MSA FL500 UV/IR User manual

Operating Manual
FL500 UV/IR, FL500-H2 Flame Detector
Order No.: 10193213/07
Print Spec: 10000005389 (EO)
CR: 800000051120
MSAsafety.com

© MSA 2022. All rights reserved
WARNING!
Read this manual carefully before using or maintaining the device. The device will perform as designed only if it is used and
maintained in accordance with the manufacturer's instructions. Otherwise, it could fail to perform as designed, and persons
who rely on this device could sustain serious injury or death.
The warranties made by MSA with respect to the product are voided if the product is not installed and used in accordance with
the instructions in this manual. Please protect yourself and your employees by following the instructions.
Please read and observe the WARNINGS and CAUTIONS inside. For additional information relative to use or repair, call
1-800-MSA-2222 during regular working hours.
For countries of Russian Federation, Republic of Kazakhstan and Republic of Belarus, the gas detector will be delivered with a
passport document that includes valid approval information. On the CD with manual instruction attached to the gas detector
the user will find the documents "Type Description" and "Test Method" - appendixes to Pattern Approval Certificate of
Measuring instrument, valid in the countries of use.
The Declaration of Conformity can be found under the following link: https://MSAsafety.com/DoC.
MSA is a registered trademark of MSA Technology, LLC in the US, Europe and other Countries. For all other trademarks visit
https://us.msasafety.com/Trademarks.
General Monitors
16782 Von Karman Avenue, Unit 14
Irvine, CA 92606
1-949-581-4464
For your local MSA contacts, please go to our website www.MSAsafety.com

Contents
1 Safety Regulations 4
1.1 Correct Use 4
1.2 Liability Information 5
1.3 Warranty 5
2 Description 6
2.1 Overview 6
2.2 Continuous Optical Path Monitoring (COPM) 7
2.3 LED Operation Mode Definitions 7
3 Installation 8
3.1 Required Tools 8
3.2 Locations 9
3.3 Mounting 16
3.4 Wiring 18
3.5 Terminal Connections 19
3.6 Cable Lengths 22
3.7 Power Supply 23
3.8 Chassis Ground 23
3.9 Fire Cards or Panels 23
3.10 Cable Termination in a Nonhazardous Area 23
4 Operation 24
4.1 Start-Up 24
4.2 Changing Device Settings 24
4.3 Sensitivity Check 26
5 Maintenance 27
5.1 Regular Maintenance 27
5.2 Cleaning the Optical Window and Reflectors 28
5.3 Annual Maintenance 28
6 Storage 28
7 Troubleshooting 29
7.1 Troubleshooting Table 29
7.2 Returning the Device for Repairs 30
7.3 Removing the Device from Service Permanently 30
7.4 References and Other Sources of Help 30
8 Specifications 31
8.1 System Specifications 31
8.2 Mechanical Specifications 32
8.3 Electrical Specifications 32
8.4 Environmental Specifications 33
9 Approvals 34
10 Ordering Information 34
FL500 UV/IR, FL500-H2 Flame Detector 3
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1 Safety Regulations
1.1 Correct Use
WARNING!
• Do NOT install or operate the device until you read and understand the instructions in this manual. Only qualified personnel
are approved to operate and do maintenance on the device.
• Do NOT remove the cover from the device when the device is in operation or in an explosive atmosphere.
• Install a conduit seal within 18 in. (46 cm) of the device enclosure.
• Repair or alteration of the device beyond the scope of the maintenance instructions in this manual or by anyone other than
General Monitors or General Monitors-approved service personnel can cause incorrect operation of the device and put
persons who use this device for their safety at risk of serious injury or death.
• An approved electrician must do electrical wiring.
• All wiring must satisfy the requirements of the applicable NationalElectricalCode (NEC), CanadianElectricalCode
(CEC), and local electrical safety codes.
• Make sure that field connections to the FL500 are applicable for the location and obey the wiring requirements of the NEC,
CEC, and local electrical safety codes.
• Do not install or operate a device that is damaged.
• Install the device in a location away from conditions (such as high-pressure steam) where electrostatic charge can collect
on nonconducting surfaces. This equipment uses an external nonmetallic coating. If extreme levels of electrostatic charge
collect, ignition can occur.
• Make sure that there is no physical blockage from permanent objects such as structures and equipment or temporary
objects such as personnel and vehicles in the sensor's field of view. Ifthere is physical blockage in the sensor's field of
view, the device cannot accurately monitor the area for flame.
• Make sure that there is no ice, dirt, or debris on the optical window. Blockage of the optical window can result in a Fault
condition.
• During a Fault condition, the device does not monitor the area for flame.
• Keep the device safe from vibration and mechanical shock, which can cause damage.
• Do NOT connect or disconnect equipment when power is supplied to the device. Doing so can result in serious damage to
the equipment. The warranty does not apply to equipment that is damaged in this way.
• The device has components that can be damaged by electrostatic discharge (ESD). When you do work with the device
wiring, be careful to touch only the connection points. The warranty does not supply coverage for components that are
damaged by ESD.
• Use ONLY a damp cloth to clean the device. Otherwise, electrical shock or ignition from ESD can occur.
Failure to obey these warnings can result in serious injury or death.
For dimensional information about the flameproof joints, contact General Monitors.
Specific Conditions of Safe Use
• Potential electrostatic charging hazard; use only a damp cloth for cleaning.
• Contact General Monitors if dimensional information of flameproof joints is needed.
• Field connections to the FL500 shall be appropriately certified for the location and installed in accordance with wiring
method requirements of the local electrical code as applicable.
4 FL500 UV/IR, FL500-H2 Flame Detector
1 Safety Regulations US

