Spectrex Rosemount QT-C-311 Quasar 900 Light Source

Spectrex Rosemount QT-C-311 SafEye Quasar 900 Light Source

The Spectrex Rosemount QT-C-311 is an industrial quality, explosion proof, Xenon Flash Infrared Transmitter. The QT-C-311 is specifically intended as the companion light source to the SafEye Quasar 900 Open Path Gas Detection Series. This high intensity light source is designed to give uncompromising performance in the harshest settings, including vessel decks, offshore rigs and petrochemical plants. Used in conjunction with a Quasar receiver, it continuously monitors vast area routes for flammable hydrocarbon gas leaks.

The QT-C-311 uses innovative Differential Optical Absorption Spectroscopy (DOAS) “spectral fingerprint” technology that flashes an ultra-short, high-energy infrared beam over medium-range distances up to 330 feet (100 meters). The highly ruggedised 316L stainless steel enclosure provides comprehensive structural integrity against saltwater corrosion, strong vibration and harsh atmospheric pressures, making it a vital layer of plant and vessel defence.

Model Details:

Manufacturer: Spectrex (An Emerson/Rosemount Brand)

Product Series: SafEye Quasar 900 Series (Quasar 903 System Equivalent)

Model Designation: QT-C-311

Manufacturer Part Number (MPN): QT-C-311

System Configuration Compatibility: Exclusively pairs with the QR-C-111 Receiver to form the Quasar 903 Medium-Range Open Path Detection System.

Key Features

1. Optimised Mid-Range Protection: Projects a precision Xenon flash beam with confidence to travel lengths of 35 to 100 m (115 to 330 ft) to detect large size hydrocarbon gas clouds
2. Dual Enclosure Explosion-Proof: Heavy duty, electro-polished 316L stainless steel construction with a flameproof (Ex d) main housing and an additional safety (Ex e) integrated terminal section.
3. Intelligent Heated Optics. Temperatures below 5°C automatically activate internal window heating elements that clear ice, snow, frost and fogging, so path visibility is never compromised.
4. Extreme Climate Resilience: Fully certified to IP66 & IP68 ingress ratings, designed to survive temporary submersion, high pressure washdown and ambient temperatures from -55°C to +65°C
5. Comprehensive Structural guarantee. Supported by an industry-leading 3-year safety system guarantee and an outstanding 10-year factory warranty on the high-power Xenon flash bulb mechanism.

Installation Process:

1. Vibration and Structural Flex Compensation: Marine bulkheads and structural beams shift under heavy sea states or when machinery is under load. While the Quasar 900 series features a ±5° alignment tolerance, always derate your path layout by roughly 25% if mounting to high-vibration sections. This maintains structural safety margins during rough transits.
2. Optimum Target Alignment: When commissioning the QT-C-311 using the Spectrex telescope kit, tighten your crude horizontal and vertical alignment screws first, then use the simultaneous twin-dial system for fine adjustment. Ensure the crosshairs are centered precisely on the receiver’s sapphire lens before locking down the final tensioning bolts.
3. Salt Crust & Maintenance Protocols: Although the integrated heated optics eliminate misting, salt-spray crystallization can accumulate over time on the sapphire window. Incorporate a monthly optical wipe-down using clean fresh water and a non-abrasive optical cloth into your planned maintenance system (PMS). Avoid harsh chemical detergents which can compromise the anti-reflective lens coatings.
4. Functional Verification Verification: Never bypass manual testing. Use the official Spectrex function check filters (Methane/Ethylene specific) placed directly over the receiver lens to verify that the system moves cleanly from safe operation to warning and full alarm status.