Viking VSF301 User manual

2
Safety and Technical Manual
Rev: 2
Form No. F_020621
VSF301 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_020621 Rev 2
Ref: 2200.5009 Rev: 2.6 ECN:4610

3
Safety and Technical Manual
Rev: 2
Form No. F_020621
VSF301 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
Intelligent Visual Flame Detection.......................................................................................5
2Safety Instructions .....................................................................................................................6
Warnings ............................................................................................................................6
Cautions .............................................................................................................................6
Important Safety Notices ....................................................................................................6
EN 54-part 10 Limitation of use ..........................................................................................8
3Installation .................................................................................................................................9
Detector Enclosure .............................................................................................................9
Mounting & Orientation .......................................................................................................9
Wiring Procedure..............................................................................................................11
0-20mA Output .................................................................................................................12
Relay Mode ......................................................................................................................14
Installation Checklist .........................................................................................................16
3.6.1 Mechanical ................................................................................................................16
3.6.2 Electrical....................................................................................................................17
4System Design Guidelines.......................................................................................................18
Earthing & Screening Requirements.................................................................................18
Power Supply ...................................................................................................................18
RS485 Communications ...................................................................................................18
HART Protocol..................................................................................................................19
Cable Selection ................................................................................................................19
DC Power .........................................................................................................................19
Video ................................................................................................................................20
RS485 Communication.....................................................................................................20
5Application Guidelines .............................................................................................................21
Positioning Requirements .................................................................................................21

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VSF301 Flame Detector
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Detection Coverage..........................................................................................................22
Exposure to Flare Radiation .............................................................................................22
Optical Contamination ......................................................................................................22
Enclosed Areas ................................................................................................................23
Detector Sensitivity...........................................................................................................23
6Maintenance and Commissioning ............................................................................................24
Procedure.........................................................................................................................24
Functional Testing ............................................................................................................26
7Fault Finding............................................................................................................................27
Removal of the Electronics ...............................................................................................27
Replacement of the Electronics ........................................................................................27
Diagnostics.......................................................................................................................27
LED Indication ..................................................................................................................28
Power Fault ......................................................................................................................29
Live Video Images ............................................................................................................29
8Technical Specification ............................................................................................................30
Detector Information .........................................................................................................30
Electrical Specification......................................................................................................30
Mechanical Specification ..................................................................................................31
Environmental Specification..............................................................................................31
Certification and Approvals ...............................................................................................32
Operating Specification.....................................................................................................32
VSF301 Detector Ordering Information.............................................................................33
Detector Accessories and Spares.....................................................................................33
9Appendix A - Acronyms, Terms & Abbreviations......................................................................34
10 Appendix B - Field of View ...................................................................................................35
11 Appendix C - IEC 61508 Failure Rate Data ..........................................................................37

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Safety and Technical Manual
Rev: 2
Form No. F_020621
VSF301 Flame Detector
This document is strictly private and confidential, reproduction without Viking Corporation approval is prohibited. © 2021 The Viking Group Inc.
1 Introduction
The Viking VSF301 is a combined flame detection and video surveillance system utilizing unique
real time video-based flame detection technology developed by Viking. The intelligent visual flame
detection algorithms can discriminate between genuine fire conditions and common false alarm
stimuli.
Detector Features
Live Video
A live color video image is available from each detector; this allows information about the protected
area to be displayed on a monitor in the control room, providing the operator with a visual feedback
of an event, which can reduce response time.
Immunity and Discrimination
The detector is immune to common sources of unwanted alarms such as hot work (e.g., grinding
and welding), hot CO2emissions (such as turbine exhausts) and reflected flare radiation.
Robust and Reliable
The detector has been designed to tolerate extreme environmental conditions experienced offshore
or onshore.
Detection Coverage
The detector is sensitive to fires of n-heptane 1 ft2(0.1m2) at up to 144 ft (44m) within a 90°
horizontal field of view.
Sensitivity
The sensitivity of the detector is preset and no changes in sensitivity are required.
Certified SIL 2 Capability
The detector has been certified IEC 61508 SIL 2.
Intelligent Visual Flame Detection
The detector operates ‘standalone’ or can be integrated within a FM Approved control system.
Detectors are typically located throughout the installation to achieve specific detection coverage and
ensure that site performance requirements are met.
Each detector can provide live video images and fire alarm/fault signaling to the control equipment.
Each detector incorporates within a single unit an imaging device, digital signal processing
hardware, and firmware algorithms to process live video images and recognize flame features.

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VSF301 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.
For European (ATEX) installations IEC/EN60079-14 ‘Electrical Installations in Hazardous Areas’
and IEC/EN 60079-17 ‘Inspection and Maintenance in Hazardous Areas’ should be strictly
observed.
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 minimise 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 energising 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 lens 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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Form No. F_020621
VSF301 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.
Caution
SIL 2 capability is only confirmed for 0-20mA output configuration of the VSF301 visual flame
detector.
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.
(see section 5.2 of this document)
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.
(see section 5.1 of this document).
Extremely dense fog or blizzard conditions could eventually block the vision of the detector. (see
section 5.4 of this document).
For indoor applications, if dense smoke is expected to accumulate at the onset of a fire, mount the
detector on a side wall (approximately 1 meter, 3 feet) down from the ceiling.
The VSF3008 ITEST flame simulator can be used to verify correct detector positioning and
coverage (see section 6.2 of this document).

