Installation

C7015A

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 seal-off adapter 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

fromthephotocelltoa0.125 in. L3.175 mm] diameterorifice is4in. [101.6mm],andfromtheorificetotheflamejunction (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.

TABLE ADIAMEXER OF AREA SIGHTED THROUGH ORIFICE, IN IN.

1.1

1.6 I 2.1

2.6

3.2

TABLE 5-DIAMETEROF AREA SIGHTED THROUGH ORIFICE, IN MM

Fig. 3-4sing orifice plate to restrict detector field of view to intersection of pilot and main flame, or to sniall area of hot refrktory.

	WlTHOUT ORIFICE PLATE				WITH OFilflCE PLATE
PILOT	HOT REFRACTORY	MAIN FLAME	\	PILOT,	HOT REFRACTORY\	MAIN FLAME\
\	\		\