Rosemount™ 975MR Multi-spectrum Infrared Flame Detector


Rosemount™ 975MR Multi-spectrum Infrared Flame Detector


The Rosemount 975MR multi-spectrum infrared flame detector is based on accurately analyzing the multi-spectral signals by utilizing three separate IR sensors. The 975MR detects fuel and gas fires at long distances. For example, this product will detect a 1 ft2 (0.1m2) gasoline pan fire at 215 ft (65 m) in less than 5 seconds. The 975MR also provides the highest immunity to false alarms and enhanced overall coverage range.


Time Constant / Response
Typically 5 s
Power Supply
Standby: Max. 90 mA (110 mA with heated window)
Alarm: Max. 130 mA (160 mA with heated window)
Communication Protocol
Optional HART® communications on the 0–20 mA analog current (FSK) - used for maintenance, configuration changes and asset management, available in mA source output wiring options.RS-485 Modbus compatible communication link that can be used in computer controlled installations
Ambient Temperature
Operating: -67 °F to +167 °F (-55 °C to +75 °C)
Option: -67 °F to +185 °F (-55 °C to +85 °C)
Storage: -67 °F to +185 °F (-55 °C to +85 °C)
Enclosure Rating
Stainless Steel 316L with electro polish finish
Heavy duty copper free aluminum (less than 1 %), red epoxy enamel finish (not available in FM version)
Stainless Steel 316L with electro polish finish
Detector 4"  x 4.6"  x 6.18"  (101.6 x 117 x 157 mm)
Detector (stainless steel 316L) 6.1 lb (2.8 kg)
Detector (aluminum) 2.8 lb (1.3 kg)
Tilt mount 2.2 lb (1.0 kg)

Ex II 2 G D
Ex de e IIC T5 Gb Ex d e IIC T4 Gb
Ex tb IIIC T96?C Db Ex tb IIIC T106?C Db
(-55?C ≤ Ta ≤+75?C) (-55?C ≤ Ta ≤+85?C)


Class I Div.1, Groups B, C & D
Class II/III Div.1, Groups E, F & G


  • Multi spectrum design - for long distance detection and high false alarm immunity
  • Sensitivity selection - to ensure no zone crossover detection
  • Automatic and Manual Built-In-Test (BIT) - to assure continued reliable operation
  • Heated window - for operation in harsh weather conditions (snow, ice, condensation)
  • Relays (3) for Alarm, Fault, and Auxiliary
  • 0–20 mA (stepped)
  • HART® Protocol for maintenance and asset management
  • RS-485, Modbus compatible
  • High Reliability - MTBF - minimum 150,000 hours
  • Approved to Safety Integrity Level 2 (SIL 2 – TÜV)
  • 5-Year Warranty
  • User Programmable via HART® or RS-485

Documents & Drawings

Training & Services