Emerson Rosemount 935, Reference Manual

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2.4 Models and types
The Rosemount 935 includes four models with the same detector and different sources.
That gives the detector the ability to get detection at distances of 23 ft (7 m) to 660 ft
(201 m).
Table 2-1: Model numbers and installation distances
Model
number Source Minimum installation
distance Maximum installation
distance
935 T1 23 ft (7 m) 66 ft (20 m)
935 T2 50 ft (15 m) 132 ft (40 m)
935 T3 115 ft (35 m) 330 ft (101 m)
935 T4 265 ft (81 m) 660 ft (201 m)
2.5 Description
The Rosemount 935 comprises two main units:
• Flash infrared source
• Detector
This device detects gases over an open path transmitted from the source to the detector.
2.5.1 Flash source unit
The flash source unit emits infrared (IR) radiation pulses at the rate of two pulses per
second. The pulse width (5-10 µsec) is very powerful. The front of the source has a lens
that collimates the IR beam for maximum intensity. The front window is heated to
improve performance in icing, condensation, and snow conditions.
Reference Manual Technical description
00809-0100-4035 May 2022
Rosemount 935 13