What Is a Fireye InSight Scanner?

The Fireye InSight series is a family of integrated flame scanners — meaning the sensor, amplifier electronics, safety relay, and flame switch function are all built into a single compact head that mounts directly at the burner front.

Traditional setups require a separate remote amplifier in a control panel. InSight eliminates that entirely, reducing wiring complexity, cutting signal degradation over long cable runs, and simplifying installation and service.

All InSight models share a common platform foundation that makes them one of the most specified integrated flame detection solutions in industrial boiler and burner applications:

24 VDC Powered Consistent across the entire InSight family — no model-specific power supply requirements.
Electronic Self-Checking No mechanical shutter required. Continuous monitoring with built-in self-diagnostics.
4-20 mA Analog Output Real-time flame intensity signal for your BMS or PLC — tune alarm setpoints precisely.
Flame Flicker Modulation Measures the natural flicker of live combustion to discriminate true flame from ambient radiation.
Adjustable Thresholds Independently set flame relay ON/OFF thresholds at the scanner for your specific application.
Purge Air Compatible Standard 3/8″ threaded or 1″ Y-fitting connections. Typical purge: 4 SCFM under normal conditions; up to 15 SCFM for high-ash fuels or elevated ambient temperatures.

Not Sure Which Model You Need?

Our team has been specifying Fireye equipment since 1967. Tell us your application and we'll get you to the right part number fast.

Get Expert HelpCall (901) 458-2000
Fireye InSight flame scanner in active service on industrial boiler burner
Fireye InSight scanner in active service — integrated directly at the burner front on an industrial boiler.

UV, IR, or Dual Sensor — What's the Difference?

Before diving into specific models, it's important to understand the sensor technology — because this is the first decision that narrows your selection.

UV Sensor

Ultraviolet

Detects the high-energy UV light produced during active combustion. Extremely fast-responding and highly selective — hot refractory walls and adjacent burner radiation won't trigger a false flame-on.

Best for Gas burners · Clean fuel applications · Environments requiring immunity from refractory radiation · Single-burner or low-interference setups
IR Sensor

Infrared

Detects heat radiation from combustion. Performs reliably in dirty, dusty, or contaminated environments where UV signal may be attenuated by a fouled sight glass or high-particulate fuel.

Best for Oil & heavy fuel burners · Dusty/dirty environments · Applications with lens contamination risk · Fuels with weak UV signature
Dual UV + IR

Dual Sensor

Both sensors in a single head. Program to use UV only, IR only, or a combined logic — maximum discrimination flexibility. Essential for multi-burner applications where cross-flame interference is a real concern.

Best for Multi-burner boilers · Variable fuel operation · Difficult discrimination environments · Applications needing maximum detection confidence

Fireye InSight Models — Complete Breakdown

Here's every current and in-service InSight scanner, what makes each one distinct, and exactly when you'd choose it over the others.

InSight I Series
Fireye 95DSS2
The Proven Workhorse
Dual UV + IRLegacy / In-Service

The 95DSS2 is the original InSight dual-sensor scanner — the model that set the template for integrated flame detection across thousands of industrial boilers and burners. It houses both UV and IR solid-state sensors in a single head, with programmable sensor selection during commissioning.

Fireye officially classified first-generation InSight I models as obsolete as of February 2020, but the enhanced 95DSS2E variants remain widely available and are still routinely specified for replacement and retrofit work on existing installations. If you have a 95DSS2 in service, the 95DSS2E is your closest direct swap.

Choose the 95DSS2 when: You're replacing an in-service unit and want a like-for-like swap, your system is already wired and programmed for this platform, or your application doesn't require the enhanced I/O or certifications of newer generations.

Sensor TypeDual UV + IR
Flame Relays1 Flame + 1 Fault
Analog Output4-20 mA
Power24 VDC
SIL RatingNot Rated
StatusLegacy (Gen 1 Obs. 2020)
Need a 95DSS2 or compatible replacement?Request a Quote →
InSight II Series
Fireye 95DSS3
The Enhanced Dual Scanner
Dual UV + IRActiveSIL 3 Certified

The 95DSS3 InSight II is a meaningful step up from the 95DSS2 — carrying forward the proven dual UV/IR platform with key enhancements that matter in demanding applications. The biggest upgrade: two independent internal flame relays instead of one, plus two 4-20 mA analog outputs. This makes it ideal for applications requiring separate pilot and main flame monitoring from a single scanner head.

The 95DSS3 holds multiple worldwide safety agency approvals (FM, UL, CSA, CE, and more), making it the right call for international projects. It supports an attached keypad/VFD display or an optional infrared remote for programming — a practical advantage when the scanner is in an awkward, elevated, or tight mounting position. CEX and WICEX variants provide internal terminal blocks for conduit wiring installations.

