..................................................................7
OPTIONS................................................................................9
RESPONSE CHARACTERISTICS.........................................9
APPLICATION GUIDELINES .................................................9
INSTALLATION ....................................................................11
Detector Positioning ......................................................11
Wiring Requirements.....................................................11
Detector Mounting and Wiring Procedure .....................12
Controller Installation and Wiring...................................17
Electrical Connections...................................................17
Programming the Controller ..........................................19
TYPICAL SYSTEM APPLICATION ......................................23
STARTUP PROCEDURE.....................................................24
INITIAL AND PERIODIC CHECKOUT PROCEDURE..........24
Bus Test Mode ..............................................................26
Star Programming Checkout Procedure........................26
MAINTENANCE....................................................................27
Sensor Module Replacement Procedure.......................27
TROUBLESHOOTING..........................................................28
Manual oiTest..............................................................28
Count Test Mode...........................................................28
DEVICE REPAIR AND RETURN .........................................29
ENGINEERING SPECIFICATIONS......................................30
ORDERING INFORMATION ................................................31
Accessories ...................................................................31
Recommended Spare Parts ..........................................31
APPLICATION ASSISTANCE ..............................................31
List of Illustrations
Figure 1 Detector Sensitivity Range ..................................2
Figure 2 oiFunction within the Detector...........................3
Figure 3 Front Panel of R7494 ..........................................3
Figure 4 Open Controller Outputs with Transient
Suppression Device Connected ..........................6
Figure 5 Intercontroller Communications...........................6
Figure 6 Cone of Vision .....................................................7
Figure 7 Detector Dimensions in Inches (mm) ..................8
Figure 8 Dimensions of R7494 in Inches (mm) .................8
Figure 9 Blackbody Spectral Emittance...........................10
Figure 10 Front View of the C7052 Detector .....................12
Figure 11 C7052J Detector Part Identification...................13
Figure 12 Mounting Base Dimensions...............................13
Figure 13 Q9001G Swivel Mounting Bracket Dimensions.13
Figure 14 Detector Terminal Block ....................................15
Figure 15 Detector and Power Connections......................15
Figure 16 Cover Locking Assembly (Optional) ..................16
Figure 17 Jumper Plug ......................................................16
Figure 18 IR Module with Four-Wire Connector ................16
Figure 19 Q4004 Mounting Cage Dimensions in
Inches (mm).......................................................17
Figure 20 Terminal Configuration ......................................18
Figure 21 Rocker Switch Setting .......................................19
Figure 22 Graphic Representation of STAR Logic
(Typical Settings Shown)...................................20
Figure 23 Multiplication Factors.........................................22
Figure 24 System Layout Chart.........................................23
Figure 25 Block Diagram of a Typical R7494 System
Application.........................................................24
Figure 26 Data Bus Wiring.................................................25
List of Tables
Table 1 Relationship of Zone and Status Codes..............5
Table 2 C7052 Typical Response Distance .....................9
Table 3 Radiation Absorbing Gases and Vapors ...........10
Table 4 Relationship of ZONE and DETECTOR
Display to the Status Outputs............................18
Table 5 Relationship of SYSTEM STATUS Display to
Status Outputs...................................................19
Table of Contents

APPLICATION
The R7494/C7052J UV/IR Flame Detection System is
designed to provide continuous and automated fire
protection in applications where the use of ultraviolet
(UV) or infrared (IR) detectors alone can result in
unwanted (false) alarms. The R7494/C7052J system
features a flame detector that uses both a UV and a
single frequency IR sensing device mounted side-by-
side on a junction box assembly.
When used alone, a UV detector can respond to
sources of ultraviolet radiation besides fire, such as
lightning, x-rays or arc welding. A UV detector does
not respond to the radiation emitted by flickering hot
objects. Likewise, an IR detector can respond to
infrared radiation sources besides hydrocarbon fires,
such as flickering hot objects. An IR detector does
not respond to radiation from lightning, x-rays or arc
welding. Since both UV and IR sensors respond to
hydrocarbon fires but have virtually no false alarm
sources in common, the R7494/C7052J UV/IR system
provides reliable flame detection while being virtually
immune to false alarms.
The junction box contains a power supply and signal
processing circuitry for the sensors. A fire signal is
generated in the detector junction box and sent to the
controller only when a fire is simultaneously detected
by both the UV and IR sensors. Since the two detect-
ing elements independently monitor different portions
of the radiation spectrum and have virtually no
sources of output actuation in common besides fire, a
high degree of false alarm immunity is achieved. The
controller continuously monitors up to eight UV/IR
detectors and generates a fire alarm in response to a
fire signal from the detectors.
Typical applications include:
—Transport loading terminals
—Offshore drilling and production platforms
—Tank farms
—Refineries
—Butane and propane loading and storage
—Pipeline compressor stations
—Turbine enclosures
—Aircraft Hangars
—Paint Spray Booths
—Chemical and petrochemical production
FEATURES
• Controller continuously monitors up to eight detec-
tors.
• Ignores false alarm sources such as arc welding, x-
rays, gamma radiation and radiation from flickering
hot objects.
• Fast response - typically 1 to 5 seconds for an
intense hydrocarbon fire.
• Each detector can independently register an alarm.
INSTRUCTIONS
UV/IR Flame Detection System
R7494 Controller
C7052J Detector
©Detector Electronics Corporation 1994 5/94 95-8311-02
DET-TRONICS®
*oiis Detector Electronics' Trademark for its patented Optical
Integrity Systems, U.S. Patent 3,952,196, United Kingdom Patent
1,534,969, Canada Patent 1,059,598.

• Front panel LEDs indicate fire response and general
system status.
• Microprocessor control provides continuous diag-
nostics and automatic fault identification.
• Automatic Optical Integrity (oi) for both UV and IR
sensors.
• Explosion-proof (flame-proof) detector housing
• FM approved, CSA and BASEEFA/CENELEC certi-
fied.
• Count test mode allows monitoring of actual detec-
tor output.
• Bus test mode allows verification of data bus wiring.
• Voting circuitry for improved false alarm rejection.
• Up to eight controllers can be wired to provide up to
64 voting detector zones.
SYSTEM DESCRIPTION
DETECTOR
The C7052J UV/IR Flame Detector is an explosion-
proof device that consists of a UV sensor and an IR
sensor mounted side-by-side on a junction box. This
mounting arrangement allows both sensors to monitor
the same hazardous location with a 80 degree cone
of vision. Up to eight C7052J Detectors can be con-
nected to one R7494 Controller.
The UV sensor responds to high energy radiation with
wavelengths from 0.185 to 0.245 microns (1850 to
2450 angstroms). See Figure 1. It detects radiation
from sources such as fire, arc welding, lightning, x-
rays and gamma rays. However, it is not sensitive to
radiation from the sun or radiation from flickering hot
objects (blackbodies).
The IR sensor is sensitive to IR radiation over the
range of 4.2 to 4.7 microns. See Figure 1. It is not
sensitive to radiation from the sun, lightning, x-rays,
gamma rays, or arc welding. However, it will respond
to fire and flickering blackbody (heat) radiation
sources. IR radiation that is generated by a hydrocar-
bon flame which reaches the detector in pulsations or
“flicker.” These pulsations are present in all flames
and are created by turbulent mixing of fuel with air.
For this reason, electronic circuitry in the detector
monitors the output of the IR sensing element for the
appropriate amplitude and a flicker frequency
between 1 and 16 cycles per second. If both the
radiation and flicker requirements are met, a fire sig-
nal is generated. This dual criteria for the IR detector
results in increased reliability. However, since the IR
detector responds only to hydrocarbon fires, the
UV/IR detector cannot respond to non-hydrocarbon
fires such as burning hydrogen, ammonia or metal.
The detector junction box contains a +290 vdc power
supply for the UV sensor as well as circuitry to pro-
cess signals from both sensors. When both sensors
detect a fire, the IR sensor activates the circuitry in
the junction box to allow the signal from the UV sen-
sor to be sent to the controller. By using both a UV
and an IR sensor, the C7052J is able to discriminate
virtually all false alarm sources from a true hydrocar-
bon fire.
oiFEATURE
Both sensors are equipped with the automatic oitest
feature. This patented system assures proper opera-
tion of the detector by checking the cleanliness of the
optical surfaces, sensitivity of the sensors and proper
functioning of the electronic components of the detec-
tor once every minute. If a problem should occur, it is
quickly detected. The oi test is accomplished with-
out the use of an external UV or IR source. To mini-
mize the possibility of nuisance fault signals, the
detector must fail the automatic oitest three consec-
utive times for an oifault signal to be generated
The oitest is initiated by a signal from the controller
which causes actuation of the oitest lamps. A cali-
brated low level test beam is generated by the oitest
lamps, as shown in Figure 2. Although the test lamps
are mounted in the same enclosure with the sensor,
an optical shield prevents the test beam from reach-
ing the sensor directly. The test beam travels out
through the viewing window, where it encounters the
2
Figure 1—Detector Sensitivity Range
5.04.03.02.01.51.00.90.80.70.60.50.40.30.20.1
ATMOSPHERIC
TRANSMISSION
WAVELENGTH (MICRONS)
SOLAR RADIATION REACHING THE EARTH
VISIBLE INFRARED
ULTRAVIOLET SENSOR RESPONSE
ULTRAVIOLET
100
75
50
25
0
A1516
INFRARED SENSOR RESPONSE