1.2 Liability Information
General Monitors accepts no liability in cases where the product has been used inappropriately or not as intended.
The selection and use of this product must be under the direction of a qualified safety professional who has carefully evaluated
the specific hazards of the jobsite where it will be used and who is completely familiar with the product and its limitations. The
selection and use of this product and its incorporation into the safety scheme of the jobsite is the exclusive responsibility of the
employer.
Changes and modifications not expressly approved by the manufacturer will void the user's authority to operate the equipment.
1.3 Warranty
1.3.1 Limited Express Warranty
General Monitors warrants the product to be free from mechanical defects and faulty workmanship for a period of two (2) years
from the date of sale by General Monitors, provided that the product is maintained and used in accordance with General
Monitors' instructions and/or recommendations. General Monitors makes no warranty concerning components or accessories
not manufactured by General Monitors, but will pass on to the Purchaser all warranties of manufacturer.
This warranty is valid only if the product is maintained and used in accordance with General Monitors' instructions and/or
recommendations. General Monitors shall be released from all obligations under this warranty in the event that repairs or
modifications are made by persons other than its own or authorized service personnel, or if the warranty claim results from
accident, alteration, misuse, or abuse.
No agent, employee or representative of General Monitors has authority to bind General Monitors to any affirmation,
representation or modification of the warranty concerning the product.
THIS WARRANTY IS STRICTLY LIMITED TO THE TERMS HEREOF AND IN LIEU OF ALL OTHER WARRANTEES,
EXPRESSED, IMPLIED, OR STATUTORY INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
1.3.2 Sole Remedy
It is expressly agreed that Purchaser's sole and exclusive remedy for breach of the above warranty, for any tortious conduct of
General Monitors, or for any other cause of action, shall be the repair or replacement, at General Monitors' option, of any
equipment or parts thereof, which after examination by General Monitors is proven to be defective. Replacement equipment
and/or parts will be provided at no cost to Purchaser, F.O.B. Seller's Plant. Failure of General Monitors to successfully replace
any nonconforming equipment or parts shall not cause the remedy established hereby to fail of its essential purpose.
1.3.3 Exclusion of Consequential Damage
Purchaser specifically understands and agrees that under no circumstances will General Monitors be liable to Purchaser for
economic, special, incidental, or consequential damages or losses of any kind whatsoever, including but not limited to, loss of
anticipated profits and any other loss caused by reason of non-operation of the goods. This exclusion is applicable to claims for
breach of warranty, tortious conduct or any other cause of action against General Monitors.
FL500 UV/IR, FL500-H2 Flame Detector 5
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2 Description
2.1 Overview
The following two models exist:
• FL500 UV/IR
• FL500 H2
The models are not interchangeable.
The FL500 UV/IR is optimized for and to be used for hydrocarbon flame detection, whereas the FL500 H2is optimized for and
to be used for hydrogen flame detection.
The FL500 ultraviolet/infrared (UV/IR) flame detector, referred to hereafter as the "FL500" or "device," uses a UV radiation-
sensitive phototube and an IR detector to sense specific wavelengths in the UVand IR spectral regions. The UV and IR
detectors send signals about changes in the intensity of UV and IR radiation to a microcomputer to activate Alarm Low, Alarm
High, and Fault output. A flicker discrimination circuit in the IR circuitry prevents false alarms caused by lightning, arc-welding,
hot objects, and other sources of radiation. The inherent flickering of a flame supplies the necessary modulation to activate the
IR circuit.
Visible Region
Wavelength
Relative Energy
Ultraviolet Region Infrared Region
Sun’s Radiation
Reaching Earth
185 nm 260 nm
UV Detector’s
Spectral
Sensitivity
IR Detector’s
Spectral
Sensitivity
2.95 μm
(Hydrogen Detector)
4.35 μm
Figure 1 Spectral Response of UV and IR Radiation Detectors
If the device senses only UV radiation (such as arc welding) or only IR radiation (such as a large modulating hot object), an
alarm does not occur. If the device senses both UV and IR radiation in the correct combination and intensity, as set by an
algorithm in the microcomputer, the device identifies a fire and sends the following output:
• 4 - 20 mA signal
• Immediate Alarm Low output
• Time-delayed Alarm High output
• RS-485 Modbus RTU output
• HART communication
The FL500 has the following features:
• Compact unitized design
• Wide field of view
• Continuous optical path monitoring (COPM)
• 4 - 20 mA source or sink, alarm relays, and Modbus RTU RS-485 standard
6 FL500 UV/IR, FL500-H2 Flame Detector
2 Description US

