Viking VSF303 User manual

VSF303 Multi Spectrum IR Flame Detector

2
Safety and Technical Manual
Rev: 2
Form No. F_020521
VSF303 Flame Detector
This document is strictly private and confidential, reproduction without Viking Corporation approval is prohibited. © 2021 The Viking Group Inc.
Viking Corporation
5150 Beltway Dr. SE
Caledonia MI 49316
Form No. F_020521 Rev 2
Ref: 3303.0001 Rev: 2.2 ECN:4652

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Safety and Technical Manual
Rev: 2
Form No. F_020521
VSF303 Flame Detector
This document is strictly private and confidential, reproduction without Viking Corporation approval is prohibited. © 2021 The Viking Group Inc.
HELP US TO HELP YOU
Every effort has been made to ensure the accuracy in the contents of our documents; however,
Viking can assume no responsibility for any errors or omissions in our documents or their
consequences. Viking would greatly appreciate being informed of any errors or omissions that may
be found in our documents.
Please email Viking Technical Services at [e-mail] or call 1-877-354-5464.
Please reference the Form No. and Rev shown in the upper right corner of this page.
THANK YOU
Contents
1Introduction................................................................................................................................5
Detector Features...............................................................................................................5
2Safety Instructions .....................................................................................................................6
Warnings ............................................................................................................................6
Cautions .............................................................................................................................6
Important Safety Notices ....................................................................................................6
EN 54-part 10 Limitation of use ..........................................................................................8
3Installation .................................................................................................................................8
Detector Enclosure .............................................................................................................8
Mounting & Orientation .......................................................................................................8
Wiring Procedure..............................................................................................................10
0-20mA Output .................................................................................................................11
Relay Output.....................................................................................................................12
Internal Inter-connections .................................................................................................13
Installation Checklist .........................................................................................................14
3.7.1 Mechanical ................................................................................................................14
3.7.2 Electrical....................................................................................................................15
4System Design Guidelines.......................................................................................................16
Power Supply ...................................................................................................................16
Cable Selection ................................................................................................................16
DC Power .........................................................................................................................16
5Application Guidelines .............................................................................................................17
Positioning Requirements.................................................................................................17
Detection Coverage..........................................................................................................17
Exposure to Flare Radiation .............................................................................................17
Optical Contamination ......................................................................................................18
Enclosed Areas ................................................................................................................18
Detector Sensitivity...........................................................................................................18

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VSF303 Flame Detector
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Detector Alarm Delay........................................................................................................18
6Maintenance and Commissioning ............................................................................................20
Procedure.........................................................................................................................20
Functional Testing ............................................................................................................22
7Fault Finding............................................................................................................................23
Removal of the Electronics ...............................................................................................23
Replacement of the Electronics ........................................................................................23
Diagnostics.......................................................................................................................23
LED Indication ..................................................................................................................24
Power Fault ......................................................................................................................25
8Technical Specification ............................................................................................................26
Detector Information .........................................................................................................26
Electrical Specification......................................................................................................26
Mechanical Specification ..................................................................................................26
Environmental Specification..............................................................................................26
Certification and Approvals ...............................................................................................27
Operating Specification.....................................................................................................27
VSF303 Detector Ordering Information.............................................................................28
Detector Accessories and Spares.....................................................................................28
9Appendix A - Acronyms, Terms & Abbreviations......................................................................29
10 Appendix B - Field of View ...................................................................................................30
11 Appendix C - FM Approval Performance Report...................................................................31
12 Appendix D - IEC 61508 Failure Rate Data ..........................................................................34