reflective oiring and is directed back through the
window to the sensor. Electronic circuitry in the
detector then evaluates the return signal from the sen-
sor and generates the appropriate output response.
Since the test beam must pass through the same por-
tion of the viewing window as radiation produced by a
fire, this test of the ability of the detector to “see” a
flame has a high degree of reliability.
DETECTOR ENCLOSURE
The C7052J features an explosion-proof, dust-tight
and water-tight (NEMA 4/IP66) housing that is
designed for installation in hazardous locations in
both indoor and outdoor environments. The enclo-
sure is FM approved, CSA certified and BASEEFA/
CENELEC approved.
CONTROLLER
The R7494 is designed for use with 24 volt dc power
supplies, but will operate from any direct current sup-
ply between 18 and 32 volts. The unit will tolerate
transients such as those that can occur when fully
discharged batteries are placed on charge. When
power is present at the R7494 Controller, it is indicat-
ed by a continuously energized green LED. All other
lights and displays on the R7494 front panel are nor-
mally off, but may be periodically checked for opera-
tion by pressing the LAMP TEST button located
directly opposite the POWER light as illustrated in
Figure 3. It is not necessary for the controller to be in
the TEST mode when this check is performed.
With power applied, the R7494 Controller continuous-
ly cycles through the Automatic oitest (see the “oi
Feature” section), checking each detector and its
wiring. At the same time, it monitors the system for
any status changes, such as a fault, a “fire” signal
from one of the detector zones, or a change in the
setting of the keylock switch. If a status change
occurs, the controller will respond accordingly by
indicating the change on the front panel and generat-
ing the appropriate output.
FRONT PANEL
The front panel of the R7494 provides switches for
selecting mode of operation and initiating test func-
tions. It also provides LEDs and digital displays for
indicating system status information. Figure 3 illus-
trates the front panel of the controller.
3 95-8311
UV DETECTOR
IR DETECTOR
UV TEST LAMP
OPTICAL SHIELD
VIEWING WINDOWSNAP-IN oiRING
IR TEST LAMP (2)
IR SENSING ELEMENT
SNAP-IN oiRING
OPTICAL FILTER
VIEWING WINDOW
UV SENSOR
B1048
Figure 2—oiFunction within the Detector
A1711
KEYLOCK SWITCH
AMBER LED
TEST/ACCEPT
RED LEDS
LAMP TEST
DETECTOR SELECTION
AMBER LED
GREEN LED
Figure 3—Front Panel of R7494

1. A ZONE OUTPUT LED is provided for each
detector to indicate that a fire has been detected.
The LEDs blink while the zone output is active and
latch on when the fire is no longer detected and the
output turns off.
2. The FIRE LOGIC LEDs signal actuation of the cor-
responding Logic outputs.
3. The DETECTOR - ZONE digital display indicates
the detector zone number that first responded to
a fire, detector(s) indicating a fault, detector zone
selected manually in the keylock switch Test
mode, or the counts per second reading from the
detector zone in the Count Test mode.
4. The SYSTEM STATUS display uses a numerical
code to identify system status (see Table 1).
5. Illumination of the FAULT LED indicates a system
malfunction (or that the controller is in the Reset
or Test mode).
6. The INHIBIT LED is energized in the Test or Reset
mode to show that the outputs of the controller
are inhibited.
7. The POWER LED is illuminated when power is
applied to the system.
8. The SELECT button is pressed to choose a detec-
tor for test.
9. In the Test mode the TEST/ACCEPT button initi-
ates a manual oitest for the selected detector.
In the Normal mode, the TEST/ACCEPT button is
used to disable the alarm output when a fire
occurs without affecting the Zone or Fire Logic
outputs.
10. The LAMP TEST button illuminates all LEDs and
all segments of the displays. In the Reset mode,
it initiates a complete microprocessor reset.
11. The keylock switch selects NORMAL, RESET or
TEST mode.
Normal Mode
In the Normal operating mode, the R7494 Controller
monitors the outputs of all detectors connected to it
and compares the detector output signals to field
adjusted settings (refer to the “STAR Logic
Programming” procedure in the “Programming the
Controller” section) to determine whether a fire condi-
tion exists. Diagnostic circuitry continuously checks
the system for wiring continuity as well as faults that
could prevent proper response to a fire through the
Automatic oifeature. The Zone, Fire Logic and Fire
Alarm outputs are de-energized. The Fault output is
energized, as long as no system malfunctions are
detected. None of the LEDs except the POWER LED
are illuminated and the digital displays are blank.
Reset Mode
Any existing system status indications and the con-
troller outputs are returned to normal operating condi-
tion (after the radiation source is removed or the fault
is corrected) in one of the following ways:
1. Place the keylock switch in the RESET position,
then return it to NORMAL.
2. Close the optional remote reset switch connected
to controller terminal 44 and circuit ground (termi-
nal 2).
Test Mode
In the Normal mode, the Automatic oifeature continu-
ously checks the detectors for proper operation.
Additional manual oitesting capabilities are provided
by using the controller Test mode. Among the possi-
ble tests are:
1. A Manual oitest, which individually tests the
selected detector and its electronic circuitry.
2. A Count Test mode, which displays the output fre-
quency of an individual detector using the
DETECTOR and ZONE displays.
3. A Bus Test mode, which tests the data bus wiring
and indicates results on the front panel of the
controller when intercontroller voting is used.
These test features enable the user to more easily
pinpoint a system malfunction. Refer to the
“Troubleshooting” section.
PROGRAMMING SWITCHES
Rocker switches that are located on the side of the
controller are used for selecting various options avail-
able with the R7494. These programming options are
listed below and must be set prior to system opera-
tion. Refer to the “Programming the Controller” sec-
tion for detailed instructions.
1. Number of detectors connected to the controller
(up to eight)
2. Gate Length, Consecutive Gate Selection, Count
Selection (system sensitivity and time delay).
3. Fire Logic (voting arrangement)
4. Latching/non-latching outputs.
5. Intercontroller voting.
4