• HART 7 communication
• False alarm prevention
Figure 2 FL500 UV/IR, FL500-H2Flame Detector
The FL500 is compatible with the General Monitors TA402Atripamplifier, FL802controller, and other equipment that accepts
4-20mA output. The device can be connected directly with alarm and suppression devices or switched input modules through
integral relays. If the HART protocol is used with the FL802controller, it is necessary to use the special HART signal (1.25-
20mA).
Because the FL802 controller is not CE marked, it cannot be supplied to the European Union (EU).
2.2 Continuous Optical Path Monitoring (COPM)
COPM does a check of the device's optical path (from the internal UV and IR detectors through an air gap then the optical
window) and related electronic circuitry every 2 minutes. If the optical window is blocked by unwanted objects such as ice,
dirt, or debris for two consecutive checks, the device activates the following Fault output:
• 2.0 mA signal
• Fault relay de-energizes
• Modbus signal
After a COPM Fault occurs, COPM occurs every 30 seconds until the Fault condition is removed. When the Fault condition is
removed, COPM continues every 2 minutes.
Because COPM does a check of the optical path every 2 minutes and two consecutive checks must fail before a
Fault occurs, it can be up to 3 minutes before the device identifies a blockage.
Refer to Section 5.2 Cleaning the Optical Window and Reflectors for maintenance instructions.
2.3 LED Operation Mode Definitions
The LEDs show the following modes of operation for the device.
Device Status Alternate Mode Standard Mode
No Power All LEDs OFF
FL500 UV/IR, FL500-H2 Flame Detector 7
US 2 Description