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Safety and Technical Manual
Rev: 2
Form No. F_020521
VSF303 Flame Detector
This document is strictly private and confidential, reproduction without Viking Corporation approval is prohibited. © 2021 The Viking Group Inc.
1 Introduction
This safety and technical manual applies to the Viking Multi Spectrum IR3 Flame Detector (VSF303)
hardware version 1.0 and above.
The Viking VSF303 is a triple IR flame detector. It uses three IR sensors, digital signal processing
hardware and firmware algorithms to interpret the radiant characteristics of flame.
The Viking flame detection range are the safest and most advanced flame detectors on the market
today. Our worldwide installed base has proven that the Viking technology is robust, even in the
harshest of environments.
FM Approvals ensures that our flame detection firmware and hardware is fit for purpose through
rigorous research and testing to a range of fire types and various potential false alarm stimuli. This
testing proves that the VSF303 has an unsurpassed false alarm immunity.
The VSF303 has been designed for use in standalone operation.
Detector Features
•The VSF303 has a 90° cone of vision with a range of 200 ft (60 m) to a 1 ft2(0.1 m2) pan fire
of n-heptane.
•Three detection sensitivity settings allowing the user to select the sensitivity that is most
suitable for their application.
•Superior false alarm immunity to common sources of unwanted alarms such as hot process
and hot work.
•Advanced optical verification test assuring readiness to perform when needed.
•Outputs include both relay contacts and 0-20mA.
•Separate termination chamber for ease of installation.
•Certified Flame Simulator VSF3008 ITEST verifies operation from distances of 10 to 26 ft
(3 to 8 m).
•VSF303 can operate via a standard 3 or 4 wire termination.
•Microprocessor controlled heated optics increases resistance to moisture and ice.

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VSF303 Flame Detector
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2 Safety Instructions
For the correct and effective use of this equipment, to maintain safety and avoid hazards it is
essential that you read and understand these instructions fully and act accordingly BEFORE
installing, operating, or maintaining the equipment.
PAY ATTENTION TO ALL SAFETY WARNINGS AND CAUTIONS
Warnings
This equipment is certified and intended for use in potentially hazardous areas. Install and use the
equipment in accordance with the latest regulations. The end user shall close any unused entries
using suitably certified blanking elements to maintain the housing’s type of protection.
For European (ATEX) installations IEC/EN60079-14 ‘Electrical Installations in Hazardous Areas’
and ICE/EN60079-17 ‘Inspection and Maintenance in Hazardous Areas’ should be strictly observed.
The IR3 type flame detector; Viking VSF303, is to be installed in places where there is a low risk of
mechanical damage.
For installations in North America the National Electrical Code (NEC) should be strictly observed. In
other countries the appropriate local or national regulations should be observed.
The equipment must be properly earthed to protect against electrical shock and minimize electrical
interference.
Do not drill holes in any housing or enclosure as this will invalidate the explosion protection. Ensure
that the enclosure lid is fully tightened and locked into position before energizing the equipment.
Do not open the enclosure in the presence of an explosive atmosphere.
All permits and proper site procedure and practices must be followed, and the equipment must be
isolated from the power supply before opening the enclosure in the field.
Operators must be properly trained and aware of what actions to take in the event of a fire being
detected.
Cable to be used for installation is to be selected with a temperature rating of greater than 77 °F
(25 °C) above the maximum ambient temperature. The metric cable entries are fitted with an
internal stop. This will result in threads of the cable gland being visible. Do not over tighten.
Cautions
Use only approved parts and accessories with this equipment.
Do not attempt to replace the window as the sapphire and the front cover are individually matched
pairs to meet the stringent requirement of the hazardous area certification.
The threaded portions of the detector are flame paths. These threads and the flame paths are not to
be repaired.
To maintain safety standards, commissioning and regular maintenance should be performed by a
qualified person.
Important Safety Notices
Pay attention to the guidelines given throughout this document. If in any doubt about the instructions
listed within this manual, then please contact Viking.