CONTROLLER OUTPUTS
The R7494 has Open Collector Transistor Outputs
rated at 100 ma maximum (not to exceed 60 vdc) for
external indication of system status. These outputs
along with a brief description are listed below. An
internal 100 kilohm resistor is connected from the out-
put to circuit ground (terminal 2).
NOTE
External equipment that may generate transients
when switching (such as relays) should have a
transient suppression device connected across
the coil at the time of installation to safeguard the
output transistors against possible damage (see
Figure 4).
Zone Outputs - Each of the eight detectors has
its own independent Zone output that is ener-
gized upon detection of a fire that exceeds the
selected duration (gate length and consecutive
gates) and the selected intensity (count selec-
tion). An LED on the front panel illuminates to
show the zone output is active.
5 95-8311
System
Zone Status Condition
0 0 Keylock switch is in reset position, or the external inhibit being used.
(Outputs inhibited, except Status Outputs.)
1 to 8 1 Keylock switch is in TEST position. (Outputs inhibited, except Status
Outputs.)
1 to 8 2 oi
fault - either the
oi
ring and/or the window of the zone indicated
in the upper right display is dirty, or the detector module has lost
sensitivity, or there is a wiring fault between the detector and the
controller of power supply, or the detector module is missing, or the
electronics module in the detector junction box is defective, or power
to detector is below the 18 vdc minimum.
Blank 3 One or more detectors are responding to a UV/IR source that has
not yet met consecutive gate time or is not large enough to reach the
fire threshold programmed into the controller. FAULT LED is not
turned on. Affected ZONE OUTPUT LED blinks slowly (1 per sec-
ond). This status does not latch on. The normally energized Fault
output remains energized.
Blank 4 Low +5 vdc caused by failure in the regulating network in the con-
troller.
Blank 5 High +5 vdc caused by failure in the regulating network in the con-
troller.
6 Fire Output Signal - Blinking ZONE OUPUT LED indicates fire loca-
tion. Steady ZONE OUTPUT LED indicates that the detectors in
that zone have responded to a UV/IR signal, but are no longer
responding. Zone Display the first zone that registered the alarm
condition.
Blank 7 Data Bus fault
1 to 8 8 Controller has been placed in "count" mode (see "Checkout" sec-
tion). Pushing and releasing both SELECT and TEST/ACCEPt but-
tons at the same time while the keylock switches in the TEST posi-
tion changes the lower display to a numeral "8" - the count rate of
each zone.
Blank Blank FAULT LED is on, indicating a problem in the R7494 microprocessor
circuitry. Place keylock switch in RESET, push and release LAMP
TEST pushbutton. If operation does not return to normal, replace
the entire R7494 BE SURE the new R7494 is programmed the same
as the R7494 being replaced.
Table 1—Relationship of Zone and Status Codes

Fire Logic Output(s) - If the fire signals from the
responding detectors satisfy the selected voting
requirements, actuation of the Fire Logic output(s) will
also occur. This voting logic feature allows detectors
to be “grouped” and generate a Fire Logic output if
the minimum number of detectors respond to a fire.
The detectors can be grouped in one of two ways:
1. Separate Voting
The eight fire zones (detectors) are divided into two
groups: Fire Logic A (zones 1 to 4) and Fire Logic B
(zones 5 to 8). The controller can then be pro-
grammed to produce a logic output when either one
or two of the four zones in a group detects a fire.
2. Common Voting
All eight fire zones (detectors) vote together in one
group. When the minimum number of detectors sig-
naling a fire condition meets the field selectable vot-
ing requirements (1 to 7 detectors) the Fire Logic B
output is energized.
The common voting feature can also be used in multi-
ple controller systems. Up to eight controllers can be
connected by way of the data bus to allow inter-con-
troller voting of up to 64 detectors in a group. The
controllers are connected in series so alarm informa-
tion from the first controller (master) is sent to the sec-
ond (slave) and then down the line to the following
slave controllers (see Figure 5). Note that the infor-
mation transfer moves in one direction only. Alarm
information from the end controller does not return to
the master controller. Each controller in the series
can be programmed to energize its Logic B output
when the minimum number of detectors (one to
seven) connected to it and/or “upstream” controllers
detect a fire. Fault output (terminal 46) and Alarm
output (terminal 43) information is not transferred over
the data bus and must be monitored separately when
inter-controller voting is utilized.
A data bus test is automatically executed by the con-
troller fault detection circuitry to verify correct connec-
tions of the data bus lines and proper functioning of
the inter-controller communication circuitry.
This voting logic feature allows different combinations
of detectors to fulfill the logic requirements, and pro-
vides the best balance between dependable fire
detection and freedom from false alarms.
Alarm Output - If a UV/IR detector sends a signal that
exceeds the gate length, consecutive gates and
count selection requirements, a solid state alarm out-
put is immediately energized. This alarm output is
typically used to control an external device for visually
or audibly signaling a fire condition.
Ext Reset/Inhibit - Connecting a switch between termi-
nal 44 and circuit ground (terminal 2) allows the con-
troller to be reset or inhibited from a remote location.
Outputs Inhibited - Connecting an indicating device
to the solid state output (terminal 45) provides a sig-
nal when the outputs are inhibited due to the con-
troller keylock switch position or by an External
Reset/Inhibit switch input.
Fault Output - The R7494/C7052J system provides
the Automatic oifeature for continuously checking
the cleanliness of the viewing window and the sensi-
tivity of the sensor. In addition, automatic diagnostic
circuitry in the controller monitors the system for
wiring continuity faults as well as other malfunctions
that could prevent the system from responding in the
event of a fire. If a fault is detected:
1. A normally energized solid state Fault output is
de-energized. This provides a means of control
for an external fault annunciation device (if used).
2. A FAULT LED on the front panel of the controller
is illuminated to provide a visual indication that a
system fault has occurred.
6
MASTER
IN OUT
SLAVE CONTROLLERS
IN OUT IN OUT IN OUT IN OUT IN OUT IN OUT IN OUT
NUMBER 1 NUMBER 2 NUMBER 3 NUMBER 4 NUMBER 5 NUMBER 6 NUMBER 7 NUMBER 8
A1460
Figure 5—Intercontroller Communications
Figure 4—Open Controller Outputs with Transient
Suppression Device Connected
100K
CONTROLLER
OPEN COLLECTOR OUTPUT
1N4004
TYPICAL
+60 VDC MAXIMUM
A1459