Device Status Alternate Mode Standard Mode
Initial Power On All LEDs blink alternately for 10 s
Ready/Normal Green LED = ON Green LED = ON with heartbeat
(5 s ON, 0.5 s OFF)
Yellow LED = OFF
Red LED = OFF
Fault - COPM Green LED = ON Green LED = OFF
Yellow LED = Blinking slowly (1 Hz)
Red LED = OFF
Fault - Other Green LED = ON Green LED = OFF
Yellow LED = ON
Red LED = OFF
Alarm Low Green LED = ON Green LED = OFF
Yellow LED = OFF
Red LED = Blinking slowly (1Hz)
Alarm High Green LED = ON Green LED = OFF
Yellow LED = OFF
Red LED = ON
3 Installation
WARNING!
• Do not install or operate a device that is damaged.
• Install the device in a location away from conditions (such as high-pressure steam) where electrostatic charge can collect
on nonconducting surfaces. This equipment uses an external nonmetallic coating. If extreme levels of electrostatic charge
collect, ignition can occur.
• Make sure that there is no physical blockage from permanent objects such as structures and equipment or temporary
objects such as personnel and vehicles in the sensor's field of view. Ifthere is physical blockage in the sensor's field of
view, the device cannot accurately monitor the area for flame.
• Keep the device safe from vibration and mechanical shock, which can cause damage.
Failure to follow these warnings can result in serious personal injury or death.
3.1 Required Tools
• 5mm Allen wrench (included with the device)
• Flat-blade screwdriver, maximum 1/8in. width
• No. 2Philips screwdriver
• 10mm Allen wrench
• Adjustable wrench
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3.2 Locations
Use the information in Section 3.2.1 Field of View and Section 3.2.2 Environmental Factors to select the best location to
install the device.
3.2.1 Field of View
Gas Performance:
HEPTANE
65°
60°
55°
45°
30°
15° 0°
20’
25’
30’
35’
40’
45’
50’
55’
60’
65’
70’
75’
80’
85’
90’ 15°
30°
45°
55°
60°
65°
65°
60°
55°
45°
30°
15°
0° 20’25’30’35’
40’
45’50’
55’60’
65’70’
75’80’
85’90’
15°
30°
45°
55°
60°65°
Horizontal High Med Low
Vertical High Med Low
Gas Performance:
HEPTANE
90’ 55’ 45’
55’ 45’
55’ 45’
90’
90’
75’
0°
± 15°
30°
- 30°
45°
75’- 60°
50’ 40’ 30’65°
50’ 40’ 30’- 65°
- 45°
60°
90’ 55’ 45’
55’ 45’
55’ 45’
90’
90’
75’
0°
± 15°
30°
- 30°
45°
60’- 60°
50’ 40’ 30’65°
50’ 40’ 30’- 65°
- 45°
60°
Figure 3 Heptane Field of View
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Gas Performance:
METHANE
65°
60°
55°
45°
30°
15° 0°
20’
25’
30’
35’
40’
45’
50’
55’
60’
65’
70’
75’
80’ 15°
30°
45°
55°
60°
65°
65°
60°
55°
50°
45°
30°
15°
0° 20’
25’
30’
35’
40’45’
50’
55’60’
65’
70’75’
80’
15°
30°
45°
55°
50°
60°65°
Horizontal High Med Low
Gas Performance:
METHANE
Vertical High Med Low
80’ 60’ 45’
80’
0°
± 15°
30°
- 30°
40°
80’- 45°
65’ 50’ 45’55°
65’ 50’ 45’- 55°
40’ 35’60°
35’ 35’- 60°
- 40°
45°
80’ 60’ 45’
80’ 50’
80’ 50’
35’
35’
65’ 45’
65’ 45’
0°
± 15°
30°
− 30°
40°
− 40°
45°
− 45°
50°
− 50°
55°
− 55°
50’ 35’
60°
60’ 35’
− 60°
Figure 4 Methane Field of View
10 FL500 UV/IR, FL500-H2 Flame Detector
3 Installation US

