Det-Tronics OPECL User manual

IMPORTANT
Be sure to read and understand the entire instruc-
tion manual before installing or operating the gas
detection system. This product is intended to pro-
vide early warning of the presence of a flammable
or explosive gas mixture. Proper device installa-
tion, operation, and maintenance is required to
ensure safe and effective operation.
APPLICATION
The Open Path Eclipse™Model OPECL is an open path
infrared gas detection system that provides continuous
monitoring of combustible hydrocarbon gas concentra-
tions in the range of 0 to 5 LEL-meters. Standard sys-
tem outputs include an electrically isolated/non-isolated
4-20 mA dc current output, with HART communication
and RS-485 MODBUS communication.
The system consists of two stainless steel modules — a
transmitter and a receiver, along with mounting fixture
hardware. Both modules are powered from an external
24 volt DC supply. The receiver provides the measure-
ment signal outputs, and is furnished with an onboard
"status indication" LED and an internal magnetic calibra-
tion switch. The transmitter houses redundant xenon
flashlamps. Both modules are installed at approximate-
ly the same elevation and must be aligned to point
directly at one another. No direct electrical interconnec-
tion between the two modules is required.
The Open Path Eclipse is ideal for use in harsh outdoor
environments and is certified for use in Class I, Division
1 and Division 2 hazardous areas. It can be used as a
stand-alone detector, or as part of a larger facility pro-
tection system using other Det-Tronics equipment such
as the R8471 Series Controller or the Eagle Quantum
Premier Fire and Gas Detection/Releasing System.
INSTRUCTIONS
Infrared Hydrocarbon Gas Detector
Open Path Eclipse™
Model OPECL
1.1 ©Detector Electronics Corporation 2004 1/04 95-8556
DET-TRONICS®

295-85561.1
OPERATION OVERVIEW
THEORY OF OPERATION
The OPECL transmitter module illuminates a direct lin-
ear path ending at the OPECL receiver module. As
flammable hydrocarbon gases intersect the light beam
between the two modules, certain IR wavelengths are
absorbed by the gas, while other IR wavelengths are
not. The amount of IR absorption is determined by the
concentration of the hydrocarbon gas. A pair of optical
detectors and associated electronics located in the
receiver module measure the absorption. The change
in intensity of the absorbed light (active signal) is mea-
sured relative to the intensity of light at a non-absorbed
wavelength (reference signal). The microprocessor
computes the gas concentration and converts the value
into a 4 to 20 milliampere current output signal, which is
then communicated to external control and annunciation
systems. No filter wheel motors or other moving parts
are utilized in either module.
LAMP REDUNDANCY
The OPECL transmitter provides a unique operational
feature. A xenon lamp illuminates the linear detection
path from the transmitter to the receiver. In the event
that the primary lamp fails, the back-up lamp is brought
into service. The receiver recognizes this condition by
the change in flash pulse coding and responds by initi-
ating a “failed lamp” warning signal to indicate that the
back-up lamp is in use. Total system operation is main-
tained, with no loss of sensitivity or detection perfor-
mance. In this mode of operation, the following occur:
1. The indicator LED turns amber.
2. The 4-20 mA signal drops from a normal 4 mA to 2.4
mA. The analog output value is overridden if the gas
level exceeds 0.5 LEL-meters. All gas alarm signals
will occur as when operating with the primary lamp.
3. HART and MODBUS communication warn of a
“failed lamp” condition.
Service should be arranged as soon as possible. A
new transmitter module should be installed.
DETECTABLE GASES
OPECL is capable of detecting most hydrocarbon
gases and vapors including methane, ethane, propane,
butane, and propylene. Gas type and other operational
parameters are selected via digital communications.
The factory calibrated setting is methane.
OUTPUTS
An isolated 4 to 20 mA current loop corresponding to 0
to 5 LEL-meters is provided for connection to analog
input devices such as gas controllers, logic controllers,
or distributed control systems (DCS). (Relay outputs will
be available in a future release.)
COMMUNICATION
The standard OPECL system provides an analog 4-20
mA signal output, with HART and RS-485 MODBUS seri-
al communication from the receiver module.
RECORDING CAPABILITY
Non-volatile memory is provided to save the 10 most
recent calibrations, alarm/fault events, and
minimum/maximum operating temperature history. A
real time clock is provided to record operating service
time and to time stamp events. This information is
accessible using HART and MODBUS communication.
OPERATION
MODULE IDENTIFICATION
While the OPECL transmitter and receiver modules
appear physically identical, each module is labeled as
“transmitter” or “receiver” on the rear cover. The physi-
cal mounting requirements for both modules are gener-
ally identical. However, there are functional and electri-
cal characteristic differences as identified in Table 1.

395-85561.1
Characteristic Transmitter (Tx) Receiver (Rx)
Functional Description Contains primary and backup xenon
flashlamps, and generates optical ener-
gy to enable hydrocarbon detection.
Contains opto-electronics, signal pro-
cessing and output drivers, and diagnos-
tic electronics.
Power Consumption 6.0 watts nominal @ 24 Vdc.
12.2 watts peak @ 24 Vdc.
6.0 watts nominal @ 24 Vdc.
12.2 watts peak @ 24 Vdc.
Electrical Connections 2 power connections only.
(+24 Vdc and –24 Vdc).
From 3-7 connections depending upon
specific configuration (separate power
and signal cables recommended).
Onboard HART Communication Port Factory use only. Recommended for connection to hand-
held HC275/375 HART communicator
for system setup, commissioning, and
diagnostics.
Onboard LED Indicator Indicates normal, fault, and backup lamp
operation status.
Green indicates normal operation.
Red indicates fault condition.
Amber indicates operation in “back-up
lamp” mode.
Indicates normal, alarm, fault, and cali-
bration status.
Green indicates normal operation.
Blinking red indicates low gas alarm con-
dition.
Steady red indicates high gas alarm con-
dition.
Amber indicates operation in “back-up
lamp” mode or system fault.
Calibration status is indicated by a
steady red indication after Calibration
command.
LED operation for fault status is non-
latching. LED operation for gas alarms
is configurable for latching/non-latching.
Magnetic Calibration Switch
(See Figure 1 for switch location.)
Non-functional Momentary activation provides reset
function for latched alarm outputs.
Activation for longer than 2 seconds will
initiate calibration.
Factory Default Settings No programmable options Factory calibrated for methane, 0-5 LEL-
meters full scale. See Table 2 for
receiver factory default settings. HART
communication is required to change the
factory default settings.
Table 1—Functional and Electrical Comparison of Transmitter and Receiver
PLACE CALIBRATION MAGNET
HERE TO ACTIVATE INTERNAL
REED SWITCH
Figure 1—Location of Magnetic Switch