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VSF303 Flame Detector
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Viking takes no responsibility for installation and/or use of its equipment if it is not in accordance
with the appropriate issue and/or amendment of the manual. Viking reserve the right to change or
revise the information contained herein without notice and without obligation to notify any person or
organization of such action.
Only those parameters and configurations highlighted with the FM diamond ( ) have been
tested and approved by Factory Mutual.
Warning
Do not open the detector assembly in a hazardous area. The detector contains limited serviceable
components and should only be opened by trained personnel.
Caution
The wiring procedures in this manual are intended to ensure functionality of the device under
normal conditions. Due to the many variations in wiring codes and regulations, total compliance to
these ordinances cannot be guaranteed. Be certain that all wiring complies with all local ordinances.
If in doubt, consult the authority having jurisdiction before wiring the system. Installation must be
done by trained personnel.
Caution
To prevent unwanted actuation or alarm, extinguishing devices must be inhibited/isolated prior to
performance testing or maintenance.
Detector Orientation
Detectors should be mounted with the earth stud directly below the lens.
Detector Positioning
Detectors should be positioned to provide the best unobstructed view of the area to be protected.
The following factors should also be taken into consideration:
Identify all high-risk fire ignition sources. Ensure that enough detectors are used to adequately
cover the hazardous area.
Locate and position the detector so that the fire hazard(s) are within both the field of view and
detection range of the device.
For best performance, the detector should be mounted on a rigid surface in a low vibration area.
Extremely dense fog or blizzard conditions could eventually block the vision of the detector.
For indoor applications, if dense smoke is expected to accumulate at the onset of a fire, mount the
detector on a side wall approximately 3 to 6 ft (1 to 2 m) below the ceiling.
The VSF303 has three sensitivity settings, which may be changed via a Viking application.
The flame detector carries out continuous internal hardware diagnostic testing to ensure correct
operation is relayed to the control system.
The VSF303 is not designed to annunciate diagnostic failure of signal returns via external wiring.
Control systems and fire panels generally have fault monitoring for such an eventuality.

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VSF303 Flame Detector
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EN 54-part 10 Limitation of use
The VSF303 is not approved for use in oxygen-enriched atmospheres.
As the VSF303 responds to flame, it cannot be used in locations where flare stacks are within its
field of view or a reflected view is present without triggering alarms.
As the VSF303 responds to CO2emissions of a flame the VSF303 cannot detect non-hydrocarbon
fires, such as those using pure hydrogen, silane, and sulphur as fuel.
The sensitivity of the VSF303 is reduced by obscurants such as smoke, fog, and other airborne
particulates. The VSF303 may be blinded by extremely dense obscurants.
Arc welding should not take place within 32 ft (10 m) of the VSF303 when using the highest
sensitivity setting.
3 Installation
The VSF303 design has been developed to allow simple installation. The detector comprises two
key components, the detector enclosure, and the detector internal assembly. The detector assembly
located in the front of the enclosure should not be removed except by trained personnel.
Unauthorized removal or disassembly of the detector assembly will invalidate the warranty. Only the
rear end cap can be removed for terminal access.
Detector Enclosure
The detector electronics are housed in an enclosure certified for use in hazardous areas. For the
exact certification and conditions of use see certification label on the device, or the example drawing
below:
The detector comprises the front window cover including the window, the rear enclosure cover, the
enclosure body, certification rating label (see above) and the mounting bracket.
The flame detector is supplied preassembled and includes the mounting bracket. However, it is not
supplied with a mounting support and fixings, cabling, or glands.
Mounting & Orientation
The mounting bracket allows the detector’s vertical orientation to be adjusted from 0 to 45° and
allows a horizontal rotation of +/-45° when mounted from above.
Figure 1: Detector Mounting Bracket

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Figure 2: Ceiling Mount
Figure 3: Wall Mount
Firm, vibration free mountings are essential for trouble free operation of optical systems and the
detector should be fixed to a rigid mounting. When mounting on a wall in this orientation allow for
the cable gland and cable as this may restrict the downward rotation of the detector.

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VSF303 Flame Detector
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Wiring Procedure
The wiring terminals are in the rear section of the detector enclosure and are accessible by removal
of the end cap.
The front section of the enclosure should only be accessed by trained personnel.
The terminal schematic detailed below shows the view looking inside the detector following removal
of the end cap.
Figure 4: Terminal Schematic
The detector has two types of alarm output available simultaneously.
• 0-20mA (source non-isolated)
• Relay (Alarm & Fault)
Listed below are wiring options dependent on the functional requirements of the detector.

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VSF303 Flame Detector
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0-20mA Output
The following wiring connection diagram shows correct wiring of the detector when a 0-20mA output
is required.
Figure 5: 3 Wire Termination
Factory Fixed Values
Current Output
Event
0mA
Power/Detector Fault
1mA
Low Supply Voltage Fault
1.5mA
Optical Fault
4mA
Healthy
18mA
Alarm
21mA
Over-range
Notes:
Note 1 -The tolerance on the above outputs is +/- 0.3mA current with a maximum loop resistance
of 500 ohms.
Note 2 –Additional 0-20mA values are configurable and must be specified when ordering if
required. The optical fault signal may be configured at 2mA as opposed to 1.5mA and the alarm
signal may be increased to 20mA.
Note 3 -The VSF303 can be factory-configured with an Aux alarm delay (20mA) of between 0
and 10 seconds in 1 second steps over and above the normal response times of the 18mA alarm
signal. If the Aux alarm signal is delayed, the 18mA alarm signal will precede the 20mA signal
giving the normal response times as tested by Factory Mutual to FM3260. If the 20mA alarm
signal is delayed, it is considered an Aux alarm level.
Note 4 – The 0-20mA signal has HART ® 7 protocol superimposed on top of it to give access to
more diagnostic information. See HART ® 7 Technical Note.

