Table 4 -Diameter Of Area Sighted Through Orifice, In In; Table 5-Diameter Of Area Sighted Through Orifice, In Mm; Fig. 3 -Using Orifice Plate To Restrict Detector Field-Of-View To Intersection Of Pilot And Main Flame, Or To Small Area Of Hot Refractory - Honeywell C7015A Product Manual

INSTALLATION
INSTALLING AN ORIFICE PLATE
AnorificeplatewithahexagonalorificediameterofO.125
in. [3.2 mm] is available for the C7915A Infrared Flame
Detector. The orifice can be mounted in front of the cell in the
adapter
seal-off or in a standard 314 in. coupling. (Refer to Fig.
1.)
The size of the sighted area at various distances can be
determined from Table 4 or 5. For example, if the distance
6
Fig. 3-4sing orifice plate to restrict detector field of view to intersection of pilot and main flame, or to
PILOT
\
OF AREA SIGHTED THROUGH ORIFICE, IN MM
HOT REFRACTORY MAIN FLAME
(or refractory) is 36 in. [914.4 mm], the dieter of the
sighted area is 2.4 in. [70 mm].
Fig. 3 shows how a typical orifice plate restricts the view
of a small area around the flame junction.
1.1 1.6
PILOT, HOT REFRACTORY\
6
2.1 2.6
MAIN FLAME\
3.2