OPERATING MODES
The OPECL has four operating modes: warm-up, nor-
mal, alignment and calibrate.
Warm-up
Warm-up mode is entered upon application of 24 Vdc
operating power. During warm-up, the 4-20 mA current
loop output will indicate warm-up, the indicating LED is
yellow, and the alarm outputs are disabled. The warm-
up mode lasts nominally two minutes after power-up.
Normal
After warm-up mode is completed, the device automati-
cally enters the Normal mode, and all analog and alarm
outputs are enabled.
Alignment
The OPECL modules must be properly aligned before
normal operation is attained. There are two alignment
procedures:
1. Basic Alignment requires the OPECL Alignment Kit.
A handheld HART communicator is recommended,
but not required.
2. Full Alignment requires the OPECL Alignment Kit
and a handheld HART communicator.
Calibrate
After alignment is completed, zero calibration is
required. Fugure calibration of the OPECL is normally
not required; however, the user has the option to verify
proper calibration or to perform calibration procedures if
necessary. Refer to the "Calibration" section in this
manual for details.
4 TO 20 MA CURRENT LOOP OUTPUT
OPECL provides an isolated, linear current loop output
that is proportional to the detected gas level. Fault and
calibration status are also indicated by this output.
The factory default for full-scale 5 LEL-meters output is
20 mA. MODBUS interfaces also have the ability to cali-
brate the 4 mA and 20 mA levels.
FAULT INDICATION
Faults and status conditions are indicated using the 4-
20 mA analog signal output. Refer to Table 3.
Signaling modes include two predefined and one user
defined mode. PIR9400 mode (default) provides com-
patibility with the DEC R8471J Gas Controller. OPGD-
Rx mode is available as well as a user defined mode for
third party compatibility.
495-85561.1
Default Options
Gas Type Methane Methane, Ethane,
Propane, Butane
Measurement Range 0-5 0-2, 0-5
Low Alarm Threshold 1 1 to 3
High Alarm Threshold 2 1 to 3
Beam Block Delay 60 Seconds 3600 Seconds
Fault Mode PIR9400 Eclipse, PIR
Table 2—Factory Default Settings
Status 4-20 mA Level (±0.1)
PIR9400 OPGD-Rx
Normal Gas: –0.5 to 6 LEL•M 2.4 to 23.3
Warmup 0
Zero Calibration 2.2
Calibration Fault 1.6
Beam Block 1.0
Back-up Lamp Active* 2.4
Calibrate Active at Startup 0.6
EE Error 1.2
Ref. ADC Saturated 0.2
Active ADC Saturated 0.4
24 VDC Fault 0.8
Zero Drift 2.4
Flash CRC Error 1.2
RAM Error 1.2
Table 3—Detector Status Conditions Indicated by Current Level
*Device is still functional. Gas overrides this indication.

SPECIFICATIONS
INPUT VOLTAGE (Both Modules)—
24 Vdc nominal. Operating range is 18 to 30 Vdc.
Ripple cannot exceed 0.5 volts P-P.
POWER CONSUMPTION (Per Module)—
Transmitter
6.0 watts nominal @ 24 Vdc, 6.5 watts @ 30 Vdc.
12.2 watts peak @ 24 Vdc, 19.6 watts peak @ 30 Vdc.
Receiver Without Relays
6.0 watts nominal @ 24 Vdc, 6.8 watts @ 30 Vdc.
12.2 watts peak @ 24 Vdc, 20.5 watts peak @ 30 Vdc.
TRANSMITTER LAMPS
Two xenon flashlamps, field-replaceable module.
WARMUP TIME—
1 minute for transmitter. 30 seconds for receiver from
power-up when correctly aligned.
CURRENT OUTPUT—
Linear 4 to 20 mA (current source/sink, isolated/non-iso-
lated) rated at 600 ohms maximum loop resistance @ 24
Vdc operating voltage.
VISUAL STATUS INDICATOR—
Tri-color LED:
Red = gas alarm
Green = power on / OK
Yellow = fault / back-up lamp mode.
ALARM SETPOINT RANGE—
Low Alarm: 1 to 3 LEL-meters (default = 1)
High Alarm: 1 to 3 LEL-meters (default = 2).
Alarm setpoint is programmable using HART and MOD-
BUS communications.
DETECTION RANGE—
20 to 60 meters; 10 to 20 meters with accessory.
CALIBRATION—
OPECL systems are span calibrated for methane at the
factory.
Zero calibration is accomplished in the field by one of
three methods:
– On-board magnetic reed switch
– MODBUS communication
– HART communication.
Span calibration can be adjusted using HART or MOD-
BUS communication.
Refer to the “Calibration” section of this manual for
details.
RESPONSE TIME—
T90: <5 seconds.
TEMPERATURE RANGE—
Operating: –20°C to +60°C (–4°F to +140°F).
Storage: –55°C to +85°C (–67°F to +185°F).
HUMIDITY—
5 to 99% relative humidity; designed for outdoor appli-
cations.
OPERATING PRESSURE—
91.5 - 105.5 kPA non-compensated.
MEASUREMENT RANGE—
0-5 LEL-meters.
INTERFERENCE RESISTANCE—
Immune to sun and flare radiation, up to 750 W/m2≥3°
to optical axis and common contaminants.
SELF-DIAGNOSTIC TEST—
Fail-Safe operation ensured by performing all critical
tests once per second.
MODULE HOUSING MATERIAL—
CF8M stainless steel (castable 316 equivalent).
CONDUIT ENTRY OPTIONS—
Two entries, 3/4 inch NPT or 25 mm.
HART COMMUNICATION PORT—
Intrinsically safe port on receiver to connect HART
devices.
OPTICS PROTECTION—
Stainless steel brow provides a degree of protection
against windblown dirt and rain. Heated optics mitigate
against ice and dew formation. Heater can be turned
off for indoor applications or reduced power.
WIRING—
Field wiring screw terminals are UL/CSA rated for up to
14 AWG wire, and are DIN/VDE rated for 2.5 mm2wire.
Screw terminal required torque range is 3.5–4.4 in.-lbs.
(0.4-0.5 N·m). Transmitter requires power only.
Receiver can be wired using 3 or 4 wires.
595-85561.1

