16 H49 29 53/73 100 Fax: 029 53/73 96 100
DC 2000
PRO
6.
Leakage rates and utility life measurements as per DVGW works-
heet G 624
Leakage rates can be determined in accordance with DVGW worksheet G
624 and the findings documented very easily with the DC 2000
PRO
.
First of all, the line must be sealed and a suitable test plug inserted (see
Section 11). The DC 2000
PRO
must be switched ON and zeroed before it is
connected to the test plug. After the automatic zeroing, press the ± key to
activate the menu item Utility life / Leakage rate. The display now shows the
text “Pipe volume”. This pipe volume can now be determined either automati-
cally or from a graph.
6.1 Automatically determining pipeline volumes
When the ENTER key is pressed at the same time as the text “Pipe volu-
me” appears, the pipe volume can be determined automatically with the DC
2000
PRO
. For a pipe volume up to 100 l a syringe takes a sample volume of
100 ml (Figure 6.2 on the left). Lines with volumes greater than 100 l can be
tested with a manual test pump (163 ml/stroke, see figure 6.2 on the right).
Each test volume must be entered in the DC 2000
PRO
with the ± key and
confirmed with the ENTER key. After a repeated zeroing the DC 2000
PRO
then
shows the text “Pump”. Now the actual sample can be taken with the medical
syringe or the manual test pump up to the set volume. The DC 2000
PRO
then
displays automatically the pipe volume calculated with Equation (3). As soon
as the display no longer changes this value is confirmed with the ENTER key
after which it is used as Vpipe for further determinations of leakage rates in
accordance with G 624.
The measuring principle
When a known sample volume V
sample
is taken from a pipeline system (e.g.
with a medical syringe or a manual test pump), the total volume V
pipe
can be
determined from the resulting pressure change.
For small pipe volumes a medical syringe proves adequate; for larger pipe vo-
Cursorposition:
Utility life/Leaka-
ge rate
6. Leakage rates and utility life measurements
