14
10.5 Laboratory mode
In laboratory mode, the test is carried out without automatic adjustment of the test pressure and without a time limit.
This mode allows the test to be shortened considerably, and is particularly suitable for taking rough measurements.
•
After the self test, this screen appears.
•
You can press the
á
and
â
keys to confi gure the pressure and fl ow rate
manually.
•
You can change the adapter during the test – turn down the fan, change
the adapter and press the ADPT key to change the setting.
•
Press Stop to end the test. Continue as described above.
10.6 Custom airtightness class
A custom leakage fl ow rate U can be selected in the start screen in addition to the standardised airtightness classifi -
cations. This means the tests can be performed in other applications that use different classifi cations, for example in
power plants.
U only appears when the airtightness classes are selected if the value ≠0 is defi ned.
The standardised air leakage classes are:
A
27 l/s m2
B
9 l/s m2
C
3 l/s m2
D
1 l/s m2
•
Press the
ß
or
à
key to move to the letter/digit you want to change.
•
You can use the
á
and
â
keys to enter a custom leakage fl ow rate.
•
Save the value you entered by pressing the
à
key.
•
Alternatively, press the
ß
key to exit.
10.7 Differential pressure
In the idle state after it is switched on, the LT 600 can be used as a differential pressure measuring instrument in order
to monitor a pressure curve over time.
The scale is self-scaling, showing a 120 s block that is continuously updated, overwriting the old test curve.
In this mode, you can use the "-" pressure connection (3) if you want to measure the differential pressure between two
test connections rather than using atmospheric pressure. (E.g. for iris diaphragms, fi lter pressure drops, etc.)
•
Press the PD = 0 key to reset the display.
•
Press the Back key to return to the menu.
•
Press the Stop key to end the test. You can then press Print to print the
graph on the TD 600.