CERTIFICATION—
CSA: Class I, Div. 1, Groups C & D (T4).
Class I, Div. 2, Groups A, B, C & D (T4).
DEMKO: EEx d e ib IIC, T5.
ATEX: 135898X
EN 50014: 1997 E, A1 & A2.
EN 50018: 2000 E.
EN 50019: 2000 E.
EN 50020: 2002 E.
On-board HART port:
EEx ia IIC T6.
Maximum separation distance between
receiver and communicator is 610 meters.
INGRESS PROTECTION—
IP67.
DIMENSIONS—
Module
Length: 11.5 inches (29 cm).
Diameter: 3.5 inches (9 cm) nominal.
4.5 inches (11 cm) maximum.
Mounting Plate
Height: 11.5 inches (29 cm)
Width: 6 inches (15 cm).
Designed to attach to a 4 inch nominal diameter pipe.
Refer to Figure 2 for mounting dimensions.
SHIPPING WEIGHT—
Transmitter with mounting plate: 35 pounds (16 kg).
Receiver with mounting plate: 35 pounds (16 kg).
WARRANTY—
3 year limited warranty from date of manufacture.
695-85561.1
FLEXIBLE CABLE
17
(43) 13.4
(34)
16.5
(42)
B2251
OPTIONAL
SUNSHADE
MOUNTING
POST
FLAT SURFACE MOUNT
13
(33)
15
(38)
6.5
(16.5)
POST MOUNT
SIDE VIEW OF TYPICAL OPECL
Figure 2—Dimensions of OPECL in Inches (cm)

IMPORTANT SAFETY NOTES
CAUTION
The wiring procedures in this manual are intended
to ensure proper functioning of the system under
normal conditions. However, because of the many
variations in wiring codes and regulations, total
compliance to these ordinances cannot be guaran-
teed. Be certain that all wiring complies with the
NEC as well as all local ordinances. If in doubt,
consult the authority having jurisdiction before
wiring the system. Installation must be done by a
properly trained person.
CAUTION
This product has been tested and approved for use
in hazardous areas. However, it must be properly
installed and used only under the conditions speci-
fied within this manual and the specific approval
certificates. Any device modification, improper
installation, or use in a faulty or incomplete config-
uration will render warranty and product certifica-
tions invalid.
CAUTION
The system contains no user serviceable internal
components. Service or repair should never be
attempted by the user. Device repair should be
performed only by the manufacturer or trained ser-
vice personnel.
LIABILITIES
The manufacturer’s warranty for this product is
void, and all liability for proper function of the sys-
tem is irrevocably transferred to the owner or oper-
ator in the event that the device is serviced or
repaired by personnel not employed or authorized
by Detector Electronics Corporation, or if the sys-
tem is used in a manner not conforming to its
intended use.
CAUTION
Observe precautions for handling electrostatic sen-
sitive devices.
NOTE
The Open Path Eclipse is intended for detection of
hydrocarbon vapors only. The device will not
detect hydrogen gas.
INSTALLATION
IDENTIFICATION OF VAPOR(S) TO BE DETECTED
It is necessary to identify the flammable vapor(s) of
interest at the job site in order to determine the proper
calibration gas setting for Open Path Eclipse. In addi-
tion, the physical and fire hazard properties of the
vapor, such as vapor density and flashpoint should be
identified and used to assist in selecting the optimum
detector mounting locations within the area. The detec-
tor must be installed by qualified personnel only, follow-
ing local electrical equipment installation practices.
SYSTEM LOCATION CONSIDERATIONS
The OPECL system is designed for installation in haz-
ardous industrial areas. Each module is normally
installed using a solid vertical steel post or flat surface
mounting adapter to support the weight of the module.
The modules must be strategically located so that the
hydrocarbon vapor(s) to be detected will intersect the
light beam generated by the transmitter module.
Dispersion characteristics and behavior of the vapor
cloud resulting from a gas leak can be difficult to esti-
mate due to the significant number of variables that
exist at different applications. Identification of expected
gas leakage source(s), leak scenario identification, and
onsite leak simulation are the steps generally recom-
mended to provide the most accurate means of identify-
ing optimum system installation locations.
In all cases, the beam path and surrounding area
should be kept free of obstructions that could block the
infrared beam or hinder the free movement of air within
the area. A clear beam path of 20 CM diameter or
greater is recommended. The system is immune to the
effects of exposure to both direct and reflected sunlight.
Avoid installation in areas with obstructions such as
steam vents and plumes, smoke stacks and chimneys,
walkways and personnel areas, splash and sprayed
water, parking, loading, cranes, vehicle-related areas
such as bus stops, road junctions, and vegetation such
as trees, shrubs, etc.
795-85561.1

