Gas Sampling; Maintenance, Calibration And Gas Testing - Linde G-TECTA SG Operating Manual

Gas Sampling

To take a sample of a gas in a confined space or
where there are unknown levels of gas present
using G-TECTA SG, the flow sample method can
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be used. A flow cap and hose must be fitted over
the sensor on the front of the instrument and an
aspirator bulb fitted onto the other flow cap nozzle.
Note: A flow cap and a 2 metre length of hose
is included in the box with your G-TECTA
instrument. The aspirator bulb and hose (Article
Numbers ASGTAK2 or ASGTAK3) is an additional
accessory.
1. To fit the flow cap, clip the flow cap over the
sensor on the front of the instrument until it
is tightly fitted into place.
2. Attach the sampling hose onto one of
the nozzles.
3. Attach the aspirator bulb onto the
other nozzle.
4. Check the aspirator bulb is attached correctly
by covering the end of the bulb and by
squeezing it gently. If there are no leaks,
the aspirator bulb should remain deflated
for a few seconds.
5. Squeeze the aspirator bulb once per second to
create a steady flow of air into the instrument.
We recommend the operator squeezes the
aspirator bulb at least 10 times (using the 2
metre hose supplied). Longer lengths of hose
and metal probes can be purchased. For
additional lengths of hose, we recommend
that the aspirator bulb is squeezed once for
every additional 30cm of hose to enable the
gas sample to reach the sensor. Continue to
squeeze the bulb for an additional 45 seconds,
or until gas readings stabilise.
6.
WARNING

sampling only provides continuous gas readings
for the area in which the hose or probe is located
and when the aspirator bulb is being continuously
squeezed. Each time a new gas reading is required,
the aspirator bulb must be squeezed a sufficient
number of times to bring a fresh sample and a
stabilised reading to the sensor.
Maintenance, Calibration
and Gas Testing
Cleaning
Ensure the G-TECTA
SG
®
and sensor filter remain free from dirt build up.
Regularly wipe over your G-TECTA
damp cloth and inspect the sensor filter for dirt
or damage.
Gas (bump) testing
The atmosphere in which G-TECTA
are used can have lasting effects on the sensors.
Sensors may suffer losses in sensitivity leading
to degraded performance if exposed to
certain substances.
The Linde Group recommends a bump test each
time the G-TECTA
for use. As a minimum, a monthly bump test is
required to confirm sensor operation.
A test gas of known composition (compatible
with the settings on the instrument sensor
module) needs to be applied,to verify sensor
response and alarm function.
Note: Please see The Linde Group data sheet
"Gas Detector Calibration Frequency" for further
advice on bump testing and calibration.
To remove the flow cap, gently unclip the
cap from the sensor and lift it away from
the instrument.
Manual aspirator remote
SG display, operator button
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SG instrument is used or issued
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11
UK
SG unit with a
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SG instruments
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