The FIREYE 45UV5-1000 is a discrete, ultraviolet (UV) self-checking flame scanner designed for demanding industrial burner and boiler applications. When paired with compatible FIREYE controls such as the 25SU3 and 25SU5 amplifiers, it provides reliable flame presence monitoring, fast flame failure detection, and continuous self-diagnostics to improve combustion safety and system uptime.
Its rugged construction, wide operating temperature range, and ability to discriminate real flame UV from background radiation make it a solid choice for power plants, large industrial furnaces, incinerators, and process heaters burning common fossil fuels.
Key Technical Data for FIREYE 45UV5-1000
| Parameter |
Value / Specification |
Notes |
| Model |
FIREYE 45UV5-1000 |
45UV5 series self-checking UV flame scanner |
| Flame sensing technology |
Ultraviolet (UV) “UV-eye” detector |
Gas-filled UV-sensitive tube with electrode pair |
| Self-checking method |
Electromagnetic shutter, periodic interruption |
Allows the control to verify scanner and signal integrity |
| Supply / shutter voltage |
120 VAC |
For use with designated FIREYE controls |
| Frequency |
60 Hz |
Matched to North American mains frequency |
| Compatible controls |
25SU3, 25SU5 burner controls / amplifiers |
Discrete flame safeguard systems |
| Connection / mounting |
1" NPT thread |
For mounting to a sight pipe on the burner front |
| Housing material |
Die-cast aluminum |
Industrial, corrosion-resistant body |
| Lens type |
Quartz planoconvex lens |
Increases sensitivity versus flat glass |
| Overall dimensions |
Approx. 4 in OD x 8.5 in length |
Compact inline form factor |
| Operating temperature range |
-40 to 200 °F (-40 to 93 °C) |
Suitable for harsh burner front environments |
| Typical fuels monitored |
Natural gas, coke oven gas, propane, methane, butane, kerosene, light oil, diesel |
UV-emitting fossil fuel flames |
| Approvals / certifications |
FM, DIN, other regional approvals (per datasheet) |
For use in approved burner management systems |
| Application type |
Single- or multi-burner industrial installations |
Boilers, furnaces, incinerators, process heaters |
How the FIREYE 45UV5-1000 Works
At the heart of the 45UV5-1000 is a sealed, gas-filled UV detector tube designed to respond only to a specific band of ultraviolet energy emitted by common fossil fuel flames. When UV from a flame strikes the tube, the gas becomes conductive and produces short, discrete current pulses—often called “avalanches”. A strong, stable flame produces a high frequency of pulses, while a weak flame yields fewer pulses. When the flame is completely lost, the pulses stop, aside from very rare pulses caused by background radiation that the system is designed to ignore.
These pulses are transmitted to a compatible FIREYE control (such as 25SU3 or 25SU5). The control interprets the pulse frequency as flame intensity and uses that information to energize or de-energize the flame relay. In practical terms, that means:
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Continuous, real-time verification that a valid flame is present.
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Rapid flame-failure detection for safe shutdown.
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A clear distinction between genuine burner flame and spurious UV sources.
Self-checking shutter mechanism
A key feature of the 45UV5-1000 is its internal electromagnetic shutter. At regular intervals, this shutter physically blocks the optical path between the flame and the UV detector. During this brief closed period, the control expects the flame signal to disappear. When the shutter opens again, the signal must return. If either condition is not met, the control recognizes a scanner or circuit fault and can lock out the system.
This built-in self-checking cycle is essential for continuously fired burners where long operating intervals can hide component failures unless the system actively tests itself.
Design Features That Support Industrial Reliability
The 45UV5-1000 combines optical performance with robust mechanical design:
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Rugged die-cast aluminum housing
The scanner body is built from die-cast aluminum with high-temperature, oil-resistant gaskets to keep dust, moisture, and combustion by-products away from the internal electronics.
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Quartz planoconvex lens
The front lens is made from UV-transmitting quartz, shaped as a planoconvex lens to concentrate incoming UV onto the detector. This geometry can significantly increase sensitivity compared with flat windows, especially on larger burners or longer sight paths.
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Wide ambient temperature range
With an operating range from -40 to 200 °F, the 45UV5-1000 is suitable for outdoor installations in cold climates and for hot burner-front compartments, provided basic installation guidelines and purge air requirements are respected.
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1" NPT mounting
The standard 1" NPT thread makes it straightforward to install the scanner on a properly positioned sight pipe. The mechanical arrangement described in the datasheet allows the housing to be hinged and rotated, simplifying alignment and lens cleaning.
Typical Applications and Fuel Types
The FIREYE 45UV5-1000 is designed specifically for fossil fuels that emit strong UV components in their flame:
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Natural gas and methane
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Coke oven gas and other process gases
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Propane and butane
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Kerosene and light petroleum distillates
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Light fuel oils and diesel fuels
Typical application scenarios include:
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Utility and industrial boilers with continuous or semi-continuous firing
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Large process heaters and refinery furnaces
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Incinerators and waste-to-energy plants
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Combustion systems using FIREYE 25SU3/25SU5 control platforms
For steam-atomized heavy oil or pulverized coal, FIREYE generally recommends infrared (IR) scanners instead of UV, due to different spectral characteristics of those flames.
Installation and Integration Considerations
To get reliable operation from the 45UV5-1000, a few key points should be respected:
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Correct sighting
The scanner should be aimed so that its line of sight intersects the burner flame at an angle, rather than looking straight down the burner axis. This geometry improves discrimination between the monitored burner and neighboring flames or background ignition sources.
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Proper sight pipe and mounting
Use a rigid sight pipe with appropriate insulation and a 1" NPT connection. The housing’s hinge and rotation features allow fine adjustment and regular lens cleaning without disturbing the pipe.
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Purge air
The series supports purge air through a smaller threaded connection in the housing or sight pipe (as outlined in the generic 45UV5 documentation). A moderate flow of clean, dry air across the lens helps prevent soot and dust buildup, particularly on heavy-duty burners and dirty fuels.
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Compatible control and wiring
The scanner must be wired to approved FIREYE controls (25SU3/25SU5 in the case of 45UV5-1000). The system expects the characteristic pulsed signal and shutter interruptions, so using non-sinusoidal power or incompatible amplifiers can damage the scanner or cause unreliable operation.
Advantages of the FIREYE 45UV5-1000 in Modern Combustion Systems
Choosing the 45UV5-1000 for a burner monitoring project gives several practical benefits:
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Continuous self-checking without external test mechanisms
Internal shuttering and electronics checking allow the burner management system to verify scanner health during normal firing, without manual testing or external mechanical devices.
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Strong discrimination between real flame and background
The UV detector focuses on short-wavelength emissions that do not pass through regular glass and that are not generated by refractory glow, hot brickwork, or most ambient light sources. This minimizes nuisance flame signals.
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Proven compatibility with FIREYE safety platforms
The 45UV5-1000 is part of a mature ecosystem of scanners and controls that have been used for decades in heavy industrial combustion, with detailed documentation, wiring diagrams, and application support available.
-
Mechanical robustness for long service life
The die-cast body, quartz lens, and high-temperature gaskets are built for harsh boiler-room conditions, reducing downtime due to mechanical damage or contamination.
In short, the FIREYE 45UV5-1000 UV self-checking flame scanner is a dedicated, field-proven device for reliable flame detection on fossil-fuel-fired equipment. When correctly installed and paired with the appropriate FIREYE control, it delivers the combination of safety, diagnostic capability, and long-term stability that modern burner management systems require.