Det-Tronics Field Service Engineering group routinely
provides jobsite application surveys and analysis for
customers, and their services are highly recommended
if guidance on optimum installation locations is required.
Additional guidance on the positioning of gas detectors
for optimum coverage is contained in BS6959 and other
national codes. Consult these codes of practice when
determining where detectors are to be located.
Consideration of the following system location guide-
lines is also recommended:
LED Visibility
Select a mounting orientation where the Open Path
Eclipse status indication LED is visible to personnel
within the area.
Module Separation Distance
The transmitter and receiver modules must be installed
directly facing each other across the area to be protect-
ed. Physical obstructions in the direct line of sight
between the modules are not permitted. The overall line
of sight distance between the modules must not exceed
a maximum separation distance of 60 meters (198 feet).
The minimum module separation distance is 20 meters
(66 feet), unless special modifications are provided.
System Mounting Elevation
In all cases, the modules should be installed at the
same elevation above grade to ensure that alignment
capability and foul weather performance are not com-
promised. For detection of lighter than air vapors such
as methane, installation of modules at approximately 2
meters above grade minimizes typical beam block con-
ditions due to human activities, while enabling satisfac-
tory detection capability. For detection of heavier than
air vapors, installation of detectors below the expected
leakage source is generally recommended unless nui-
sance beam blocks will occur at an unacceptable rate.
In this case, identification and analysis of application
specific conditions should be completed to determine
the optimum installation elevation.
Sources of Heavy Contamination
Avoid locations where high levels of contaminants will
persistently be blown onto the detector windows.
Potential sources of heavy contamination include gener-
ator / turbine exhausts, flarestacks, drilling equipment,
process vents / chimneys, etc. If sources of heavy con-
tamination cannot be avoided, consider fitting extra
shielding and/or providing good access for routine
cleaning.
Snow and Ice in Ambients Below –20°C
The heated optics on both modules will melt snow or ice
on the windows in ambient temperatures down to
approximately –20°C. Below this temperature, snow or
ice blown onto the window will not be melted until the
ambient temperature rises. If longterm outdoor opera-
tion in very cold climates is intended, extra shielding /
covers are recommended to prevent accumulation of
snow and ice on the windows.
Deluge and Flooding
The modules are rated IP66 and will not be damaged by
occasional deluge or flooding. However, during such
an event, the unit will completely lose it’s IR signal and
will enter the “Beam-Block / Fault” state. In addition,
when the deluge / flooding subsides, there is the possi-
bility that contaminants will be left on the windows.
Install the modules away from areas particularly prone
to deluge or flooding.
Areas Prone to Subsidence and Settling
Avoid installation of the modules in areas where prob-
lems with subsidence, settling or thawing of permafrost
can occur or cause significant movement. If such loca-
tions cannot be avoided, the foundations of the mount-
ing structure should be engineered to minimize any
angular movements.
Areas Prone to Earthquakes
In the event of an earthquake, there is a chance that the
modules will become misaligned with respect to each
other. As long as the modules do not suffer from direct
mechanical impact damage during an earthquake, they
should remain undamaged by such events. After an
earthquake, it is recommended that the system align-
ment be checked. Antivibration mounts are unlikely to
be of any benefit and are not recommended.
Misalignment by Accidental Impact
Locations where there is a significant likelihood of
equipment, personnel or moving objects accidentally
knocking the modules out of alignment should be avoid-
ed where possible. If such locations cannot be avoid-
ed, measures including improved mechanical protec-
tion and warning notices should be considered.
895-85561.1

MODULE MOUNTING RECOMMENDATIONS
After optimum system module mounting locations are
identified, the preferred module mounting configuration
must be selected. Each module must be affixed to a
solid, non-vibrating structure capable of supporting a
minimum of 100 lbs (46 kg), located within the system’s
maximum rated separation distance. Module mounting
options include:
•Avertical post with a nominal outside diameter of 4.5”
(11.43 cm). Acceptable outside diameter range is 4.0
to 5.0 inches. Ensure that each post is capable of
supporting a minimum of 50 lbs (23 kg). See Figure 3.
•For flat surface mounting, the OPECL flat surface
mount adapter is available. Ensure that the flat sur-
face is capable of supporting a minimum of 100 lbs
(46 kg). See Figure 4. For mounting hole pattern,
refer to Figure 5.
In all cases, the maximum movement of the supporting
structure under all anticipated operating conditions
must be no more than ±0.5 degrees. When using a ver-
tical post, the post should be absolutely stable and with-
out vibration. Generally, when the post is set into the
ground, the portion below grade should be set in con-
crete at least 1 meter deep.
When using the flat surface mounting adapter, ensure
that the two vertical mounting surface planes are
aligned sufficiently to enable proper module alignment.
It is possible that some existing flat surfaces may not
allow proper system alignment using the OPECL mount-
ing and alignment harware.
System modules are shipped disassembled from the
mounting hardware. Before proceeding with module
installation, ensure that all required module installation
components are present, including:
2 OPECL modules,
2 module mounting brackets,
2 pan-tilt plates,
4 U-bolts complete with
8 washers and nuts, and
2 plate support collars.
For flat surface mounting, two OPECL flat surface mount
adapters (ordered separately) must be installed prior to
starting the module installation procedure.
995-85561.1
U-BOLT (2)
OPTIONA
L
SUNSHADE
OPECL
MODULE
MODULE
BRACKET
PAN-TILT PLATE
PLATE SUPPORT COLLAR
MOUNTING
POST
A2244
Figure 3—OPECL Gas Detector Mounted to Vertical Post
U-BOLT (2)
MOUNTING PLATE
PLATE SUPPORT COLLAR
FLAT MOUNTING SURFACE
FLAT SURFACE ADAPTER
A2245
Figure 4—OPECL Gas Detector Mounted to Flat Surface
using Flat Surface Adapter

MODULE INSTALLATION PROCEDURE
(Must be Completed for both Transmitter and
Receiver Modules)
1. Install the Plate Support Collar onto the vertical post
at the desired height. Refer to Figure 6. Ensure that
the plate support collars for both modules are
installed at the same distance above grade/floor ele-
vation to ensure ease of optical alignment later.
Tighten the plate support collar nuts and bolts to
adequately support the entire assembly.
2. Install the Mounting Plate on the vertical post using
(2) U-bolts, (4) washers, and (4) nuts. Tighten the
nuts snugly by hand only at this time so that the
plate is adequately supported but may be rotated if
required.
3. Install the OPECL module onto the Mounting Plate.
Tighten snugly to support the weight of the device.
4. Double check to ensure that the module is ade-
quately supported and is ready for electrical wiring.
IMPORTANT
Do not allow any water or other contaminants to
enter the OPECL electrical termination enclosure if
a delay is expected.
24 VDC POWER SUPPLY REQUIREMENTS
Calculate the total gas detection system power con-
sumption rate in watts from cold start-up. Select a
power supply with adequate capability for the calculat-
ed load. Ensure that the selected power supply pro-
vides regulated and filtered 24 Vdc power for the entire
system. If a back-up power system is required, a float-
type battery charging system is recommended. If an
existing source of 24 Vdc power is being utilized, verify
that system requirements are met.
WIRING CABLE REQUIREMENTS
Always use proper cabling type and diameter for input
power as well as output signal wiring. 14 to 18 AWG
shielded stranded copper wire is recommended.
Always install a properly sized master power fuse or
breaker on the system power circuit.
NOTE
The use of shielded cable in conduit or shielded
armored cable is recommended for optimum
RFI/EMI protection. In applications where the
wiring is installed in conduit, dedicated conduit is
recommended. Avoid low frequency, high voltage,
and non-signaling conductors to prevent nuisance
EMI problems.
CAUTION
The use of proper conduit installation techniques,
breathers, glands, and seals is required to prevent
water ingress and/or maintain the explosion-proof
rating.
10 95-85561.1
MOUNING PLATE
SUPPORT COLLA
R
MOUNTING POS
T
U-BOL
T
U-BOL
T
A2212
Figure 6—OPECL Detector Attached to Mounting Post
12"
(30.5 CM)
5.25"
(13.3 CM)
A2246
Figure 5—Hole Pattern for Flat Surface Mount Adapter

