Detcon FP-100 - Manual (Page 5)

Model FP-100
FP-100 Instruction Manual Rev. 0.0 Page 1 of 30
1. Introduction
1.1 Description
Detcon Model FP-100 combustible gas sensors are non-intrusive 4-20mA output sensors designed to detect
and monitor combustible gases in air. Range of detection is 0-100% LEL. The basic sensor assembly consists
of a set of catalytic beads mounted in a stainless steel housing and includes a stainless steel Splash Guard
Adapter. Optionally, the sensor may be installed on an explosion proof junction box and may include a Model
100 Series Display. Other options are available, contact Detcon for more information.
DETCON, INC.
LEL
100 %
FP-100
Model 100
Figure 1 Sensor Assembly with Optional J-Box and LED Display
Catalytic Bead (Pellistor) Sensor Technology
The sensor technology is a poison-resistant catalytic bead type. Catalytic bead sensors show a strong response
to a long list of combustible gases. The sensor is supplied as a matched-pair of detector elements mounted in a
plug-in replaceable module. One bead is a catalytically active detector and the other is a non-active reference
detector. Each detector consists of a fine platinum wire coil embedded in aluminum oxide. A catalytic
mixture is applied to the active detector while the reference detector is treated so that oxidation of the gas does
not occur. The technique is referred to as non-selective and may be used to monitor most any combustible gas.
Detcon catalytic bead sensors are specifically designed to be resistant to poisons such as sulfides, chlorides,
and silicones. The sensors are characteristically stable and capable of providing reliable performance for
periods exceeding 5 years in most industrial environments.
Main Housing Insert
Printed Circuit Board
Gold Plated Pins
Platinum Wire
Construction
of Detector
Bead
Catalyst
Alumina Bead
Catalytic Beads
Figure 2 Sensor Cell Construction