Performance Considerations - Emerson Rosemount 975UF Reference Manual

Reference Manual
00809-0100-4977
TR CU/EAC
The flame detector is in compliance with the standard TR CU 012/2011 per:
1Ex db eb op is IIC T4 Gb X
Ex tb op is IIIC T96 °C Db X
-55 °C ≤ Ta ≤ +75 °C
or
1Ex db eb op is IIC T4 Gb X
Ex tb op is IIIC T106 °C Db X
-55 °C ≤ Ta ≤ +85 °C
For more details, see TR CU certificate No. TC RU C-US MЮ 62.B05535.
1.5

Performance considerations

1.5.1 Detection sensitivity
Detection sensitivity is the maximum distance at which the detector reliably detects a
specific size of fire and typical type of fuel (standard fire).
Standard fire
Defined as 1 ft.
(2 m/sec).
Sensitivity ranges
The detector has two response levels:
• Warning (Pre-alarm)
• Alarm
The detection distance for the Alarm level is 65 ft. (20 m) from a standard fire.
The detection distance for the Warning level is approximately 10 percent higher than the
Alarm
For some typical ambient conditions, the Zeta parameter as defined in NFPA 72 for the
detector is 0.005 (1/meter).
Note
Zeta parameters may vary significantly with changes in temperature, air pressure,
humidity, visibility conditions, etc.
Rosemount 975UF
2 2
(0.1 m ) n-heptane pan fire with maximum wind speed of 6.5 ft./sec
distance.
Introduction
June 2021
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