POWER WIRING SIZE AND MAXIMUM LENGTH
1. The OPECL detector must receive 18 Vdc minimum
to operate properly. 24 Vdc minimum is recom-
mended.
2. Always determine voltage drops that will occur to
ensure that 24 Vdc is delivered to the OPECL.
3. Normally, nothing smaller than 18 AWG (0.75 mm2)
is recommended by Det-Tronics for OPECL power
cabling.
Wire size requirements are dependent upon power sup-
ply voltage and wire length.
The maximum distance between the OPECL detector
and its power supply is determined by the maximum
allowable voltage drop for the power wiring loop. If the
voltage drop is exceeded, the device will not operate.
To determine the maximum power loop voltage drop,
subtract the minimum operating voltage for the device
(18 Vdc) from the minimum output voltage of the power
supply.
To determine the actual maximum wire length:
1. Divide the maximum allowable voltage drop by the
maximum current draw of the OPECL (0.64 A),
2. Divide by the resistance of the wire (ohms/foot value
available in wire manufacturer’s specification data
sheet),
3. Divide by 2.
For example: Consider an installation using 18 AWG
wiring with a power supply providing 24 Vdc.
Power supply voltage = 24 Vdc,
OPECL minimum operating voltage = 18 Vdc
24 – 18 = 6 Vdc
Maximum Voltage Drop = 6
Maximum Current = 0.64 A
Wire Resistance in Ohms/Foot = 0.006523
6 ÷ 0.64 ÷ 0.006523 ÷ 2 = 718 feet
WIRING PROCEDURE
For systems using conduit, modules must be wired
using a short piece of suitable flexible conduit to allow
optical alignment of the modules. Ensure that all cables
are terminated properly. Open Path Eclipse screw ter-
minal torque range is 3.5–4.4 in.-lbs. (0.4–0.5 N·m).
Cable shield, if used, should be properly terminated. If
not terminated, clip the shield wire off short and insulate
it within the detector housing to prevent the shield wire
from accidentally contacting the detector housing or
any other wire.
Figure 7 shows the wiring terminal strip located inside
the detector’s integral junction box. Figure 8 shows the
wiring terminal configuration for the OPECL receiver.
Figure 9 shows the wiring terminal configuration for the
OPECL transmitter. (The transmitter requires only oper-
ating power.) Figures 10 through 13 show the 4 to 20
mA output of the OPECL receiver in various wiring
schemes. Figure 14 shows the OPECL wired to a Model
R8471J Controller.
NOTE
The OPECL housing must be electrically connect-
ed to earth ground. A dedicated earth ground lug
is provided for this purpose.
NOTE
For proper HART communication, it is required
that an analog signal loop resistance of 250 to 500
ohms be present at the receiver analog output ter-
minals. See Figure 15 for benchtop test wiring.
11 95-85561.1
EARTH GND LUG
A2084
Figure 7—Terminal Strip Located Inside Wiring Compartment

12 95-85561.1
24 VDC
+–
+
–
–24 VDC
–24 VDC
+24 VDC
+24 VDC
CALIBRATE
+ 4-20 MA
– 4-20 MA
RS-485 A
RS-485 B
RELAY POWER
FAULT
LOW ALARM
HIGH ALARM
1
2
3
4
5
6
7
8
9
10
11
12
13
NO USER CONNECTION
4 to 20 MA
B2050
*TOTAL LOOP RESISTANCE = 250 OHMS MINIMUM, 600 OHMS MAXIMUM.
*
24 VDC
+–
+–
–24 VDC
–24 VDC
+24 VDC
+24 VDC
CALIBRATE
+ 4-20 MA
– 4-20 MA
RS-485 A
RS-485 B
RELAY POWER
FAULT
LOW ALARM
HIGH ALARM
1
2
3
4
5
6
7
8
9
10
11
12
13
NO USER CONNECTION
4 to 20 MA
B2051
*TOTAL LOOP RESISTANCE = 250 OHMS MINIMUM, 600 OHMS MAXIMUM.
*
Figure 11—Detector Wired for Non-Isolated 4 to 20 ma Current
Output (Sourcing)
Figure 10—Detector Wired for Non-Isolated 4 to 20 ma Current
Output (Sinking)
–24 VDC
–24 VDC
+24 VDC
+24 VDC
CALIBRATE
+ 4-20 MA
– 4-20 MA
RS-485 A
RS-485 B
NO USER CONNECTION
1
2
3
4
5
6
7
8
9
10
11
12
13
A219
6
Figure 8—Receiver Wiring Terminal Identification
–24 VDC
+24 VDC
NO USER CONNECTION
1
2
3
4
5
6
7
8
9
10
11
12
13
A2197
Figure 9—Transmitter Wiring Terminal Identification