Gas Performance:
METHANOL
30°
15° 0°
10’
15’
20’
25’
30’
35’
40’
15°
30°
45°45°
40°40°
50°50°
55°55°
60°60°
30°
15°
0° 10’
15’20’
25’
30’35’40’
15°
30°
45°
45°
40°
40°
50°
50°
55°
55°
60°
60°
Horizontal High Med Low
Gas Performance:
METHANOL
Vertical High Med Low
40’ 30’ 25’0°
± 15°
30°
− 30°
± 40°
45°
− 45°
40’ 30’ 25’50°
40’ 30’ 25’− 50°
20’55°
20’− 55°
25’ 20’60°
25’ 20’− 60°
40’ 30’ 25’0°
± 15°
30°
− 30°
40°
− 40°
50° 40’ 30’ 25’
− 50° 40’ 30’ 25’
55° 20’
− 55° 20’
60°
30’ 20’
30’ 20’
− 60°
Figure 5 Methanol Field of View
FL500 UV/IR, FL500-H2 Flame Detector 11
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Gas Performance:
PROPANE
30°
15° 0°
10’
15’
20’
25’
30’
35’
40’
45’
50’
55’
60’
15°
30°
45°45°
40°40°
50°50°
55°55°
60°60°
30°
15°
0° 10’
15’20’
25’
30’35’40’45’
50’55’60’
15°
30°
45°
45°
40°
40°
50°
50°
55°
55°
60°
60°
Horizontal High Med Low
Vertical High Med Low
Gas Performance:
PROPANE
60’ 45’ 25’0°
± 15°
30°
− 30°
40°
− 40°
25’45°
25’
− 45°
60’ 45’ 20’
55°
60’ 45’ 20’− 55°
45’ 25’60°
45’ 30’− 60°
60’ 45’ 25’0°
± 15°
30°
− 30°
40°
− 40°
20’45°
20’
25’
25’
25’
25’
35’
35’
− 45°
60’
55°
60’− 55°
50’60°
50’− 60°
Figure 6 Propane Field of View
12 FL500 UV/IR, FL500-H2 Flame Detector
3 Installation US

Gas Performance:
ETHANE
30°
15° 0°
10’
15’
20’
25’
30’
35’
40’
45’
50’
55’
60’
15°
30°
45°45°
40°40°
50°50°
55°55°
60°60°
30°
15°
0° 10’15’20’25’30’35’40’45’50’55’60’
15°
30°
45°
45°
40°
40°
50°
50°
55°
55°
60°
60°
Horizontal High Med Low
Gas Performance:
ETHANE
Vertical High Med Low
60’ 40’ 30’0°
± 15°
30°
− 30°
40°
− 40°
45°
30’ 25’
30’ 25’
40’ 30’
40’ 30’
− 45°
60’
60’
55’
55’
50°
− 50°
60°
− 60°
60’ 40’ 30’0°
± 15°
30°
− 30°
40°
− 40°
45°
30’ 25’
30’ 25’
40’ 30’
40’ 30’
− 45°
60’
60’
55’
55’
50°
− 50°
60°
− 60°
Figure 7 Ethane Field of View
FL500 UV/IR, FL500-H2 Flame Detector 13
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Gas Performance:
BUTANE
30°
15° 0°
10’
15’
20’
25’
30’
35’
40’
45’
50’
55’
15°
30°
45°45°
40°40°
50°50°
55°55°
60°60°
30°
15°
0° 10’15’20’25’30’35’40’45’50’55’
15°
30°
45°
45°
40°
40°
50°
50°
55°
55°
60°
60°
Horizontal High Med Low
Gas Performance:
BUTANE
Vertical High Med Low
55’ 35’ 25’0°
± 15°
30°
− 30°
40°
− 40°
45°
25’ 20’
25’ 20’
25’
25’
− 45°
20’
20’
55’
55’
50°
− 50°
55°
− 55°
45’
45’
60°
− 60°
55’ 35’ 25’0°
± 15°
30°
− 30°
40°
− 40°
45°
25’ 20’
25’ 20’
25’
25’
− 45°
55’
55’
55°
− 55°
45’
45’
60°
− 60°
Figure 8 Butane Field of View
14 FL500 UV/IR, FL500-H2 Flame Detector
3 Installation US