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VSF301 Flame Detector
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The VSF301 has one sensitivity setting, this is factory set, and no changes can be made to set-up
except by fully trained Viking engineers.
The detector carries out continuous internal hardware diagnostic testing to ensure correct operation
is relayed to the control system. It can also be set to indicate dirty optics if this function is switched
on. The detector should be subjected to a background light level of at least 1 LUX in every 16-hour
period for 1 hour.
The diagnostic test interval – the maximum time taken to execute all diagnostics and act on a
detected hardware fault (via 0-20mA output) is 500ms.
The VSF301 is not designed to annunciate diagnostic failures of signal returns via external wiring.
Control systems and fire panels generally have fault monitoring for such an eventuality.
EN 54-part 10 Limitation of use
The VSF301 is not approved for use in Oxygen-enriched atmospheres.
As the VSF301 responds to visible flame the VSF301 cannot be used in locations where flare
stacks are within its field of view without triggering alarms.
The VSF301 is unable to detect fires that are invisible to the naked eye, such as those using pure
hydrogen, methanol, and sulphur as fuel.
The sensitivity of the VSF301 is reduced by obscurants such as smoke, fog, and other airborne
particulates. The VSF301 may be blinded by extremely dense obscurants.
Arc welding should not take place within 3 feet (1 m) of the VSF301.
The “optical fault” must be disabled for applications where there is no light present e.g., cellar or
chimney stack.

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VSF301 Flame Detector
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3 Installation
The VSF301 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.
Unauthorised 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 and Orientation
Status LED must be below the lens.

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VSF301 Flame Detector
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Figure 2: VSF301 Ceiling Mount
Figure 3: VSF301 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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VSF301 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.
• 0-20mA (source, non-isolated)
• Relay (Alarm & Fault)
Listed below are wiring options dependent on the functional requirements of the detector.
Note: Information below describes how to access RS485 communication by reversing the
polarity of the power when there is no dedicated RS485 pair, or the detector is in HART®
mode. This operation will disable the signal return to the control system whilst enabled. Care
should be taken after using this facility to return the detector to normal operation.

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Form No. F_020621
VSF301 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 Pair Termination
*Tied to spare terminal at control panel to allow RS485 communication with detector. Both
HART® and RS485 cannot co-exist in a detector. When the power to the detector is reversed
RS485 is enabled in this configuration.
Figure 6: 2 Pair Termination
Figure 7: 3 Wire Termination
Figure 8: 4 Pair Termination
VSF301 Terminal
VSF301 Terminal
VSF301 Terminal
VSF301 Terminal

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VSF301 Flame Detector
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Information for wiring in the 0-20mA mode listed in figures 5 to 8 on previous page:
3 Pair Termination
Fully functional detector with continuous video and 0-20mA alarm output with HART®. Reversal of
polarity across terminals 1 & 2 will enable Viking RS485 communication.
2 Pair Termination
0-20mA output only with reversal of polarity across terminals 1 & 2 enabling Viking RS485
communication.
3 Wire Termination
Application where only 3 wires are available. HART® communication is available in this
configuration.
4 Pair Termination
Fully functional detector with continuous video, 0-20mA alarm output and connected Viking RS485
communication.
Viking RS485 communication should only be accessed by trained personnel.
Table 1: Current Level Output Indicators – Default Factory Values
Current Output
Event
< 1.0mA
Power/Detector Fault
1.0mA to 3.0mA
Optical Fault
4.0mA to 7.0mA
Healthy
16.0mA to 19.5mA
Alarm
>19.5mA
Fault (Over-range)
Alarm Relay
A further feature of the VSF301 flame detector when
configured in 0-20mA mode is that an alarm relay is
available if required. The alarm relay contact closes on
alarm and can be employed by connecting to terminals 3
and 13 of the device.
RS485
It is highly recommended to always connect terminals 3 and
4 back to equipment room marshalling cabinet with the use
of a twisted pair cable. This allows access to the RS485
from the safe area.
VSF301 Terminal
Figure 9: 3 Pair Termination with Relay

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VSF301 Flame Detector
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Relay Mode
The following wiring connection diagrams show options for wiring the detector when configured in
relay mode.
Figure 12: 4 Pair Termination
Figure 10: 3 Pair Termination
Figure 11: 2 Pair Termination
VSF301
VSF301
VSF301

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VSF301 Flame Detector
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Information for wiring in relay mode listed in figures 10 to 12 on previous page:
3 Pair Termination
Fully functional detector providing continuous video as well as alarm and fault relays. Reversal of
polarity across terminals 1 & 2 will enable Viking RS485 communication.
2 Pair Termination
Alarm and Fault relay only with reversal of polarity across terminals 1 & 2 enabling Viking RS485
communication.
4 Pair Termination
Fully functional detector with continuous video, alarm, and fault relays as well as permanent Viking
RS485 communication connections.
Viking RS485 communication should only be accessed by trained personnel.
EOL and Alarm resistor values defined by the client and the control system which the detectors are
being integrated into.