13 95-85561.1
24 VDC
+–
24 VDC
+–
–24 VDC
–24 VDC
+24 VDC
+24 VDC
CALIBRATE
+ 4-20 MA
– 4-20 MA
RS-485 A
RS-485 B
RELAY POWER
FAULT
LOW ALARM
HIGH ALARM
1
2
3
4
5
6
7
8
9
10
11
12
13
NO USER CONNECTION
+
–
4 to 20 MA
B2052
*TOTAL LOOP RESISTANCE = 250 OHMS MINIMUM, 600 OHMS MAXIMUM.
*
24 VDC
+–
24 VDC
+–
–24 VDC
–24 VDC
+24 VDC
+24 VDC
CALIBRATE
+ 4-20 MA
– 4-20 MA
RS-485 A
RS-485 B
RELAY POWER
FAULT
LOW ALARM
HIGH ALARM
1
2
3
4
5
6
7
8
9
10
11
12
13
NO USER CONNECTION
+–
4 to 20 MA
B2053
*TOTAL LOOP RESISTANCE = 250 OHMS MINIMUM, 600 OHMS MAXIMUM.
*
Figure 13—Detector Wired for Isolated 4 to 20 ma Current Output
(Sourcing)
Figure 12—Detector Wired for Isolated 4 to 20 ma Current Output
(Sinking)
CURRENT OUTPUT
CHASSIS GROUND
POWER
SENSOR
EXTERNAL RESET
HIGH ALARM
HIGH ALARM / OC
AUX. ALARM
AUX. ALARM / OC
LOW ALARM
LOW ALARM / OC
FAULT
FAULT / OC
1
3
4
5
6
7
8
9
10
11
12
13
14
15
16
–
+
+
–
+
–
18 TO 32
VDC
POWER
SIGNAL
2
OC = OPEN COLLECTOR OUTPUT
(BASE MODEL ONLY)
A2247
–24 VDC
+24 VDC
– 4-20 MA
1
2
3
4
5
6
7
8
9
10
11
12
13
R8471J CONTROLLER
MODEL OPECL
GAS DETECTOR
+ 4-20 MA
24 VDC
–24 VDC
+24 VDC
+
–
2
1
NOTES: 1INTERNAL JUMPER REQUIRED
FOR NON-ISOLATED CURRENT
OUTPUT (SINGLE POWER
SUPPLY).
2250 OHM RESISTOR REQUIRED.
Figure 14— Model OPECL Receiver Wired to a Model
R8471J Controller
–24 VDC
–24 VDC
+24 VDC
+24 VDC
CALIBRATE
+ 4-20 MA
– 4-20 MA
RS-485 A
RS-485 B
RELAY POWER
FAULT
LOW ALARM
HIGH ALARM
NO USER
CONNECTION
1
2
3
4
5
6
7
8
9
10
11
12
13
A2203
24 VDC
+
–
250 TO 500 OHMS
Figure 15—Wiring the Model OPECL for Benchtop
Testing/Programming Using HART Protocol

STARTUP
When the OPECL is installed and wired as described in
the “Installation” section, it is ready for commissioning.
If the application requires that specific changes be
made to the factory settings, HART communication will
be required.
NOTE
Ensure that alarm devices are bypassed during
commissioning.
ALIGNMENT
OVERVIEW
The OPECL modules must be properly aligned before
normal operation can be attained. There are two align-
ment procedure options:
1. Basic Alignment Procedure. This option requires
the OPECL alignment kit, but does not require a
handheld HART communicator.
2. Full Alignment Procedure. This option requires the
OPECL alignment kit and a handheld HART commu-
nicator with the OPECL device descriptor (DD) soft-
ware menu. The full alignment procedure is recom-
mended whenever maximum optical signal strength
is required at the receiver.
BASIC ALIGNMENT PROCEDURE
Equipment Required
1. Properly installed and powered OPECL system
(transmitter and receiver). Easy access to both
modules is highly recommended.
2. OPECL Alignment Kit (PN 007726-001). Kit includes
a battery powered laser, a laser holder, alignment
target and target holder.
3. Alignment Adjuster Kit (PN 007745-001). Optional
kit includes a battery powered laser, a laser holder,
alignment target and target holder, and removable
vertical and horizontal adjusters. Recommended for
maximum ease in achieving proper alignment. See
Figure 16.
4. Calibration magnet.
Ensure that system power is turned off and metal visors
are slid to the rear to prevent damage, then complete
the following steps:
1. Ensure that both system modules are properly
installed on their respective mounting plate/post
assemblies at a separation distance within the spec-
ified range, and are correctly wired.
14 95-85561.1
MOUNTING PLATE SUPPORT COLLA
R
LASER MOUNTED IN LASER HOLDER
DETECTOR MOUNTING PLAT
E
VERTICAL ALIGNMENT TOOL (2
)
HORIZONTAL ALIGNMENT TOO
L
4" DIAMETER MOUNTING POST
WEATHER PROTECTION BONNET
REMOVED FOR CLARITY
A2199
VERTICAL ADJUSTMENT PLATE
Figure 16—OPECL Detector with Optional Alignment Tools and Laser Aimer Installed

2. Ensure that both system modules are mounted at
approximately the same height above grade level,
and that each module is roughly aligned to directly
face the other module’s lens surface.
3. Ensure that the four nuts on each module’s mounting
U-bolts are sufficiently tightened to properly support
the module, yet allow horizontal (left/right) adjust-
ment of the plate/module by hand without binding.
4. Ensure that the mounting bracket nuts are sufficient-
ly tightened to properly support the module’s
up/down angle without deflection, yet allow the mod-
ule to be vertically adjusted by hand without binding.
It is recommended to tighten the lower bracket nut
slightly more than the upper bracket nut.
5. Attach the laser aimer holder to the front face of the
Transmitter by threading the holder’s two captive
screws into the respective threaded holes on the
Transmitter faceplate. Insert the battery-powered
laser into the holder. Do not turn on the laser yet.
6. Attach the alignment target holder to the front face of
the Receiver. Insert the alignment target into the
holder.
7. Turn on the laser aimer and slowly move the trans-
mitter module left or right as required until the laser
spot hits the the alignment target as close as possi-
ble to dead center. Tighten the U-bolt nuts so that
no left/right movement will occur.
8. Slowly move the transmitter module up or down as
required until the laser spot hits the alignment target
as close as possible to dead center. Tighten the
module mounting bracket nuts so that no up/down
movement will occur. As this point, the laser spot
should be aimed dead center on the alignment tar-
get. Turn the laser off.
9. Exchange the laser and aiming target locations by
removing the laser from the laser holder and insert-
ing it into the Receiver’s target holder. Relocate the
alignment target into the Transmitter’s holder.
10. Repeat steps 7 and 8 with the laser installed on the
Receiver module.
11. Remove the laser, laser holder, target, and target
holder from both modules.
12. Bypass all external gas alarm devices that are con-
nected to the receiver outputs, and apply 24 Vdc
power to the modules.
13. Upon completion of warm-up mode (approximately 2
minutes), the receiver should display a green LED,
indicating that the system is in normal operating
mode. If the green LED is not displayed, confirm
that the transmitter is generating a visible light flash,
that the receiver is powered up, that the modules are
within the specified mounting distance, and then
repeat steps 1 to 10 above.
NOTE
If monitoring the 4-20 mA signal output, do not be
alarmed if the signal is greater than 4.0 mA. This
is common and will be corrected by performing a
zero calibration.
14. Perform a zero calibration using the calibration mag-
net. Any faults or alarms that may be present as a
result of the alignment process will be cleared.
15. When the zero calibration is successfully completed,
Basic Alignment is completed.
NOTE
If Full Alignment will be performed, stop here and
go directly to Step 1 in the “Full Alignment
Procedure”.
16. Confirm proper operation by blocking the light beam
with a solid object such as cardboard until a beam
block fault is generated (default setting is 60 sec-
onds).
17. Confirm proper operation by installing the optical
test film into the light beam and checking for a low
gas alarm condition. The alarm condition should
clear when the film is removed from the beam.
15 95-85561.1