Response Times and Field of View data were derived by testing the FL500-H2flame detector with a hydrogen flame
from a 6inches square custom burner with 1600orifices. The flame height was approximately 32 inches.
Gas Performance:
HYDROGEN
Horizontal High Med Low
Gas Performance:
HYDROGEN
Vertical High Med Low
60’ 40’ 30’
40’ 30’
0°
± 15°
± 30°
40°
45°
60’
± 55° 40’
50’ 35’
50’ 35’
60°
- 65°
- 45°
± 50°
60’ 25’ 20’
60’ 25’ 20’
60’ 25’ 20’
25’
60’ 20’ 20’
60’ 25’ 20’
20’ 20’
60’
50’
50’ 15’
15’
0°
± 15°
± 30°
40°
45°
- 45°
- 50°
± 55°
60°
- 60°
65°
60’
40’ 30’60’
30’
40’
60’
40’60’ 30’
20’
-65
-60
-55
-50 50
-45
-30
-15 0
5’
10’
15’
20’
25’
30’
35’
40’
45’
50’
55’
60’
15
30
45
40
55
60
65
-65
-60
-55
-50 50
-45
-30
-15 0
5’ 10’ 15’ 20’ 25’ 30’ 35’ 40’ 45’ 50’ 55’ 60’
15
30
45
40
55
60
65
Figure 9 Hydrogen Field of View FL500-H2horizontal
FL500 UV/IR, FL500-H2 Flame Detector 15
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3.2.2 Environmental Factors
WARNING!
Do NOT install the device in an area where temperatures will be more than 185°F (85°C).
Failure to follow this warning can result in serious personal injury or death.
Make sure that the device is in an area where ice, dirt, or debris cannot collect on the optical window. If ice, dirt, or debris
collects on the optical window, a COPM Fault occurs.
To maintain the device enclosure's IP66/IP67 and Type6P ingress ratings, use a nonhardening sealant to install stopping
plugs on conduit/cable entries that are not used.
3.3 Mounting
Use the mounting bracket (PN 71370-1) and hardware to install the device on a wall, pole, or other surface. The design of the
mounting bracket lets you adjust optical alignment while keeping the device in a fixed position.
To attach the mounting bracket to drywall, install at least two fasteners to the stud behind the drywall to give support for the
weight of the device. The recommended fastener is a 3-in.#12screw.
Use the dimensions shown in Figures 10 through 14 to install the device correctly. Make sure that the device:
• Is in a location where personnel and objects cannot cause a blockage of the field of view
• Is in a location that is convenient for visual inspection and cleaning
• Is in a location where ice, dirt, or debris cannot collect on the optical window
• Point downward about 15-20 degrees to prevent dust and moisture from collecting on the optical window.
General Monitors does not recommend the use of cable shoes or crimps on any junction box or housing wiring
terminals. Poor crimping can cause a bad connection when temperature variations occur.
Figure 10 FL500 Outline Drawing, Front View
16 FL500 UV/IR, FL500-H2 Flame Detector
3 Installation US

Figure 11 FL500 Outline Drawing, Side View
Figure 12 FL500 and Mounting Bracket, Side View
Figure 13 FL500 and Mounting Bracket, Top View
FL500 UV/IR, FL500-H2 Flame Detector 17
US 3 Installation