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VSF303 Flame Detector
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Relay Output
The following wiring connection diagrams shows wiring the detector when a relay output is required.
Reversal of polarity across terminals 1 & 2 enables Viking RS485 communication on terminals 3 &
4. This communication protocol, when used with Viking applications, allows configuration changes
to the detector.
Figure 6: Relay Configuration Termination
NOTE: EOL and alarm resistors values are defined by the client and the control system/fire
panel which the detectors are being integrated into.

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Internal Inter-connections
The following diagram shows the internal inter-connections of the alarm and fault relay contacts and
jumpers. Each field connection is listed on this diagram for clarity.
Figure 7: VSF303 Internal Inter-connections
VSF303
VSF303
VSF303

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VSF303 Flame Detector
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Installation Checklist
Experience has shown that poor installation and commissioning practice may result in an unreliable
fire detection system that fails to meet the site performance targets. Before installing the detector, it
is important to consider where it is to be located and how it is to be mounted. To maintain
compliance with the EMC regulations it is essential the electrical installation be engineered
correctly.
3.7.1 Mechanical
Notes
When locating the detector consideration should be given to maintenance access to the
detector. The detector mounting should be secure and vibration free.
It is advisable to check the detection locations, prior to fabrication of the mounting
supports, as changes are frequently made during construction at site which can affect
detector coverage.
The installation should allow space for subsequent detector removal, for maintenance or
repair, to be easily achieved.
1
The detector should be fixed to a stable supporting structure using the mounting bracket
provided. The supporting structure must allow for horizontal adjustment of the detector
orientation. The support structure should be in place prior to detector installation.
Information on mounting is available from Viking.
2
The threaded flame path of the enclosure cover and body must be protected from
damage during installation. Any such damage can destroy the validity of the enclosure.
3
The detector electronics shall be protected from mechanical damage and external
sources of EMI such as X-rays, RFI and electrostatic discharge. The detector should not
face directly towards the sun.
4
Fit the mounting bracket to the support structure using 5/16-inch (8 mm) bolts (not
provided). The detector (bracket) should be oriented to provide the desired coverage.
5
The detector enclosure body should be fitted to the mounting bracket. The bolts locate
into the bracket. Twist the enclosure to locate the bolts; these are then tightened using a
6mm Allen key.
6
Ensure the detector is orientated such that the earthing stud is directly beneath the lens.
7
Glanding should be carried out by trained personnel. The gland should be fitted in line
with installation standards for potentially explosive atmospheres that is 5 full threads
minimum with the IP seal washer fitted at the bottom of the thread. This sealing
arrangement will result in several threads of the cable gland being visible. The gland
should be torqued between 11 to 15 lb. ft (15 to 20 N m).
Note – The IP seal washer only applies to metric threads.

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3.7.2 Electrical
Notes
It is advisable to check the detection locations, prior to fabrication of the mounting
supports, as changes are frequently made during construction at site. Detector cabling
must be segregated from cables carrying high-speed data or high energy and/or high
frequency signals and other forms electrical interference. The detector requires a clear
unobstructed view of the local hazard. To avoid local obstructions, such as pipework and
cable trays, a 6 ft (2 m) helix should be allowed in the detector cabling. The detector
should only be fitted just prior to commissioning the detector. Experience shows that the
detector can be damaged due to cable testing operations (Insulation Tests, etc.).
1
Isolate all associated power supplies. Ensure that they remain OFF until required for
commissioning.
2
The threaded flame path of the enclosure cover and body must be protected from
damage during installation. Any such damage can destroy the validity of the enclosure.
3
The electronics subassembly shall be protected from mechanical damage and external
sources of EMI such as X-rays, RFI and electrostatic discharge.
4
The enclosures external earth stud should be connected to a local earth point.
5
Remove the transit plug(s) from the enclosure body gland entries.
6
Fit approved cable glands.