16 95-85561.1
FULL ALIGNMENT PROCEDURE
Completion of the Full Alignment procedure is recom-
mended when maximum optical signal strength is
required at the receiver module — typically in outdoor
applications and areas with high levels of optical con-
tamination or fog. It is necessary to complete the Basic
Alignment procedure before starting the Full Alignment
procedure.
In addition to the equipment needed for Basic
Alignment, Full Alignment requires the use of a hand-
held HART communication device such as the intrinsi-
cally-safe Emerson Model 375 HART communicator.
The use of Alignment Kit p/n 007745-001 is also highly
recommended to enable precision control of the vertical
and horizontal alignment orientation of the OPECL
Receiver module. The OPECL transmitter is not adjust-
ed in the Full Alignment procedure.
HART Communicator Notes
•For hazardous areas, ensure that the HART communi-
cator is certified for use in classified areas.
•The HART communicator must include the Device
Descriptor (DD) software menu for OPECL. The use
of a HART communicator without the proper DD’s may
establish generic mode HART communication, but will
not allow Full Alignment to be completed. Refer to the
HART Appendix for additional information.
•Aminimum level of understanding with regard to the
operation and navigation of the HART communicator
is required to complete the Full Alignment procedure.
Please refer to the appropriate HART communicator
instruction manual for basic operating instructions if
needed. Additional information on the use of the
HART communicator is provided in the HART
Appendix in this document.
•For proper HART communication to occur, a 250-500
ohm resistive load is required in the 4-20 mA signal
loop (as shown in Figures 10 to 13).
After completion of Step 15 in the Basic Alignment pro-
cedure, begin the Full Alignment procedure.
1. Install the horizontal and vertical alignment tools
from the Alignment Kit as shown in Figure 16.
Ensure that the horizontal alignment tool clamp is
tightened on the mounting post.
2. Connect the handheld HART communicator to the
Receiver module’s onboard HART communication
port.
3. Turn on the HART communicator and inspect for
OPECL device recognition. When HART communi-
cation is established, the OPECL Receiver Root
menu will be displayed on the communicator display
screen.
4. From the Root Menu, select the Test Menu (selection
5).
5. From the Test Menu, select the Alignment Menu
(selection 6).
6. The Alignment Menu will display the following
screen:
7. If the value displayed to the right of “Reference” is
greater than 900, stop Full Alignment. Too much
optical energy is present at the receiver, and the
separation distance must be increased to a mini-
mum of 20 meters. If the reading is below 900, pro-
ceed to step 8.
8. From the Alignment Menu, select Enable Alignment
(selection 4). This places the receiver in Alignment
mode, resulting in:
A. an Amber LED on the receiver.
B. default analog signal of 1 milliampere, causing a
fault condition to be displayed on the Detronics
R8471J gas controller.
C. no signal levels above the default signal level or
alternative level as programmed.
NOTE
When the Alignment mode is enabled, the HART
communicator occassionally displays a message
stating “Non-zero status codes found. Ignore the
next 50 occurences?” When this occurs, enter
“Yes”, and continue the Full Alignment procedure.
Alignment Menu
1) Quad X XXX
2) Quad Y XXX
3) Reference XXX
4) Enable Alignment
5) Disable Alignment
Numerical value indicating
Horizontal Axis Signal Strength
Numerical value indicating
Vertical Axis Signal Strength
Numerical value must be
below value 900.

9. Numerical values are displayed on the right side of
the Alignment Menu screen to indicate the relative
optical signal strength for each axis. The numerical
value displayed to the right of “Quad X” indicates
horizontal (left/right) signal strength. The numerical
value displayed to the right of “Quad Y” indicates
vertical (up/down) signal strength. The optimum
value is zero (0.00). It is normal for a fair amount of
signal instability to be present; therefore it is recom-
mended to monitor the value for a minimum of 15-30
seconds to determine the average reading. If the
readings average zero, no adjustments are neces-
sary. Proceed to step 12.
10. If the Quad X reading does not average zero, slowly
adjust the horizontal adjustment knobs as necessary
to achieve an average reading of zero at Quad X.
Make alignment adjustments in very small incre-
ments, and always monitor the value for a minimum
of 15-30 seconds after making any adjustment to
determine the relative average indication change.
Generally, only slight adjustments are required to
achieve maximum signal strength.
NOTE
Do not attempt to tighten any adjustment knob if
the opposing knob is tightened hard against the
mounting plate hardware. It is necessary to slight-
ly loosen the opposing adjuster in all cases before
attempting to tighten an adjuster.
11. If the Quad Y reading does not average zero, slowly
adjust the vertical adjustment knobs as necessary to
achieve an average reading of zero at Quad Y.
Make alignment adjustments in very small incre-
ments, and always monitor the value for a minimum
of 15-30 seconds after making any adjustment to
determine the relative average indication change.
Generally, only slight adjustments are required to
achieve maximum signal strength. Do not attempt to
tighten any adjustment knob if the opposing knob is
tightened hard against the mounting plate hardware.
It is necessary to slightly loosen the opposing
adjuster in all cases before attempting to tighten an
adjuster.
12. When an average numerical indication of “0” (zero)
is displayed for the Quad X and Quad Y values,
slowly hand-tighten the adjustment knobs on each
axis simultaneously. When the knobs are tight, the
OPECL mounting plate should be firmly held in
place by the adjusters.
13. Tighten all Mounting Plate U-bolt nuts and vertical
adjustment bracket bolts. Double check the Quad X
& Y values to ensure that there has been no module
movement.
14. Remove the Alignment Kit adjustment tools.
15. From the Alignment Menu, select Disable Alignment
(selection 5). This places the receiver in normal
mode, generating a green LED indication and a live
4 mA signal level.
16. Perform a zero calibration.
17. Confirm proper operation by blocking the light beam
with a solid object such as cardboard until a beam
block fault is generated (default time delay is 60
seconds).
18. Bypass all system alarms and confirm proper opera-
tion by placing the optical test film into the light
beam and inspecting for a low gas alarm condition.
The alarm condition should clear when the film is
removed from the beam.
19. The system is fully aligned.
17 95-85561.1

