MSA AUER Airtester HP, Инструкция по эксплуатации, Страница: 4 / 8

Water vapour detector tubes
20 to 160 mg/m
3
water vapour at a flow rate of 1
l/min and a measuring time of 5 min. (required
sampling volume 5 l) or 5 to 70 mg/m
3
water vapour
at a flow rate of 1 l/min and a measuring time of
10 min. (required sampling volume 10 l).
See also specific instructions for use of the MSA
AUER detector tubes H
2
O-HP.
All values above are based on air not under pressure
and at room temperature resp, normal pressure.
Total amount of sampling air/sampling time are:
min. 68 l / max. 73 l resp. min. 45 min / max. 50 min
5. Operating Instruction
5.1 Preaparing for Measuring
- Clean valve of compressed gas cylinders, resp.
charging connections of compressor with brief
burst of air.
- Connect test device to compressed gas cylinder,
resp. to charging connection of compressor using
adapter.
Chose the adapter suitable for the prescript
maximum pressure of the compressor charging
panel (300 resp. 200 bar). Adjust test device so
that flow meter is vertical (use water level on flow
meter).
5.2 Measuring on Compressed Air Cylinders
- Slowly open cylinder valve
- Set adjusting valve of test device to flow rate of
2 l/min
- Flush device
When the test device is clean and dry flushing for
2 min. sufficient. If the condition of device is not
known, or if during a previous measurement higher
values were found than are permissible according to
EN 12021, flushing at 2 l/min. must be continued.
This must be done until 2 water vapour
measurements, made at an interval of approx. 15
min., give identical results within the permissible
measuring accuracy range. It than can be assumed
that the test device is sufficiently clean for making
measurements.
Liquid water (droplets) can only be removed from the
test device through long flushings with dry, if
necessary warm air.
- Set the air flow required for the measurement
(See para. 4 measuring ranges for detector
tubes).
- For the exact setting of the air flow, the upper
edge of the float must be at the same level as
the marking on the measuring tube (see fig. 2).
- Check, and if necessary adjust air flow setting
after 2 min.
- Observe arrow on detector tube. The arrow
points in the flow direction of the test air,
therefore, after inserting the tube, the arrow must
- Break off the detector tube tips at air exit side
(see fig. 3)
- Put detector tube into the tube holder, inserting
broken-off end tightly into holder side away from
test device.
-
Break off other end of the detector tube (air entry
side) and immediately insert open tube tightly into
other end of detector tube holder (close to test
device). (see fig. 4).
-
Immediately thereafter set timer to the time
designated for the type of detector tube and start
timer.
Note:
After inserting the detector tube the float in the
flowmeter will give a lower reading. Leave the float at
the lower setting during measuring (see fig. 5)
- Wait for timer bell to ring and then close the
adjusting valve of test device immediately.
-
Remove detector tube from holder.
-
Take reading from the printed scale on the tube
5.3 Measuring on compressors
- Switch on the compressor
- Wait until 200 resp. 300 bar are reached
- Switch off the compressor
- Slowly open valve on compressor
- Flush test device as scripted in para. 5.2
- Set required air flow as scripted in para. 5.2
- Check air flow after approx. 2 min. and adjust, if
necessary.
The water content that is measured in air from a
compressor only corresponds to the water content of
compressor gas cylinders simultaneously charged, or
cylinders charged immediately after measuring, if a
pressure retaining valve is built into the compressor at
the exit side of the drying cartridges. A prerequisite,
however, is that the cylinders to be charged are dry.
The pressure retaining valve assures that the
pressure inside the compressor drops only
insignificantly from the maximum pressure of 300
resp. 200 bar, when cylinders are being charged.
With compressor that have no pressure retaining
valve behind the filters, water from the drying
cartridge can be released to the sudden
decompression when the charging connection is
opened. The air has than a higher water content as
was measured on the compressor charging panel.
MSA AUER compressors normally have a pressure
retaining valve.
5.4 Permissable Test Results:
CO Contents max. 15 ppm
CO
2
Contents max. 500 ppm
Oil Contents max. 0,5 mg/m
3
Water contents max. 50 mg/m
3
(rel. to 200 bar)
max. 35 mg/m
3
(rel. to 300 bar
max. 25 mg/m
3
(if sampled from
compressor)
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