0 description, Detcon model dm-434b oxygen sensor pg.3 – Detcon DM-434B User Manual

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1.0 DESCRIPTION

Detcon Model DM-434B, oxygen sensors are designed to detect and continuously monitor O2 in air over the
range of 0-25%. Method of detection is by diffusion/adsorption requiring no moving parts. The sensor
assembly consists of an galvanic air battery cell mounted in a stainless steel housing, a signal conditioning
control transmitter circuit, a terminal board, an explosion proof junction box and a machine fitted rain shield.

1.1 Sensor Technology
The sensor technology is of the two electrode, galvanic metal air battery type cell, which is housed as a
field replaceable plug–in module. The cell is diffusion limited and functions as a direct current generator
proportional to the amount of oxygen adsorption. The sensors are temperature compensated and show
good accuracy and stability over the operating temperature range -4° to +122° Fahrenheit. The sensor is
warranted for one year and has an expected service life of up to two years in ambient air at 20.9% oxygen.

1.2 Control Transmitter Circuit
The 4-20 mA DC control transmitter is equipped with zero and span adjustments accessible through a face
plate allowing one man remote calibration without communication with control room personnel. The trans-
mitter circuit module is plug-in replaceable, via gold plated pins, facilitating easy maintenance and repair.

Detcon Model DM-434B Oxygen Sensor PG.3

Construction of Galvanic Cell

Cathode

Anode

Electrolyte

Solution

Diffusion Barrier

Air Supply

Load

Resistor

T E

TON

SIGNAL

DM-434B

ZERO

FINE

COARSE

0-25%

detcon inc.