CALIBRATION
CALIBRATION OVERVIEW
Although routine calibration of the Open Path Eclipse is
normally not required, the device supports non-intrusive
field zero calibration capability. Span calibration is not
required.
Zero Calibration
Zero Calibration is a one-step process consisting of
clean air (zero) condition adjustment only, which is per-
formed automatically by the device. This procedure
adjusts the "clean air" signal output only, and is normally
used if the 4 milliampere signal level has drifted. The
cause of drift is typically due to the presence of back-
ground gas during calibration. Ensure that the optical
path is clear of hydrocarbons prior to calibration initia-
tion to ensure an accurate zero (clean air) condition.
IMPORTANT CALIBRATION NOTES
NOTE
Ensure that the detector has been operating for at
least two hours before calibrating.
NOTE
Always ensure that the OPECL optics are totally
free of all hydrocarbons before initiating calibration.
CALIBRATION INITIATION
Calibration may be initiated by any of the following
means:
•The onboard magnetic calibration switch
•Digital communication via MODBUS communication
(consult factory for details)
•Remote calibration line.
Calibration Using Magnetic Switch
The Open Path Eclipse provides an onboard magnetic
calibration/reset switch for non-intrusive calibration
capability. The magnetic switch is actuated by holding
a calibration magnet at the specified located on the
device bulkhead. See Figure 1 for switch location. An
onboard tri-color LED provides status indication during
calibration.
For zero calibration, the magnetic switch must be actu-
ated for 2 seconds to initiate calibration (signaled by a
solid red LED). Upon initiation, the OPECL automatical-
ly performs the zero calibration adjustment, and then
signals with a green LED when this operation is com-
plete.
Digital Communication Calibration
MODBUS communication may be utilized to initiate
OPECL calibration (consult factory).
DETAILED CALIBRATION PROCEDURE USING
MAGNETIC SWITCH
Zero Calibration
1. Apply magnet for 2 seconds minimum to initiate cali-
bration.
A. The onboard LED turns to steady red.
B. The current output decreases to 1 mA.
2. When zero calibration is complete:
A. The onboard LED changes from steady red to
steady green.
B. Calibration is complete and current output
returns to 4 mA.
18 95-85561.1

MAINTENANCE
ROUTINE INSPECTION
The Open Path Eclipse detector should be inspected
periodically to ensure that external obstructions such as
plastic bags, mud, snow, or other materials do not block
the path and thereby impair the performance of the
device.
OPTICS CLEANING
Cleaning of the OPECL optical surfaces is normally
required only if an optical fault is indicated.
Thoroughly douse both window surfaces using a liberal
amount of isopropyl alcohol to clear away contaminant
particles. Repeat the alcohol flush to remove any
remaining contaminants.
PROTECTIVE CAPS AND COVERS
Ensure that the HART Communication Port cover and
the wiring compartment cover are installed and fully
engaged.
TROUBLESHOOTING
A Fault status is indicated by a yellow LED and also by
the 4 to 20 mA output. Refer to Table 4 for assistance in
correcting malfunctions with the Open Path Eclipse
Detector.
19 95-85561.1
Fault Condition Corrective Action
Low 24 volts 24 vdc operating voltage is out of range. Verify proper wiring to the detector and cor-
rect voltage output from the power source. Power supply faults are self-clearing when
the condition is corrected. If the fault does not clear, consult the factory.
Dirty Optics Perform cleaning procedure, then recalibrate as required. (Refer to “Maintenance” for
details.)
Calibration Fault If the calibration process is allowed to time-out, the fault is set and can only be reset
with a successful calibration.
Negative Signal Output This fault is indicated when the signal output drops below 0.5 LEL•M. Normally detec-
tion capability is not compromised in this condition. The device was probably zero cali-
brated with background gas present. If the condition persists, purge with clean air and
repeat the zero calibration.
Calibration line active at start-up The only way to clear this fault is to correct the wiring and reapply power. Be sure that
the calibration line is not shorted and that the calibration switch is open. If the fault
does not clear, consult the factory.
EE Error If power is interrupted while the unit is updating its internal data logs, an EE Error may
occur. Cycling power will correct this fault.
Other Faults Consult the factory.
Table 4—Troubleshooting Guide

DEVICE REPAIR AND RETURN
The Open Path Eclipse IR Hydrocarbon Gas Detector is
not designed to be repaired in the field. If a problem
should develop, first carefully check for proper wiring,
programming and calibration. If it is determined that the
problem is caused by an electronic failure, the device
must be returned to the factory for repair.
Prior to returning devices or components, contact the
nearest local Detector Electronics office so that a
Service Order number can be assigned. A written
statement describing the malfunction must accompany
the returned device or component to expedite finding
the cause of the failure.
Return all equipment transportation prepaid to the facto-
ry in Minneapolis.
ORDERING INFORMATION
OPEN PATH ECLIPSE DETECTOR
When ordering, please specify:
3/4 inch threads, 0 to 5 LEL-meters, 4 to 20 mA or
M25 threads, 0 to 5 LEL-meters, 4 to 20 mA.
ALIGNMENT EQUIPMENT
Part Number Description
007726-001 Open path alignment kit consists of a
diode laser aiming apparatus and a
precision aligned laser holder.
007745-001 Optional alignment tool kit consists of
Rotational Pivot Lock (horizontal), Top
Pivot Lock (vertical), and Bottom Pivot
Lock (vertical).
SPARE PARTS
Calibration Magnet 102740-002
Silicone Free Grease 005003-001
O-Ring, 3.75” i.d., for wiring
compartment cover 107427-040
O-Ring, 3.25” i.d., for front
flange (internal) 107427-052
ASSISTANCE
For assistance in ordering a system to meet the needs
of a specific application, contact:
Detector Electronics Corporation
6901 West 110th Street
Minneapolis, Minnesota 55438 USA
Operator: [phone] or (800) 765-FIRE
Customer Service: [phone]
Fax: [phone]
Web site: www.detronics.com
E-mail: [email protected]
20 95-85561.1