The Rosemount 975UR flame detector uses an integrated UV/IR dual-sensor to detect hydrocarbon-based fuel and gas fires. The 975UR senses radiant energy in the short wave section of both the ultraviolet and infrared portions of the electromagnetic spectrum. The signals from both sensors are analyzed for frequency, intensity and duration. Simultaneous detection of radiant energy in both the UV and IR sensors triggers an alarm signal. The UV sensor incorporates a special logic circuit that helps prevent false alarms caused by solar radiation .

The 975UR has a wide coverage area and can detect a gasoline pan fire at 66 feet. Response time is typically 3 seconds. Spectral response is UV: 0.185–0.260 μm and IR: 4.4–4.6 μm. The field of view is 100° horizontal and 95° vertical .

The 975UR can perform in the harshest environmental conditions as either a stand-alone unit directly connected to an alarm system or an automatic fire extinguishing system, or as part of a more complex system. Performance can be easily adapted by changing the detector's configuration parameters via HART® or RS-485 communication. It features heated optics to eliminate condensation and icing, and automatic/manual Built-In-Test to ensure continued reliable operation .

Built to be extremely durable and weather-resistant, it operates from -67°F to 185°F (-55°C to 85°C). It meets MIL-STD-810C for environmental conditions, is approved to Safety Integrity Level 2 (SIL 2 - TÜV), and is IP66 and IP67 rated. Hazardous area approvals include ATEX, IECEx, FM and CSA. The 975UR helps you comply with NFPA fire detection standards .