1
Introduction
1.1
Overview
The Rosemount 975HR Multi-spectrum Infrared Hydrogen Flame Detector is specifically
designed for the detection of hydrocarbon and hydrogen flames. It detects hydrocarbon-
based fuel and gas fires at long distances with the highest immunity to false alarms. The
detector can detect a gasoline pan fire at 215 ft. (65 m) or a hydrogen flame at 100 ft. (30
m) in less than five seconds.
All Rosemount 975 series detectors include a heated optical window for improved
performance in icing, snow, and condensation conditions.
The operator can easily adapt detection performance to all environments, applications,
and requirements by changing the detector's configuration parameters. Adjusting these
parameters, as well as performing other maintenance and monitoring tasks, is possible by
means of RS-485 based Modbus
®
communication or HART
®
communication (in models
with 0-20 mA output).
The detector enclosure is ATEX certified Exd flameproof with an integral, segregated, rear,
Exe terminal compartment (avoiding exposure of the sensors and electronics to
surrounding environment). Hence the combined approval:
Ex II 2G D
Ex db eb op is IIC T4 G
Ex tb op is IIIC T96 °C Db
(-55 °C ≤ Ta ≤ +75 °C)
or
Ex II 2G D
Ex db eb op is IIC T4 Gb
Ex tb op is IIIC T106 °C Db
(-55 °C ≤ Ta ≤ +85 °C)
The flame detector is designed to operate as a stand-alone unit directly connected to an
alarm system or an automatic fire extinguishing system. The detector can also be part of a
more complex system where many detectors and other devices are integrated through a
common control unit.
Reference Manual
Introduction
00809-0100-4976
June 2021
Rosemount 975HR
7
Legacy
