Teledyne 2240 – Portable Handheld Hydrogen Leak Detector, 2nd generation - Manual (Page 3)

Page 5 of 26 M2240 R0
Table of Contents
SECTION PAGE
i. IMPORTANT NOTICES ..................................................2
ii. Introducing the
2240....................................................6
1. 2240 General Specifications ........................................7
2. 2240 Functions and Features .......................................9
3. 2240 Component Identification..................................10
4. Preparing 2240 for Operation ....................................11
5. 2240 Operation ..........................................................14
6. Configuring the 2240.................................................17
7. Hydrogen Sensing Considerations ...................................21
8. Charging the
2240 Battery .........................................23
Contact TELEDYNE...........................................................26
Page 6 of 26 M2240 R0
ii. Introducing the 2240
The
2240 system consists of a proprietary control system
monitoring inputs from the TELEDYNE Wide Range
Hydrogen Sensor® or WRS. This sensor receives inputs
from two sensing devices. The first device is a hydrogen
sensing capacitor (HCAP). The HCAP sensor is used for
sensing low levels of hydrogen 50 ppm to 10,000 ppm. The
second device is a hydrogen-sensing resistor (HRES). This
device contains a thin film of palladium-nickel deposited on
a silicon substrate and acts like a variable resistor in the
presence of hydrogen. The change in resistance is used to
generate a signal that is proportional to the hydrogen
concentration. This device is used to sense hydrogen from
10,000 ppm to 100%. The
2240 interprets the signals
from both devices and displays an approximate hydrogen
concentration to the operator.
NOTE: The indicated concentration is an
approximate value and should not be used as
an analytical measurement.
It also generates an analog signal in direct proportion to the
displayed value that can be interpreted by an external
monitoring/control system. Since palladium only behaves in
this manner with hydrogen, there is no cross-sensitivity of
the sensor with any other elemental or compound gas.
In addition to the Pd/Ni thin film, the sensor includes a
temperature sensor and an on-board heater. Using these, the
2240
maintains the sensor substrate at a constant
temperature. This elevated, controlled temperature assures
that sensor operation is unaffected by ambient temperature.
Also, the
2240
will sense hydrogen in air while being
held in any position.