3. The STATUS display uses numerical code to indi-
cate the nature of the fault. (see Table 1).
4. The ZONE display uses numerical code to indi-
cate the detector/zone affected (if applicable).
External Accept - Connecting a switch between termi-
nal 47 and circuit ground (terminal 2) allows remote
de-activation of the alarm output without interrupting
the Zone or Fire Logic outputs.
Status and Detector Outputs - Provide binary output
representations of the front panel digital displays for
remote indication of zone, detector and system status
(indicators not provided).
FIELD WIRING CONNECTOR
The R7494 Controller is typically furnished with a field
wiring connector backplate that incorporates pres-
sure type screw terminals for connecting the external
wiring and two circuit board edge connectors for
attaching to the controller. The R7494 controller is
available without a backplate when used with the
R6007 Relay Module. The use of a Q4004 Mounting
Cage is recommended for mounting the controller.
The backplate is attached to the rear of the cage to
allow easy removal of the controller without disturbing
the wiring. The controller is designed for installation
in a non-hazardous area.
SPECIFICATIONS
SPECTRAL SENSITIVITY RANGE—
UV: The UV sensor responds to radiation over the
range of 0.185 to 0.245 microns (1850 to 2450
angstroms).
IR: The single frequency infrared sensor responds to
radiation between 4.2 and 4.7 microns.
Figure1 illustrates the spectral response range of the
UV and IR sensors.
CONE OF VISION—
The C7052J has a 80 degree cone of vision with the
highest sensitivity lying along its central axis. See
Figure 6.
FLAME SENSITIVITY—
The C7052J5 with a part number DE5500 IR Sensor
Module (the sensor part number is printed on its side)
detects a 1 foot by 1 foot gasoline fire at 50 feet, a 2
foot by 2 foot JP4 fire at 100 feet and a 10 foot by 10
foot JP4 fire at 150 feet.
The C7052J with a part number DE3895 IR Sensor
Module (the sensor part number is printed on its side)
detects a 1 foot by 1 foot gasoline fire at 35 to 45 feet,
a 2 foot by 2 foot JP4 fire at 100 feet and a 10 foot by
10 foot JP4 fire at 150 feet.
RESPONSE TIME—
The response time of the detector is a function of fuel,
fire size, distance, orientation of the fire source and
the field programmable controller settings. With typi-
cal controller settings of 0.25 second gate length, 4
counts per gate, and 4 consecutive gates, the system
will respond to an intense fire signal in less than 2
seconds.
Response times of less than 1 second to an intense
fire signal can be achieved by setting the controller
for a 0.125 second gate length, 2 counts per gate,
and 3 consecutive gates.
INPUT VOLTAGE—
Controller and Detector
24 vdc nominal (18 vdc minimum, 32 vdc maximum)
with less than 1 volt of ripple.
POWER CONSUMPTION—
Controller: 1.5 watts typical, 3.5 watts maximum.
Detector: 1.0 watt typical, 3.5 watts maximum
(C7052J5 series: 5 watts maximum).
OUTPUT CIRCUIT RATINGS—
Open collector transistor outputs on the controller are
rated 100 ma dc, not to exceed 60 vdc. An internal
100 kilohm resistor is connected from the output to
circuit ground (terminal 2). External equipment that
may generate transients when switching (such as
relays) should have a transient suppression device
connected across the coil at the time of installation.
This will safeguard the output transistors in the con-
troller from possible damage. See Figure 4.
7 95-8311
0°
15°
30°
45°
15°
30°
45°
A1461
100
90
80
70
60
50
40
30
20
10
DETECTION
DISTANCE
(PERCENT)
100% REPRESENTS THE MAXIMUM DETECTION DISTANCE FOR A
GIVEN FIRE. THE SENSITIVITY INCREASES AS THE ANGLE OF
INCIDENCE DECREASES.
Figure 6—Cone of Vision

CONTROLLER TEMPERATURE RANGE—
Operating: –40°F to +158°F (–40°C to +70°C)
Storage: –67°F to +170°F (–55°C to +77°C)
DETECTOR TEMPERATURE RANGE—
Operating: –40°F to +167°F (–40°C to +75°C).
Storage: –67°F to +185°F (–55°C to +85°C)
DETECTOR HUMIDITY RANGE—
0 to 95% relative humidity.
RFI/EMI HARDENED—
Detector designed to meet RFI and EMI immunity
requirements of MIL STD 461, 462 and 463.
DETECTOR ENCLOSURE MATERIAL—
Copper-free aluminum (red) or 316 stainless steel,
with optional stainless steel mounting bracket.
DETECTOR ENCLOSURE RATINGS—
FM approved explosion-proof for Class I, Div. 1,
Groups B, C and D, Class II, Div. 1, Groups E, F and
G. CSA certified explosion-proof for Class I, Div. 1,
Groups C and D, Class II, Div. 1, Groups E, F and G.
BASEEFA/CENELEC certified flame-proof for EEX d
IIB T6. NEMA 4/IP66 enclosure rating.
DIMENSIONS—
See Figures 7, 8, 12 and 13.
SHIPPING WEIGHT—
R7494 Controller
4.4 pounds (2.0 kilograms)
C7052J Detector
Aluminum: 6.0 pounds (2.7 kilograms)
Stainless Steel: 14.0 pounds (6.4 kilograms)
8
C1047
3.38 (85.8 MM) 7.11 (181 MM)
7.81
(198 MM)
2.5 DIA.
(64 MM)
5.25
(133 MM)
CONDUIT ENTRY 3/4 NPT OR 25 MM
9.5 (242 MM)
7.0
(177 MM)
2.0
(50MM)
F234
Figure 8—Dimensions of R7494 Controller in Inches (Millimeters)
Figure 7—Detector Dimensions in Inches (Millimeters)

OPTIONS
Power supplies are available for operating the R7494
and C7052J from line (mains) voltage.
Q4004 Mounting Cage is designed for holding up to
eight micro-module devices and is recommended for
ease of installation and servicing. Mounting cages
that hold fewer modules are also available. Optional
filler panels (part number 002188-001) can be used to
cover unused sections of the mounting cage.
If the application requires the use of relay contacts,
the R6007 Auxiliary Relay Output Assembly can be
ordered for use in conjunction with the R7494
Controller. If supervised relay outputs or load moni-
toring capabilities are needed, the R6006 Auxiliary
Relay Output Module must be used. Rocker switch-
es on the side of the R6006 allow selection of time
delay and latching or non-latching operation of each
output. Contact the Field Support Group at Detector
Electronics for assistance in ordering a system to
meet the needs of a particular application.
Locking devices must be used on detector housings
to comply with applicable regulations in some areas
(BASEEFA/CENELEC).
Q1113 Air Shields for areas where there is an abnor-
mally high level of airborne contaminants. Two
Q1113 Air Shields are required for each detector.
Q9001G Swivel Assembly (part number 004404-
001) for easy mounting and sighting of assemblies.
RESPONSE CHARACTERISTICS
The response time of the detector is a function of fuel,
fire size, distance, orientation of the fire source and
the field programmable controller settings. As with all
fire tests, results must be interpreted according to the
individual application, taking into account all possible
variables (see the Application Guidelines section).
Typical response distances of the C7052J Detector to
various fuels are listed in Table 2. Each liquid fuel fire
(acetone, diesel, gasoline, methanol and toluene)
consisted of approximately one pint of fuel burned in
a 1 foot by 1 foot steel pan unless otherwise noted.
The excelsior (wood shaving) fire consisted of one
pound of wood shavings. The wood fire consisted of
a 10-inch by 10-inch crib (wood stack). The methane
fire was performed to FM standard, with the flame
approximately 30 inches high and 6 to 8 inches in
diameter. The detectors were sited to observe the fire
at center axis ±10 degrees. The controller sensitivity
and time delay settings were 4 counts per gate, 4
consecutive gates, and 0.25 second gate lengths.
APPLICATION GUIDELINES
Certain guidelines must be followed when using any
type of sensing device as a fire detector. This
involves not only recognizing the strengths and
advantages of a particular device, but also under-
standing its limitations.
It is also important to note that in any system that uses
two or more sensors to produce a fire signal, the
detector will be disabled should one of its sensors
fail. The Automatic oifeature will warn of such fail-
ure. Routine manual testing and checking of the sys-
tem is recommended for increased system reliability.
Potential radiation sources in the environment must
also be carefully considered. A UV sensor will
respond to sources of UV besides fire, such as elec-
tric arc welding, lightning, x-rays and gamma radia-
tion. The C7052J has been designed to ignore
steady state infrared sources that do not have a flick-
er frequency characteristic of a fire, however, it
should be noted that if these steady state infrared
sources are hot enough to emit adequate amounts of
infrared radiation in the response range of the IR sen-
sor and if this radiation becomes interrupted from the
view of the detector in a pattern characteristic of a
flickering flame, the IR sensor can respond. Any
object having a temperature greater than 0° Kelvin
(–273°C) emits infrared radiation. The hotter the
object, the greater the intensity of the emitted radia-
tion. See Figure 9. The closer the infrared source is
to the detector, the greater the potential for the IR
sensor to produce an alarm. The IR sensor can
respond to IR radiation sources that can meet the
amplitude and flicker requirements of the detector
such as vibrating hot objects. Although the C7052J
Detector is designed to reduce false actuations, cer-
tain combinations of ambient radiation must be avoid-
ed. For example, if IR radiation with an intensity that
exceeds the fire threshold of the IR sensor should
reach the detector as a flickering signal, and if at the
same time an electric arc welding signal also reaches
the sensors, an alarm output will be generated.
The C7052J ignores arc welding beyond 15 feet from
the detector. However, the UV sensor will respond to
9 95-8311
Table 2—C7052 Typical Response Distance
Fuel Distance from C7052
Acetone 45 feet (13.7 meters)
Diesel 40 feet (12.2 meters)
Gasoline 50 feet (15.2 meters)
Methane 35 feet (10.7 meters)
Wood Shavings (Excelsior) 50 feet (15.2 meters)
Wood Stack (Crib) 50 feet (15.2 meters)

