Det-Tronics Eagle Quantum 95-8470-05, Инструкция по эксплуатации

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C. Materials that remove the catalytic metals from the
active element of the sensor.
Some substances react with the catalytic metal
forming a volatile compound. This erodes the metal
from the surface. With sufficient exposure, most or
all of the metal catalyst can be removed from the
surface of the active element of the sensor.
Halogens and compounds containing halogen are
materials of this nature.
Examples:
Chlorine
Bromine
Iodine
Hydrogen Chloride, Bromide or Iodide
Organic halides:
Trichloroethylene
Dichlorobenzene
Vinyl chloride
Freons
Halon 1301
(Bromotrifluoromethane).
A brief exposure to one of these materials can
temporarily increase the sensitivity of the sensor.
This results because the surface of the active
element is increased due to etching. Prolonged
exposure continues the etching process until the
sensitivity of the sensor is degraded, resulting in
shortened sensor life.
D. Exposure to high concentrations of combustible
gases.
Exposure of the sensor to high concentrations of
combustible gases for extended periods of time
can introduce stress to the sensing element and
seriously affect its performance. After exposure to
a high concentration of combustible gas,
recalibration should be performed and, if
necessary, the sensor should be replaced.
The degree of damage to the sensor is determined
by a combination of the type of contaminant, its
concentration in the atmosphere, and the length of
time the sensor is exposed. When a sensor has
been exposed to a contaminant or a high level of
combustible gas, it should be calibrated at the time,
followed by an additional calibration a few days
later to determine whether a significant shift in
sensitivity has occurred.
E. A combination of accessories such as rain shields
and dust covers is not recommended and can
result in slow response to a gas leak.
CALIBRATION GAS
Before calibrating a sensor, check the label on the
calibration gas cylinder to ensure that the correct gas
type and concentration are being used. If a different
gas type is being used for calibration, refer to Det-
Tronics Technical Note No. GTN01 for “K-Factor”
information (Det-Tronics form number 99-1068-02).
V-7 95-8470