Inficon 510-010, Technical Handbook

Page: 24 / 52

3-2
Operating the HLD5000
k
in
a
40
e 0
3
.f
m
te
chn
ica
l ha
nd
boo
k
(1
00
7)
3.2 Working with the HLD5000
Provided the HLD5000 has been adapted to the specific requirements of the
application (see Chapter
4 ) and calibrated accordingly, a leak test can be performed
as follows:
Lead the probe tip as close as possible to the locations that are to be tested. If
needed, the tip may even touch the unit under test.
If a welded seam or a joint needs to be tested, the tip of the probe should be moved
no faster than 2.5 cm/s (1 inch/s) across the location which is to be tested. The
distance between probe tip and unit under test should be kept as small as possible.
In the case of probing a specific location, the tip should remain in place briefly (at
least 1 s).
The HLD5000 compares the measured leak rates with the rejection leak rates
(trigger levels) set up as described in Chapter
4.1 . If the measured leak rate exceeds
the rejection leak rate, then more than half of the yellow lamps (LED) on the arc-
shaped display (
Fig. 3-2 /5) will come on and an audible alarm is released.
Due to its working principle (see Chapter 2.1 ) background concentrations in the
environment are suppressed and do not cause an alarm. Refrigerant clouds in front
of large leaks will also be considered a background concentration. Different from the
behavior of its predecessor HLD4000, the HLD5000 will not alarm when only
approaching leaks from a larger distance. Larger leaks will also only be detected
when close to the leak and thus, can be localized reliably.
Notice If you can not guarantee getting close enough to the leak (as described
above) larger leaks may be missed. In this case, please use the flexible
sniffer tip extension (Cat. no. 511-020) which is delivered with the
HLD5000. For this application the extension tip can be cut down to 100 mm
(4 in.) length for easier handling. (see Chapter
1.6.6.3 )
Depending on the measurement mode (see Chapter 4.1 ) the test should be repeated
with the key of the probe pressed to precisely pinpoint the location of the leak or to
double check the rejection leak rate.
Warning
Danger of electric shock.
• Do not touch live parts with the sniffer tip.
• Test samples need to be disconnected from electricity before leak testing.
Caution
U nder all circumstances the intake of liquids which may still be present on the
surface of the test object has to be avoided.
In the case of moist test objects (e.g. condensed water) the use of the water
protection tip is recommended (see Chapter
1.6.6 ).