the intense UV radiation generated by the arc weld-
ing, and at distances closer than 15 feet the heated
metal from the welding can become a false alarm
source for the IR sensor.
Another important fact regarding a radiation detector
of any type is that radiation must reach the detector in
order for it to respond. Care must be taken to keep
physical obstructions out of the line of view of the
detector. In addition, UV or IR absorbing gases or
vapors must not be allowed to accumulate between
the detector and the protected hazard. See Table 3
for a listing of these substances. Smoke will also
absorb radiation, therefore, the detector should not
be mounted close to the ceiling or other areas where
smoke can accumulate.
It is important to keep the detector viewing windows
as free of contaminants as possible in order to main-
tain maximum sensitivity and to assure proper opera-
tion of the flame detection system. Commonly
encountered substances that can significantly attenu-
ate UV and/or IR radiation include, but are certainly
not limited to, the following:
Silicones
Oils and greases
Ice buildup
Dust and dirt buildup
Paint overspray
The oitest feature is designed to register an oifault
when the detector sensitivity is reduced to approxi-
mately 50% of its maximum detection range. For
maximum system reliability, it is recommended that
the detector viewing windows be cleaned on a regu-
larly scheduled basis. (Refer to the “Maintenance”
section for additional information regarding detector
maintenance.) The use of model Q1113 Air Shields
can help extend the time period between required
maintenance.
The C7052J is designed to be resistant to interfer-
ence from EMI and RFI. It will not respond to a 5
watt walkie-talkie at a distance of greater than 1 foot.
The C7052J uses a single frequency IR sensing
device with detection limited to the hot CO
2
emission
peak, therefore, it cannot be used to detect fires that
do not contain carbon, such as hydrogen, sulfur,
burning metals, or other non-hydrocarbons without
thorough testing.
10
Table 3—Radiation Absorbing Gases and Vapors
The following 38 substances exhibit significant UV
absorption characteristics. These are also generally
hazardous vapors. While usually of little consequence
in small amounts, these gases can restrict UV detec-
tion if they are in the atmosphere in heavy concentra-
tions. It should also be determined whether or not
large amounts of these gases may be released as a
result of a fire-causing occurrence.
Acetaldehyde Methyl Methacrylate
Acetone Alpha-Methylstyrene
Acrylonitrile Naphthalene
Ethyl Acrylate Nitroethane
Methyl Acrylate Nitrobenzene
Ethanol Nitromethane
Ammonia 1-Nitropropane
Aniline 2-Nitropropane
Benzene 2-Pentanone
1,3 Butadiene Phenol
2—Butanone Phenyl Clycide Ether
Butylamine Pyridine
Chlorobenzene Hydrogen Sulfide
1-Chloro-1-Nitropropane Styrene
Chloroprene Tetrachloroethylene
Cumene Toluene
Cyclopentadiene Trichloroethylene
O-Dichlorobenzene Vinyl Toluene
P-Dichlorobenzene Xylene
If UV-absorbing gases can be a factor in a given
application, precautionary measures should be taken.
Detectors can be placed closer to the potential haz-
ard area, and/or the sensitivity of the detection sys-
tem can be increased. Contact the factory for further
details.
Substances such as methane, propane, camphor,
butane, hexane and octane are not UV absorbing.
104
103
102
101
1
10–1
10–2
10–3
10–40.4 0.6 0.8 1 2 4 6 8 10 20 30
RADIANT EMITTANCE WATTS
(CM ) (MICRON)
2
WAVELENGTH (MICRONS)
6000°K
2000°K
250°K
500°K
300°K
4000°K
1000°K
A0576
Figure 9—Blackbody Spectral Emittance

INSTALLATION
DETECTOR POSITIONING
When determining the proper number and positioning
of detectors needed for adequately protecting any
given installation, it is essential to consider the cone
of vision of the detector. The C7052J Detector has a
nominal 80 degree cone of vision with the highest
sensitivity along its central axis. Refer to Figure 6.
Careful observation of this graph reveals that at 50
percent of the maximum detection distance, the cone
of vision is still 80 degrees. As the detection distance
increases beyond 50 percent, the cone of vision
gradually decreases. For example, the C7052J will
detect a 1 foot by 1 foot gasoline fire at 50 feet.
Therefore, we can assume that at 25 feet (50% maxi-
mum distance) the cone of vision will be 80 degrees.
If the fire increases in size, both the maximum detec-
tion distance and the cone of vision at longer dis-
tances will be increased.
It is also important to note that as the distance
increases between the detector and the fire source,
the time needed for the detector to respond to a fire
of a given size also increases (fastest response
requires maximum fire signal). The intensity of the
radiation reaching the detector decreases with dis-
tance. For fastest response time, locate the detector
as close as possible to the anticipated fire source.
The following recommendations should be observed
in designing or installing any fire detection system:
— Use enough detectors to adequately cover the
protected area with overlapping cones of vision.
— For fastest response time, position the detectors
as close as possible to the anticipated fire
source.
— Aim the detector as directly as possible at the
anticipated fire source.
— If possible, conduct actual flame tests to verify
correct detector positioning and proper system
operation.
Whenever possible, the detector should be positioned
in a manner that will minimize the buildup of contami-
nants on the viewing window and oiring.
Substances such as snow, ice, dirt, oil, paint over-
spray and numerous other commonly encountered
materials are capable of attenuating UV or IR radia-
tion and adversely affecting detector response.
For outdoor applications, the detector should be
aimed downward to minimize the buildup of water or
ice on the detector viewing window and to prevent it
from scanning the horizon. This minimizes the
response to distant radiation sources outside the pro-
tected area.
The detector should not be placed where smoke can
obscure its view of the hazardous area. For indoor
applications, if dense smoke is expected to accumu-
late at the onset of a fire, mounting the detector on a
side wall a few feet (1 meter) down from the ceiling
will normally allow enough time for the unit to respond
before it is affected by rising smoke. The detector
should be located where it can be easily accessed for
periodic maintenance, testing and cleaning.
WIRING REQUIREMENTS
The system should be wired using four conductor
shielded cable, at least 18 gauge (1.024 mm diame-
ter). The length of cable should be considered when
wiring the system to ensure that a minimum input volt-
age of 18 vdc is present at the detector. The cable
length should not exceed 2000 feet. In applications
where the wiring cable is installed in conduit, the con-
duit should not be used for wiring to other electrical
equipment. Foil type shielded cable is recommended
to protect from electromagnetic and radio frequency
interference. When using cables with shields, the
shield should be insulated at the detector and
grounded only at the control cabinet.
NOTE
It is important to use cable that is suitable for the
installation environment. In applications involv-
ing high humidity or salt water, use a cable that
is made specifically for harsh, salt water environ-
ments. In all cases, typical cable insulation
resistance should be at least 100 megohms. If
the resistance drops below 10 megohms, the
cable could be deteriorating and should be
replaced to avoid shorting. When testing the
insulation resistance, disconnect the leads from
the detector/controller before connecting the
megohmmeter (insulation tester) to the cable.
Since moisture can be detrimental to electronic
devices, it is important that moisture not be allowed to
come in contact with the electrical connections of the
system. Moisture in the air can become trapped with-
in sections of conduit, therefore the use of conduit
seals is required to prevent damage to electrical
connections caused by condensation within the con-
duit. These seals must be water-tight and explosion-
proof and are to be installed even if they are not
required by local wiring codes. A seal must be locat-
ed as close to the C7052J as possible. In no case
should this seal be located more than 18 inches (46
cm) from the unit. If a conduit swivel is used, the seal
must be located between the swivel and the detector.
When an explosion-proof installation is required, an
additional seal must also be installed at any point
where the conduit enters a non-hazardous area.
When pouring a seal, the use of a fiberdam is
11 95-8311

