LOKAL 400 Operating Manual
Page 26
11. Troubleshooting
Correlation leakage detection
– list of possible faults
Fault description
Possible cause
Recommended steps
No signal received from
measurement boxes
1. Measurement boxes are not
switched on or have switched off
automatically due to insufficient
battery capacity
Check the measurement box function and recharge the
measurement boxes, if required
2. Aerials have not been mounted
to central unit
Use the provided aerials for the LOKAL 400 device
3. Aerials have not been mounted
to the measurement boxes
Use the provided aerials for the measurement boxes
4. Excessive distance between the
measurement boxes and the
central unit
Reduce the distance between the particular measurement box
and the central unit
Correlation
result
is
incorrect
1. Incorrect parameter input for the
particular pipe section
Double-check the input on pipe material, pipe length, and pipe
diameter
2. The leakage-borne noise has
been cut off due to incorrect noise
filtering
Double-check the filter setting and repeat the measurement, if
required
3.
Excessive
/
insufficient
amplification of the signal received
Double-check the amplification setting and repeat the
measurement, if required
4. Signal transmitted by the
measurement
boxes
is
not
received, and the Lokal 400 device
is correlating only the background
noise
See
point “ No signal received from the measurement boxes “
No correlation despite
optimal settings and proper
signal reception
1. Correlation is not carried out on
the pipe section to be checked
Double-check the input concerning pipe material, pipe length,
and pipe diameter
Leakage-borne noise is not
audible
1. Type of sensor set is not
appropriate for the pipe section to
be checked
See Chapter 5.1
“Powering-up for correlation“ and „Different
types of sensor“
2. Sensor has come off the fitting /
pipe
Attach the sensor to the fitting / pipe so that it cannot come off
again.
3.
The
pipe
material
as
documented does not comply with
the actual pipe material (plastics)
Sound travels poorly on plastic pipes. In this case it is
recommended to check the particular pipe section with so-called
hydrophones
Acoustic leakage detection
– List of possible faults
No noise audible via the
headphones
1. Microphone or headphones not
connected properly
Double-check the plug-in connections between the connected
accelerometer and the headphones / the central unit.
2. Inappropriate filter settings
Choose a wide frequency range, e.g. 50 to 2,000 Hz and then
make a clearly audible noise such as scratching or switching on
a radio.
If, as a consequence of your noise, fluctuating numerical bar
indications are displayed and the headphones provide clear
noises, this indicates that both the headphones and the
microphone work properly.
Repeat your original measurement and adapt the frequency
range to the measurement situation.
3. Defective cable between the
microphone and the central unit
Double-check the plug-in connections between the connected
microphone and the LOKAL 400 device.
Replace the cable and check the function again.
4. Defective cable between the
headphones and the central unit
(in this case, the level indicator
shown in the display works
properly !)
Double-check the plug-in connections between the connected
headphones and the LOKAL 400 device.
Connect another set of headphones to the device and check the
function again.
5. Memory settings
If the troubleshooting steps described so far have not been
successful, delete the contents of the parameter memory at
”Clear memory
" in the
Settings
menu
.
If there is still no noise