Choose the 95DSS3 when: You need dual-relay flame logic for pilot and main flame monitoring, you're working on international or export projects requiring CE/ATEX approvals, you want the strongest cross-flame discrimination for a multi-burner installation, or you're upgrading from a 95DSS2 and want improved I/O and certifications.

Sensor TypeDual UV + IR
Flame Relays2 Flame + 1 Fault
Analog OutputTwo 4-20 mA
DisplayVFD + IR Remote Option
ApprovalsFM, UL, CSA, CE + More
StatusActive
Ready to order the 95DSS3?Request a Quote →
InSight Series 4 — Current Generation
Fireye 95UVS4
The UV Flagship
UV SensorCurrent / LatestSIL 3 Rated

The 95UVS4 is Fireye's current-generation flagship UV integrated flame scanner. The Series 4 platform represents a significant jump in processing capability — the scanner integrates detection, amplification, safety determination, and flame switch functions into one head using a fully advanced microprocessor architecture.

During commissioning, the scanner automatically measures flame flicker across 21 selectable modulation frequencies and locks in the optimal frequency and sensor gain for your specific flame. This auto-configuration dramatically reduces setup time and eliminates the guesswork of manual frequency selection. Remote communication and diagnostics are available via the optional Fireye Explorer PC software (CU-109) over RS485 — useful for multi-scanner installations, logging, and remote setpoint review from a control room.

The Series 4 carries a SIL 3 (Safety Integrity Level 3) rating — critical for applications governed by IEC 61511 or facilities building SIS (Safety Instrumented Systems) that require documented functional safety ratings.

Choose the 95UVS4 when: You're specifying new installations on natural gas-fired burners, your application requires SIL-rated flame detection for a safety instrumented system, you want the latest platform for long-term parts and support alignment, or remote Modbus communications via Fireye Explorer software is needed for your BMS integration.

Sensor TypeSolid-State UV
Frequencies21 Modulation Choices
Analog Output1 (4-20 mA)
Auto-ConfigurationYes + Manual Override
SIL RatingSIL 3
Remote ConfigFireye Explorer (RS485)
Spec the 95UVS4 on your next project?Request a Quote →
InSight Series 4 — Current Generation
Fireye 95IRS4
The IR Flagship
IR SensorCurrent / LatestSIL 3 Rated

The 95IRS4 delivers the full Series 4 platform in an infrared configuration — everything the 95UVS4 offers, built for environments where UV detection is compromised. Oil-fired burners, kilns, process furnaces, and any installation where dust, particulate, or lens contamination can attenuate UV signal are where the 95IRS4 earns its place.

Infrared sensing cuts through the environmental conditions that defeat UV scanners. Even with moderate sight glass contamination or high-particulate fuel combustion, the IR sensor maintains reliable flame detection — reducing nuisance trips and callbacks. The solid-state IR sensor, combined with Series 4's advanced microprocessor discrimination, gives you the best IR detection performance Fireye currently produces.

All Series 4 advantages carry over: 21 modulation frequency selections, auto-configuration with manual override, SIL 3 safety integrity rating, and remote communication capability via Fireye Explorer PC software over RS485.

Choose the 95IRS4 when: You're firing on oil, heavy fuel, or a combination fuel that produces a weak UV signature, your environment is dirty or dusty enough to compromise UV sensing, you need SIL 3-rated IR detection for a safety instrumented system, or you're standardizing new installations on the Series 4 platform and IR is the right sensor type for your fuel.

Sensor TypeSolid-State IR
Frequencies21 Modulation Choices
Analog Output1 (4-20 mA)
Auto-ConfigurationYes + Manual Override
SIL RatingSIL 3
Remote ConfigFireye Explorer (RS485)
Best FuelOil / Heavy / Dirty Apps
Oil-fired or heavy fuel application? 95IRS4 is likely your scanner.Request a Quote →

Side-by-Side Comparison

Use this table to quickly compare capabilities across all four InSight models. For selection help on a specific application, call our team at (901) 458-2000.

Feature95DSS295DSS3 (InSight II)95UVS4 (Series 4)95IRS4 (Series 4)
GenerationInSight IInSight IISeries 4Series 4
Sensor TypeDual UV + IRDual UV + IRUV OnlyIR Only
Flame Relays1222
4-20 mA Outputs1211
Modulation FrequenciesLimited21 Choices21 Choices21 Choices
Auto-ConfigurationBasicYesYesYes
Remote / Wireless Config—IR Remote HandheldFireye Explorer (RS485)Fireye Explorer (RS485)
SIL Capability—✓ SIL 3✓ SIL 3✓ SIL 3
Multi-Burner DiscriminationGoodExcellentGood (UV)Good (IR)
Oil / Heavy Fuel✓ (IR mode)✓ (IR mode)Not Recommended✓ Ideal
Natural Gas✓✓✓ Ideal✓
International ApprovalsLimitedFM, UL, CSA, CE, MoreFM, UL + MoreFM, UL + More
Current ProductionLegacyActiveCurrent / LatestCurrent / Latest

Application Selection Guide

Match your real-world situation to the right InSight model. When in doubt, our application engineers are a phone call away.