required to assure proper formation of the seal. The
seals should never be poured in temperatures that
are below freezing, since the water in the sealing
compound will freeze and the compound will not dry
properly. Contamination problems can then result
when temperatures rise above the freezing point and
the compound thaws. The shielding of the cable
should be stripped back to permit the seal to form
around the individual leads, rather than around the
outside of the shield. This will prevent any siphoning
action that might occur through the inside of the
shield. The electrical continuity of the shield must be
maintained through the seal via the shield drain wire.
Moisture in the air can be trapped within sections of
conduit and can condense and accumulate at the
base of vertical conduit runs. To eliminate this condi-
tion, explosion-proof drains and breathers should be
installed to automatically bleed off accumulated
water.
It is recommended that the detector be oriented with
the conduit opening at the bottom or at either side of
the device. This will reduce the possibility of moisture
entering the junction box through the conduit entry
and also ensure that the oitest lamps are not in a
position that would make the detector overly suscepti-
ble to oifaults. Whenever possible, slope the con-
duit run downward from the detector. Do not use
conduit runs that enter the device from the top. See
Figure 10.
DETECTOR MOUNTING AND WIRING PROCEDURE
The following procedure should be used for mounting
and wiring the C7052J.
1. Detectors should be located in positions best
suited for covering the area to be protected.
Whenever practical, they should be placed where
they will be easily accessible for cleaning and
other periodic servicing. Particular attention
should also be paid to potential false alarm
sources within the cone of vision of the detector,
such as distant arc welding, rotating fan blades,
surface vibration of an IR source, and movement
of people or machines between the detector and
an IR source, all of which could allow a flickering
IR signal to reach the detector. Rain or ice can
absorb radiation, which can reduce the capability
of the detector. For outdoor applications, aim the
detector downward to minimize the buildup of
water or ice on the detector viewing windows and
to prevent the cone of vision from scanning the
horizon. This minimizes response to distant radi-
ation sources outside the protected area.
NOTE
The wiring procedures in this manual are intend-
ed to ensure proper functioning of the device
under normal conditions. However, because of
the many variations in wiring codes and regula-
tions, total compliance to these ordinances can-
not be guaranteed. Be certain that all wiring
12
oiRING OPENING DOWN
CONDUIT SEAL REQUIRED WITHIN 18 INCHES
OF DETECTOR. DETECTOR MUST BE ORIENTED
WITH CONDUIT ENTRY AT BOTTOM OR SIDE TO
ELIMINATE DRAINAGE INTO JUNCTION BOX.
*oiTEST LAMPS AT TOP OR SIDE
oiTEST LAMP
*oiTEST LAMP (2)
IR SENSOR HOUSING
UV SENSOR HOUSING
A1462
Figure 10—Front View of the C7052 Detector

complies with applicable regulations that relate to
the installation of electrical equipment in a haz-
ardous area. If in doubt, consult a qualified elec-
trician before wiring the system.
2. Remove the junction box cover assembly from the
base by loosening the six screws on the cover
(see Figure 11).
3. Mount the detector junction box base and mount-
ing bracket assembly on the wall or ceiling. See
Figures 12 and 13 for dimensions of the mounting
bracket. The mounting surface should be free of
excessive heat and vibration.
13 95-8311
E946
JUNCTION BOX
JUNCTION BOX COVER
MOUNTING PIN
IR TEST LAMPS (2)
O-RING
IR SENSOR HOUSING
IR oiRING
INDEX PIN
UV SENSOR MODULE
O-RING
UV TEST LAMP OPENING
UV SENSOR HOUSING
UV oiRING
IR SENSOR MODULE
IR CONNECTOR PLUG
JUMPER PLUG "J" (MUST BE REMOVED)
UV TERMINAL BLOCK
Figure 11—C7052J Detector Part Identification
2–1/2 (64 MM) DIA.
2.00 (50.8 MM) DIA.
0.25 (6.4 MM)
DIA. (3)
120°± 2°(2)
A1305
5-1/4 INCHES
(133 MM)
2-1/2 INCHES
(64 MM)
MOUNTING BASE
1/2 INCH NUT USED TO ADJUST
ELBOW TO DESIRED ANGLE
1-3/8 INCH NUT USED TO ROTATE
SWIVEL/DETECTOR ASSEMBLY
TO DESIRED POSITION
3/4 INCH NUT USED TO
SECURE DETECTOR
BRACKET TO SWIVEL MOUNT
JUNCTION BOX MOUNTING
BRACKET (ATTACHES
WITH TWO ENCLOSED
FLATHEAD SCREWS)
B1303
Figure 12—Mounting Base Dimensions Figure 13—Q9001G Swivel Mounting Bracket Dimensions