Figure 14 FL500 and Mounting Bracket, Rear View
3.4 Wiring
WARNING!
• An approved electrician must do electrical wiring.
• All wiring must satisfy the requirements of the applicable NEC, CEC, and local electrical safetycodes.
• Install a conduit seal within 18 in. (46 cm) of the device enclosure.
• Make sure that all wiring is applicable for use at an ambient temperature of 199.6ºF (93.1°C).
• Before installing the wiring for the device, disconnect the power source.
• Read all electrical warnings and wiring requirements before connecting power to the device.
• In order to maintain the environmental and hazardous area ratings of the detector, installconduit adapters or plugs in the
enclosure per applicable agency requirements.
• The device wiring can be damaged by electrostatic discharge (ESD). When you do work with the device wiring, be careful
to touch only the connection points. The warranty does not supply coverage for components that are damaged by ESD.
• Do NOT install wiring in a hazardous atmosphere. Otherwise, electrical shock or ignition can occur.
Failure to follow these warnings can result in serious personal injury or death.
Install all wiring connections through the base entries to the terminal block (TB). The terminal block accepts 14 - 22 AWG (2.1 -
0.3 mm2) stranded or solid-core wire.
If conduit is used, to prevent corrosion in the housing due to moisture or condensation, a drain loop in the conduit is
recommended.
For enclosure entry points, a non-hardening sealant should be used on threads.
18 FL500 UV/IR, FL500-H2 Flame Detector
3 Installation US

Figure 15 FL500 Housing and Base
Remove the insulation from each wire to 0.25 in. (0.64 cm).
Use the correct cables for the ambient temperature where the device is installed.
Fault 2 Alarm Reset
No Connection
No Connection
Alarm Test
Alarm High 2
Alarm High 1 Alarm High Relay
Alarm Low Relay
Normally
Open Switch
Normally
Open Switch
Alarm High C
Alarm Low C
Alarm Low 1
Alarm Low 2
Fault C
Fault 1
No Connection
+ 24 VDC
0-20 mA
+ −
COM (24 V-return)
Chassis Ground
Data −
Data +
RS485
TB2TB1
11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10
Control Device
PLC, DCS, ETC
Power Supply
Figure 16 Wiring Diagram
Protection Circuits for Relay Contacts
WARNING!
Protect relay contacts from transient and over-voltage conditions. Attach a clamp to all inductive loads (bells, buzzers, relays)
on dry relay contacts as shown. Inductive loads that do not have a clamp attached can cause voltage spikes of more than
1000 Volts. Voltage spikes of this magnitude can cause false alarms and damage to the contacts.
Failure to follow this warning can result in serious personal injury or death.
(1) To connect the wire to the terminal block, install the conductor in the connection space as shown.
(2) Use a flat-blade screwdriver to tighten the related screw terminal.
3.5 Terminal Connections
There are 20 terminal connections. The following sections give descriptions and specifications for each connection.
FL500 UV/IR, FL500-H2 Flame Detector 19
US 3 Installation

TERM# TERM#
TB2TB1
11 12 13 14 15 16 17 18 19 20
12345678910
Chassis
COM (24 V - Return)
+ 24 VDC
0-20 mA
No Connection
Data +
Data −
Fault 1
Fault C
Fault 2
Alarm Low 2
Alarm Low 1
Alarm Low C
Alarm High C
Alarm High 1
Alarm High 2
Alarm Test
No Connection
No Connection
Alarm Reset
Figure 17 Field Terminations
3.5.1 TB2, Alarm High Relay Connection
The output for the SPDT Alarm High relay has a time delay that can be set for 2, 4, 8, or 10 seconds. Alarm High output can be
normally energized or normally de-energized, latching or non-latching.
All options can be set through Modbus, HART, or the DIP switch. Refer to Section 4.2 Changing Device Settings for
instructions.
TB2
Position
Alarm High
Relay
Relay Contact
(De-Energized)
Relay Contact
(Energized)
17 C Common Common
16 1 Normally Closed Normally Open
15 2 Normally Open Normally Closed
3.5.2 TB2, Alarm Low Relay Connection
The output for the SPDT Alarm Low relay is immediate. Alarm Low output can be normally energized or normally de-energized,
latching or non-latching.
All options can be set through Modbus, HART, or the DIP switch. Refer to Section 4.2 Changing Device Settings for
instructions.
TB2
Position
Alarm Low
Relay
Relay Contact
(De-Energized)
Relay Contact
(Energized)
18 C Common Common
20 FL500 UV/IR, FL500-H2 Flame Detector
3 Installation US