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VSF301 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.
3.6.1 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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3.6.2 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.
7
Prepare the cable tails. The cable screens should be cut back to the crotch at the
detector and insulated from contact with the enclosure or any other local earth. The twist
in each pair should be maintained to within 1” (25mm) of the termination. Cable tails
should be 8” (200mm) long.
8
Where plastic junction boxes are used the cable screens (shield) should be maintained
to within 1” (25mm) of the termination and fully insulated.
9
Where unscreened cables are used for panel wiring, then all cables must be suitably
twisted into pairs and video cables should be segregated from other signal sources.
10
All cable screens (shield) should be connected to the local clean earth at the control
panel. The screens and twisted pairs should be maintained to within 1” (25.4mm) of the
terminations.

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Firmware version
Figure 13: VSF301 Information
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.
Earthing & Screening Requirements
It is important to ensure that the system is correctly connected to earth. Incorrect or poor earthing
can adversely affect system operation and may result in poor video image quality.
The detector enclosure is to be connected to a local earth and the detector cable screens (shields)
should be cut back to the crotch and not terminated within the detector. If the detector enclosure
cannot be connected to a local earth, then care should be taken to ensure the cable armor braid
provides a suitable earth or that the enclosure earth stud (external) is separately connected to a
suitable earth point using a single core 12 AWG (4mm2) earth cable.
All detector cable screens should be connected to the local clean earth at the control panel. The
screens (and twisted pairs) should be maintained to within 1” (25.4mm) of the terminations at the
detector, within all junction boxes and at the control panel. Where unscreened cables are used for
panel wiring, then all cables must be suitably twisted into pairs and video cables should be
segregated from other signal sources.
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.
RS485 Communications
RS485 communications can be accessed either directly via the detector specific terminals, or as
previously stated, via terminals A&B (3&4) whilst the power supply polarity is reversed. Using Viking
Simple Apps software, the RS485 channel can be used to view and/or modify detector firmware,
version, configuration or download recorded alarm video from SD card. Contact Viking for Simple
Apps software.

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HART Protocol
Consult factory for further information regarding HART protocol.
Cable Selection
Cable to be used for installation is to be selected with a temperature rating of greater than 77°
Fahrenheit (25° Celsius) 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.
There are several different wiring methods available, as detailed in 3.4 and 3.5 of this manual.
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)
Detector -
Heater off
1
6W
1000
1578
Detector -
Heater on
1
15W
480
800
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
The overall performance and the transmission distance depend on the selected twisted pair cable.
Individually screened twisted pairs offer better electrical immunity.
It is not necessary for the DC power cable to be a twisted pair or individually screened, a 2-core
stranded cable with an overall screen is sufficient. The minimum conductor size is determined by
the cable length, the number of Flame Detectors on each loop and the maximum allowed voltage
drop at the last detector.
To prevent RS485 and Video common mode problems this is limited to a maximum of four volts
(4V) on the negative supply (0V).

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VSF301 Flame Detector
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Video
The video cabling should be a twisted pair stranded cable with an overall screen. Where multi- core
cables are used then individual screened twisted pairs are recommended. The cable should have
the following characteristics:
Table 4: Video Cable Characteristics
Cable
Characteristic
Characteristic
Impedance
Capacitance
Conductor
Resistance
Attenuation
@ 1 MHz
Inductance
Nominal
150R
50nF/Km
--
--
--
Absolute Limit
90R to 150R
100nF/Km
150R
6dB
7mH/Km
The maximum cable length is dependent on the cable manufacturer’s attenuation specification,
which is approximately proportional to conductor size.
The characteristic impedance of a transmission line is a function of the physical dimensions of the
conductor and the permittivity of the dielectric (the insulation), at high frequencies this is
approximately equivalent to:
()=

Equation 1: Characteristic Impedance Calculation
For maximum performance, the video output of the VSF301 is designed for differential twisted pair
operation. For single ended output, a Viking VTP4 or differential to single ended balun should be
used.
RS485 Communication
The RS485 communications cabling should be a twisted pair stranded cable with an overall screen.
Where multi-core cables are used then individual screened twisted pairs are recommended. The
cable should have the following characteristics:
Table 5: RS485 Cable Characteristics
Cable
Characteristic
Characteristic
Impedance
Capacitance
Conductor
Resistance
Attenuation
@ 1 MHz
Inductance
Nominal
120R
50nF/Km
--
--
--
Absolute Limit
90R to 120R
100nF/Km
120R
6dB
7mH/Km
The maximum cable length is dependent on the cable manufacturers’ attenuation specification,
which is approximately proportional to conductor size. The characteristic impedance of a
transmission line is the same as for the video above.
L = Cable Inductance (mH)
C = Cable Capacitance (µF)
Zo = Characteristic Impedance (Ohms)