NOTE
Do not wire the system, or plug in or remove the
sensor modules with power applied.
4. Figure 14 shows the detector terminal block.
Letter designations correspond to connections as
indicated below.
A = +24 vdc
B = detector output signal
C = circuit ground
D = oicontrol signal
Minimum requirements for wiring the detector are
for the B-lead (signal) to be shielded. It is pre-
ferred that the A-lead, C-lead, and D-lead also be
shielded to provide maximum immunity to
EMI/RFI. The wiring procedure below is the pre-
ferred method of detector to controller wiring.
Refer to Figure 15 for an example of detector to
controller wiring.
a. Connect the B-lead shields to the earth
ground connection (terminal 64) of the con-
troller.
b. Be certain that the shield is NOT connected
to the detector at terminal “C” (circuit
ground) or any other points.
c. Connect the C-leads of the detectors to ter-
minal 2 (circuit ground) of the controller.
d. Connect a non-polarized 0.47 microfarad
250 vdc capacitor from terminal 64 to termi-
nal 2. This places the earth ground and the
circuit ground at the same ac potential, mini-
mizing induction of noise into the system
through the detector cable.
5. Check to make sure that all wiring is correct. If
conduit is used, pour the conduit seals and allow
them to dry.
6. If the UV and/or IR sensor modules are already
installed in the detector housing, proceed to step
12. If the sensors are not installed, remove the
applicable sensor housings from the junction box
cover (see Figure 11). If the detectors are
equipped with a cover locking device (see Figure
16), loosen the clamp and disengage the “catch”
from the blind hole. The tool required is a 5/32-
inch hexagonal (Allen) wrench.
7. If the UV sensor module is already installed, pro-
ceed to step 9. If the UV module is not installed,
remove the UV sensor module from its shipping
package.
8. Determine the proper orientation for the UV mod-
ule by lining up the long index pin on the terminal
block with the hole in the printed circuit board of
the module. See Figure 11. Firmly press the
module into place on the terminal block, taking
care not to touch the glass envelope of the sensor
module, since fingerprints can absorb UV radia-
tion and reduce the sensitivity of the sensor.
IMPORTANT
If the UV sensor module is supplied with a
jumper plug “J” as shown in Figure 17, remove
the jumper plug from the detector tube module
and discard it. Jumper plug “J” is supplied for
installations in which the tube module is used
with other detector models.
NOTE
The C7052J contains semiconductor devices
that are susceptible to damage by electrostatic
discharge. An electrostatic charge can build up
on the skin and discharge when an object is
touched. Therefore, use caution when handling
the detector, taking care not to touch the termi-
nals or electronic components. For more infor-
mation on proper handling, refer to Service
Memo form 75-1005 at the front of this manual.
9. If the IR sensor is already installed, proceed to
step 12. If the IR sensor is not installed, remove
the IR module from its shipping package (avoid
touching the IR sensing element at the top of the
module). Two IR sensor designs exist; the
DE5500 is electrically connected via a wire har-
ness on the junction box that must be threaded
through the sensor module to a connector at the
top of the module (see Figure 18), the DE3895
plugs directly onto a terminal block in the base of
the IR housing via connectors on the bottom of
the IR sensor module (see Figure 11).
10. If the IR sensors are the DE3895 type that electri-
cally connects directly onto the terminal block,
install them by lining up the connection pins using
the index pin to properly orient the module. Press
the sensor firmly into place.
11. If the IR sensor is the DE5500 type that connects
via a wire harness (Figure 18), thread the wire
leads and keyed connector plug through the slot-
ted opening on the side of the IR module. Plug
the IR module into the two banana plugs inside
the junction box cover. If repositioning is neces-
sary to properly align the oilamps (as described
in the “NOTE” below), this module can be rotated
180° and remounted on the banana plugs.
14

15 95-8311
D0947
+24 VDC (A)
OUTPUT SIGNAL (B)
CIRCUIT GND (C)
oiSIGNAL (D)
EARTH GND
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
+24 VDC
CIRCUIT GROUND
+24 VDC
B1 - INPUT SIGNAL
B2 - INPUT SIGNAL
B3 - INPUT SIGNAL
B4 - INPUT SIGNAL
B5 - INPUT SIGNAL
B6 - INPUT SIGNAL
B7 - INPUT SIGNAL
B8 - INPUT SIGNAL
D1 oiDRIVER
D2 oiDRIVER
D3 oiDRIVER
D4 oiDRIVER
D5 oiDRIVER
D6 oiDRIVER
D7 oiDRIVER
D8 oiDRIVER
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
NOT USED
NOT USED
DATA STROBE IN
NOT USED
NOT USED
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
ZONE OUTPUT 1
ZONE OUTPUT 2
ZONE OUTPUT 3
ZONE OUTPUT 4
ZONE OUTPUT 5
ZONE OUTPUT 6
ZONE OUTPUT 7
ZONE OUTPUT 8
FIRE LOGIC “A”/ DATA STROBE OUT
FIRE LOGIC “B”
ALARM OUTPUT
EXTERNAL RESET/INHIBIT
OUTPUTS INHIBITED
FAULT OUTPUT
EXTERNAL ACCEPT
STATUS & DET. OUTPUT S1
STATUS & DET. OUTPUT S2
STATUS & DET. OUTPUT S3
STATUS & DET. OUTPUT S4
STATUS & DET. OUTPUT S5
STATUS & DET. OUTPUT S6
STATUS & DET. OUTPUT S7
STATUS & DET. OUTPUT S8
DATA BUS 0
DATA BUS 1
DATA BUS 2
DATA BUS 3
DATA BUS 4
DATA BUS 5
DATA BUS 6
DATA BUS 7
EARTH GROUND
J2
J1 R7494 CONTROLLER
A
B
C
D
A
B
C
D
A
B
C
D
A
B
C
D
A
B
C
D
A
B
C
D
A
B
C
D
T1 (+)
T7 (B4)
T2 (–)
T15 (D4)
A
B
C
D
A
B
C
D
T1 (+)
T6 (B3)
T2 (–)
T14 (D3)
A
B
C
D
T1 (+)
T8 (B5)
T2 (–)
T16 (D5)
B1274
0.47 uf
250 VDC
A
B
C
D
A
B
C
D
T1 (+)
T9 (B6)
T2 (–)
T17 (D6)
A
B
C
D
A
B
C
D
T1 (+)
T10 (B7)
T2 (–)
T18 (D7)
A
B
C
D
A
B
C
D
T1 (+)
T11 (B8)
T2 (–)
T19 (D8)
24 VDC
+–
NO. 1
NO. 2
NO. 3
NO. 4
NO. 5
NO. 6
NO. 7
NO. 8
C7052J DETECTOR
Figure 14—Detector Terminal Block
Figure 15—Detector and Power Connections

NOTE
The two oilamps on the DE5500 IR sensor
should be at the top or side of the detector (when
viewed from the front) and the opening on the oi
ring should be at the bottom. See Figure 10.
This will ensure proper operation of the oisys-
tem and also minimize the accumulation of mois-
ture and contaminants between the oiring and
the viewing window. (The oilamps on the IR
sensor are identified as oblong in shape and
clear in color.)
12. Connect the keyed connector plug to the 4-pin
connector on the DE5500 IR module. Tuck the
leadwires inside the module to prevent binding or
wire damage when installing or removing the sen-
sor housing.
13. Check the O-rings on both sensor housings to be
sure that they are in good condition and are fitted
properly, then re-install the sensor housings on
the junction box cover. (See the “Maintenance”
section for information regarding care of O-rings.)
The sensor housing with the large viewing window
is for the UV detector and the sensor housing with
the small window is for the IR detector. Hand
tighten the sensor housings into the base until the
O-rings are fully seated to maintain the explosion-
proof and watertight integrity of the housing. If
the unit is equipped with cover locking clamps,
loosen the clamps sufficiently so that the clamp
catches can be seated in the blind holes on the
junction box cover. Fasten the clamps securely
using a 5/32 inch hexagonal (Allen) wrench. (See
Figure 16.)
14. Re-install the junction box cover, making sure that
the center nine-pin connector on the cover is
properly aligned with the connector in the junction
box. The six screws must be tight to ensure a
metal to metal fit to maintain explosion-proof and
watertight integrity of the junction box.
15. Inspect and clean (if necessary) the detector
viewing windows and oirings by following the
instructions in the “Maintenance” section.
16. The opening of the oirings should be pointed
down to minimize the accumulation of moisture or
contaminants behind the ring (see Figure 10).
Verify that the oitest lamp is at the top or side of
each sensor. Note that Figure 10 shows the
DE5500 IR module with the test lamps located
together on one side of the edge. The DE3895 IR
module has test lamps located directly opposite
one another. In both cases, ensure that no test
lamp is positioned at the bottom when the detec-
tor is installed.
16
A1331
IR MODULE 4–WIRE CONNECTOR PLUG
Figure 18—IR Module with Four-Wire Connector
A0971
REMOVE JUMPER PLUG
Figure 17—Jumper Plug
BLIND HOLE
COVER
LOCKING
ASSEMBLY
CATCH
CLAMP
SCREW
STRAP
BARREL
LENS CAP
A1078
Figure 16—Cover Locking Assembly (Optional)