Natural Gas Boiler — Single Burner

Clean combustion, strong UV signal, no adjacent-burner cross-flame concern. UV selectivity prevents false flame-on from hot refractory.

→ 95UVS4 (Series 4)

Oil-Fired or Heavy Fuel Burner

Oil flames produce weaker UV signatures and more particulate that coats sight glass. IR cuts through contamination for dependable detection.

→ 95IRS4 (Series 4)

Multi-Burner Boiler or Header

Adjacent burner radiation risks cross-flame false signals. Dual UV+IR with programmable logic gives the strongest per-burner discrimination available.

→ 95DSS3 (InSight II)

SIS / SIL-Rated Safety System

NFPA 85, IEC 61511, or facility requirements demand documented SIL 3 performance. The 95DSS3 (InSight II), 95UVS4, and 95IRS4 all carry SIL 3 certification — select based on sensor type and I/O requirements.

→ 95DSS3, 95UVS4, or 95IRS4

Replacement of Existing 95DSS2

System is functional — you need a reliable swap without a full panel rewrite. 95DSS2E is like-for-like; 95DSS3 is the recommended upgrade path.

→ 95DSS2E or 95DSS3

Multi-Scanner or Control Room Integration

Managing multiple scanners from a central location or need remote diagnostics and setpoint logging. Series 4 supports Modbus RS485 communications via Fireye Explorer PC software (CU-109), connecting up to 32 scanners on a single loop.

→ 95UVS4 or 95IRS4 (with Fireye Explorer)

International / Export Project

EU, UK, or other markets requiring ATEX, IECEx, or UKCA marked equipment. InSight II holds the broadest portfolio of international certifications.

→ 95DSS3 (InSight II)

Kiln, Dryer, or High-Particulate Process

Kilns and dryers put heavy particulate loads on sight glass optics. IR detection maintains signal integrity between cleaning intervals where UV would degrade.

→ 95IRS4 or 95DSS3 (IR mode)

Ready to Order or Need Spec Help?

We stock Fireye InSight scanners and can confirm the right model, cable, and mounting hardware for your application today.

Request a Quote(901) 458-2000

Frequently Asked Questions

Does the Fireye InSight scanner require a separate amplifier?
No — that's the defining feature of the InSight series. The amplifier and flame relay electronics are built directly into the scanner head, eliminating the need for a rack-mounted remote amplifier. The scanner outputs a direct flame-on/flame-off relay signal and a 4-20 mA intensity signal that ties straight into your BMS or PLC.
What's the difference between the 95DSS2 and 95DSS3?
The 95DSS3 (InSight II) upgrades from the 95DSS2 with two independent flame relays instead of one, two 4-20 mA outputs instead of one, a VFD display with optional infrared remote programming, 21 modulation frequency selections, and significantly broader worldwide safety agency approvals including CE and ATEX. If you're upgrading an existing 95DSS2 system, the 95DSS3 is the recommended path.
Can I use the 95UVS4 on an oil-fired burner?
It's not recommended. Oil and heavy fuel combustion produces weaker UV emissions and more particulate that can coat and degrade the UV sensor's sight glass over time. For oil-fired applications, the 95IRS4 (infrared) is the correct Series 4 choice — it's built to cut through the environmental conditions that challenge UV detection.
What does SIL-capable mean on the InSight scanners?
SIL (Safety Integrity Level) is a performance rating under IEC 61508 / IEC 61511 for safety instrumented systems. A SIL-rated scanner can be incorporated into a Safety Instrumented System (SIS) with a documented functional safety rating. This is increasingly required by insurance, regulatory, or internal safety standards on industrial combustion applications — particularly where NFPA 85 compliance is involved. The 95DSS3 (InSight II), 95UVS4, and 95IRS4 all carry SIL 3 certification. The original 95DSS2 is not SIL rated. If SIL 3 documentation is required for your project, confirm the specific certification paperwork with your Fireye representative at the time of order.
How do I select the right modulation frequency?
On InSight II and Series 4 models, the scanner can automatically select the optimal modulation frequency during commissioning — it measures your flame's natural flicker pattern and locks in the best frequency for discrimination. You can also set it manually with full override control. The original 95DSS2 has limited frequency selection by comparison. If you're commissioning a tight discrimination application, Series 4's 21-frequency auto-tune is a significant time-saver.
Memphis Control Center stocks Fireye InSight scanners?
Yes — Memphis Control Center is an authorized Fireye distributor with InSight scanner inventory on hand and access to the full product line. We ship same-day on in-stock orders placed by 2 PM CT. Call us at (901) 458-2000 or use the quote request form and our team will confirm availability and get your order moving.