33
1.1 Flameproof high temperature flammable gas
detector
This version of
Xgard
is a Flameproof high temperature (150°C / 302°F)
gas detector, designed to detect flammable gas present in ambient air, at
concentrations not exceeding the Lower Explosive Limit (LEL) of the
target gas for which it is calibrated.
Xgard
Type 4 operates using
pellistors as part of a 3wire Wheatstone Bridge (WB) circuit, and must be
connected to a suitable control card. The detector is certified
II 2 G
EExd IIC T3, and is suitable for use in Zone 1 and Zone 2 hazardous
areas.
Electrical connections to the detector are made via the terminal block on
the PCB shown below.
Diagram 10:
Xgard
Type 4 dimensioned view
1. Introduction
Xgard Type 4
+SI
+SI G -
M20, M25, 1/2” or
3/4” NPT cable
entry
146
166.3 Overall
Height 111
36 slot CRS to suit M6 or 1/4”
fixings for ceiling mount
196 Overall
Black
White
+ SIG
Red
Internal
grounding
terminal
(earth)
Additional
external
grounding
terminal
(earth)
The
detector
head and
sensor
retainer are
bonded
together
and must
be
replaced as
a unit.