17. If the detector is so equipped, install the air
shields on each sensor housing, then connect the
air supply line to the air shields.
NOTE
Be sure that the detector is correctly aimed at the
potential hazard and that no obstructions inter-
fere with its line of vision. In addition, UV and/or
IR absorbing gases (Table 3) should not exist
between the detector and the potential hazard.
CONTROLLER INSTALLATION AND WIRING
The R7494 Controller must be mounted in a non-haz-
ardous area. The optional Q4004 Mounting Cage is
designed to hold up to eight modules in a 19 inch
instrument rack. Other mounting cages are available
to accomodate 1, 2, 3, or 4 units. These mounting
cages can also house relay output modules, voltage
converters, or other micro-module equipment that is
used in conjunction with the R7494 Controller as part
of the total protection system. See Figure 19 for illus-
tration and dimensions.
ELECTRICAL CONNECTIONS
All electrical connections are made to the field wiring
connector that is furnished with the controller. Figure
20 shows the terminal configuration for the controller.
Power to the R7494 Controller and C7052J Detectors
may be furnished by external 24 volt batteries, a regu-
lated dc power supply, or optional Det-Tronics volt-
age converters.
Terminal 1 — Connect to the positive (+) side of an
external 24 vdc power source.
Terminal 2 — Connect to the negative (-) side of the
dc power source (circuit ground). The C terminals on
the detectors must also be connected to circuit
ground.
Terminal 3 — + 24 vdc (same as terminal 1) for con-
nection to the A terminals on the detectors.
Terminal 4 to 11 — Connect to the B terminals (signal)
of the corresponding detectors.
17 95-8311
(A)
(B)
(C)
6.97
(177.1)
1.48 (37.59)
4.0
(101.6)
A1463 ALL CONTROLLER CAGES REQUIRE A MINIMUM OF 10.12 INCHES (257.1 MM) DEPTH CLEARANCE
Figure 19—Q4004 Mounting Cage Dimensions in Inches (Millimeters)
PART NUMBER CONTROLLER
005269-XXX POSITIONS FOR: HT: DIM. (A) DIM. (B) DIM. (C)
FIRE GAS INCH MM INCH MM INCH MM
–001 8 16 4U 19.00 482.6 18.30 464.8 17.36 440.9
–002 6 12 4U 15.06 382.6 14.36 364.7 13.42 340.9
–003 4 8 4U 11.13 282.6 10.43 264.9 9.49 241.1
–004 3 6 4U 9.16 232.7 8.46 214.9 7.52 191.0
–005 2 4 4U 7.19 182.7 6.49 164.9 5.55 141.0
–006 1 2 4U 5.22 132.6 4.52 114.8 3.58 90.9

Terminal 12 to 19 — Connect to the D terminals (oi
driver) of the corresponding detectors.
Terminal 20 to 27 — Data Bus Out - Connect to the
“Data Bus In” terminals of the next “downstream” con-
troller when common (intercontroller) voting is cho-
sen.
Terminal 28 and 29 — Do not use.
Terminal 30 — Data Strobe In — Connect to the “Data
Strobe Out” terminal (Terminal 41) of the previous
controller when common (intercontroller) voting is
chosen.
Terminal 31 and 32 — Not used.
Terminal 33 to 40 — Corresponding UV/IR Fire Alarm
zone (detector) outputs.
Terminal 41 — Fire Logic A/Data Strobe Out. Fire
Logic A output is used when separate controller vot-
ing is chosen. Data Strobe output is connected to
next “downstream” controller when common (inter-
controller) voting is chosen.
Terminal 42 — Fire Logic B output is used when
either separate or common voting is chosen.
Terminal 43 — Alarm output.
Terminal 44 — External Reset/Inhibit, a normally open
switch connected between terminal 44 and circuit
ground (terminal 2) allows the controller to be reset or
inhibited from a remote location.
Terminal 45 — Outputs Inhibited, for connecting an
indicating device to signal when the outputs are inhib-
ited due to the controller keylock switch position or
the External Reset/Inhibit switch.
Terminal 46 — Fault Output, for connecting an indi-
cating device to signal when a fault condition devel-
ops. The fault output is activated (energized) when
power is applied to the system and de-activated (de-
energized) by loss of power or other fault conditions.
Terminal 47 — External Accept, a normally open
switch connected between terminal 47 and circuit
ground (terminal 2) allows remote de-activation of the
alarm output without interrupting the zone and fire
logic outputs.
Terminal 48 to 55 — Status and Detector outputs pro-
vide binary output representations of the front panel
digital displays for zone, detector and system status.
Tables 4 and 5 list the identification codes and the
logic states of the “Fault” and “Outputs Inhibited” bits
for the various status conditions. Note: Under “nor-
mal” (no-fault) conditions, the Fault output is ener-
gized (logic 1).
Terminal 56 to 63 — Data Bus In, connect to “Data
Bus Out” terminals of the previous controller when
common (intercontroller) voting is chosen.
Terminal 64 — Earth Ground terminal is connected to
the controller chassis and should be connected to the
nearest earth ground connection.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
+24 VDC
CIRCUIT GROUND
+24 VDC
B1 - INPUT SIGNAL
B2 - INPUT SIGNAL
B3 - INPUT SIGNAL
B4 - INPUT SIGNAL
B5 - INPUT SIGNAL
B6 - INPUT SIGNAL
B7 - INPUT SIGNAL
B8 - INPUT SIGNAL
D1 oiDRIVER
D2 oiDRIVER
D3 oiDRIVER
D4 oiDRIVER
D5 oiDRIVER
D6 oiDRIVER
D7 oiDRIVER
D8 oiDRIVER
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
DATA BUS OUT
NOT USED
NOT USED
DATA STROBE IN
NOT USED
NOT USED
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
ZONE OUTPUT 1
ZONE OUTPUT 2
ZONE OUTPUT 3
ZONE OUTPUT 4
ZONE OUTPUT 5
ZONE OUTPUT 6
ZONE OUTPUT 7
ZONE OUTPUT 8
FIRE LOGIC “A”/ DATA STROBE OUT
FIRE LOGIC “B”
ALARM OUTPUT
EXTERNAL RESET/INHIBIT
OUTPUTS INHIBITED
FAULT OUTPUT
EXTERNAL ACCEPT
STATUS & DET. OUTPUT S1
STATUS & DET. OUTPUT S2
STATUS & DET. OUTPUT S3
STATUS & DET. OUTPUT S4
STATUS & DET. OUTPUT S5
STATUS & DET. OUTPUT S6
STATUS & DET. OUTPUT S7
STATUS & DET. OUTPUT S8
DATA BUS 0
DATA BUS 1
DATA BUS 2
DATA BUS 3
DATA BUS 4
DATA BUS 5
DATA BUS 6
DATA BUS 7
EARTH GROUND
J2
J1
B991
R7494
Figure 20—Terminal Configuration
Table 4—Relationships of ZONE and DETECTOR Display
to the Status Outputs
18
Front Panel Display Status Outputs
Zone S1 S2 S3 S4 S5
1 1000X
2 0100X
3 1100X
4 0010X
5 1010X
6 0110X
7 1110X
8 0001X