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4 System Design Guidelines
The following guidelines are intended to assist with the electrical design and engineering of systems
where it is intended that flame detectors will be used.
Power Supply
The detector requires an absolute minimum supply voltage of 18Vdc, as measured at the detector
terminals. The system power supply voltage and power distribution should be arranged such that on
the longest cable run the detector(s) has a supply voltage of greater than 18Vdc.
Cable Selection
Cable to be used for installation is to be selected with a temperature rating of greater than 77 °F
(25 °C) above the maximum ambient temperature.
The metric cable entries are fitted with an internal stop. This internal stop has an IP washer
mounted directly above it. Ensure this is fitted to maintain the ingress protection. This will result in
threads of the cable gland being visible. Do not over tighten.
The installation and local regulations and standards determine the overall cable specification. This
section specifies suitable cable characteristics to ensure correct operation of the flame detector.
DC Power
NOTE: Table 2 shows an absolute maximum for cable length; try not to approach this value.
DO NOT ground any cable shields at the detector housing.
Table 2: Maximum Cable Lengths (24Vdc supply)
Installation
based on 24V
nominal supply
Number of
Flame
Detectors
Maximum
Power (W)
Maximum Cable
Length (m) with
1.5mm2
Conductors
(12Ω/km)
Maximum Cable
Length (m)with
2.5mm2
Conductors
(7.6Ω/km)
Heater on
1
12W @ 24Vdc
500
780
Heater off
1
3W @ 24Vdc
2000
3000
Table 3: AWG Conversions
Cross Sectional Area (mm2)
American Wire Gauge
(AWG)
Typical Conductor Resistance
per km (3280 ft.)
DC Ω/km @ 20°C (Approx.)
0.5
22
36
1.0
18
19
1.5
16
12
2.5
14
7.6

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VSF303 Flame Detector
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5 Application Guidelines
In considering the application of the detector it is important to know of any conditions that may
prevent the detector from responding. The detector provides reliable response to hydrocarbon
flames within its field of view, and insensitivity to common false alarm sources. Solid obstructions or
a direct view of intense light sources may result in a reduction in the coverage and/or a reduction in
the detector sensitivity. Scaffolding or tarpaulins in the detector’s field of view may reduce coverage.
Contamination of the detector window may result in a reduction in sensitivity.
The detector has a 90° conical field of view. The location and orientation of the detector in relation
to the protected area determines the actual footprint. Achieving the desired coverage depends on
congestion within the protected space, the location of the detector(s) and the distance of the
detector from the hazard. It may be necessary to install more than one detector within an area to
achieve adequate coverage.
The detector sensitivity, expressed as fire size at a distance, is determined by the radiant heat
output of the fire. This is a function of the fuel source, how it is released and distance from the
detector to the fire.
In common with other forms of flame detection the detector’s sensitivity is reduced and potentially
blinded by dense obscurants such as smoke, fog, and other airborne particulates. The detector is
insensitive to arc welding; however, this should not be conducted within 32 ft (10 m) of the detector.
Positioning Requirements
The following guidelines have been based on operational feedback, reflecting commonly
experienced problems which can be traced to a failure to observe the following:
•Ensure the mounting position is free from vibration or movement.
•Prevent accidental knocking or forcing out of alignment.
•Isolate as far as possible from local electrical interference sources.
•Ensure sufficient detection to achieve adequate coverage for all likely hazards.
•Minimize exposure to contamination of the detector face plate.
•Ensure ease of maintenance access to detector (i.e., direct ladder or scaffold access).
•Do not allow the VSF303 to have direct view of hot surfaces.
•Ensure that the VSF303 has no direct view or reflected view of a friendly fire.
•The detector should be aimed downward by at least 10° to 20°.
All these issues are of crucial importance to a successful installation and they should be afforded
great attention during the detailed design, construction, and commissioning phases of the work.
Detection Coverage
Detector locations can be chosen from computer models or from site surveys. The detectors should
be aligned to view the intended hazard considering any obstruction and congestion. Software
analysis of the actual detector coverage may be required to ensure adequate coverage of the
hazards. This analysis can also be used to optimize the number of detectors and the loop
configuration. The cones of vision are detailed in Appendix B.
Exposure to Flare Radiation
Flame detectors are frequently used where hydrocarbon fire hazards are expected; these are quite
often processing plants where a flare stack is in use nearby. The detector shall not have a direct
view of the flare or a reflected view of the flare.

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Optical Contamination
There are many sources of contamination such as oil, water (deluge water, rain, and sea-spray),
snow, ice, and internal misting. Excessive contamination of the detector faceplate may result in an
increased maintenance requirement and potentially reduce the detector’s sensitivity. Where
detectors are mounted at low level, care should be taken to avoid contamination (such as water and
oil) from equipment above the detector. Care should be taken in sighting the detector to minimize
the likelihood of such contamination. The detector is designed such that an optical fault is generated
when half of the detection range remains. This is indicated by the fault output and is evident by the
yellow color of the LED on the face of the detector. The optical fault condition indicates that the
detector requires cleaning or service. The optical fault indication is self-clearing.
Enclosed Areas
In enclosed areas, if dense smoke is expected to accumulate at the onset of the fire, the detector
should be mounted 3 to 6 ft (1 to 2 m) below the ceiling level.
Detector Sensitivity
The detector’s response to a fire is a function of the fuel source and how it is released, fire size and
distance, orientation to the detector and local ambient conditions. The typical figures are based on
in-house tests except when marked with the FM logo, these tests were conducted and certified by
Factory Mutual. As with all tests the results must be interpreted according to the individual
application considering all possible variables.
The detector sensitivity to different fuel sources is dependent on the radiant heat output of the flame
and the detectors typical response is shown below (see table 4). The detector will only detect
hydrocarbon fires.
Detector Alarm Delay
The Detector can be factory configured with an Aux alarm delay (20mA) of between 0 and 10
seconds in 1 second steps over and above the normal response times of the 18mA alarm signal. If
the Aux alarm signal is delayed the 18mA alarm signal will precede the 20mA signal giving the
normal response times as tested by Factory Mutual to FM3260. The 20mA alarm signal if delayed is
considered an Aux alarm level.

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Table 4: Typical VSF303 Response Characteristics High sensitivity (200 ft (60 m)). For all FM
approved results see Appendix D
Fuel
Fire Size
Distance
FM
Methane Fire
2 ft (0.6 m) plume
height
165 ft (50 m)
Ethanol Fire
1ft2 (0.1m2) pan
136 ft (42 m)
Diesel Fire
1ft2 (0.1m2) pan
165 ft (50 m)
Crude Oil (heavy fuel oil) Fire
1ft2 (0.1m2) pan
165 ft (50 m)
Wax Inhibitor (Clear 10) Fire
1ft2 (0.1m2) pan
165 ft (50 m)
Anti-Foam (Surflo AF-300) Fire
1ft2 (0.1m2) pan
165 ft (50 m)
Wood Stack Fire
1ft2 (0.1m2) pan
165 ft (50 m)
n-heptane Fire
1ft2 (0.1m2) pan
200 ft (60 m)
n-heptane Fire in direct sunlight
1ft2 (0.1m2) pan
200 ft (60 m)
n-heptane Fire in modulated sunlight
1ft2 (0.1m2) pan
200 ft (60 m)
n-heptane Fire in the presence of Arc welding
1ft2 (0.1m2) pan
200 ft (60 m)
n-heptane Fire in the presence of a 500-Watt
lamp
1ft2 (0.1m2) pan
200 ft (60 m)
Gasoline Fire
1ft2 (0.1m2) pan
200 ft (60 m)
JP4 Fire
1ft2 (0.1m2) pan
200 ft (60 m)
Methanol Fire
1ft2 (0.1m2) pan
136 ft (42 m)
Jet A-1 Fire
1ft2 (0.1m2) pan
115 ft (35 m)

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6 Maintenance and Commissioning
Procedure
This maintenance schedule/ commissioning procedure is intended for guidance only. The actual
level of maintenance required will depend on the severity of the operating environment and the
likelihood of damage or the rate of contamination from oil, sea spray, deluge system etc. It is
advisable to regularly review maintenance reports and adapt the maintenance period to the
operating environment.