6 Maintenance
B4
1001305a
B4 Density
monitor
W2 Test
connection
Fig. 66
Test connection W2 (view with cover of the contact position indicator removed)
To check the density monitors, remove nut with insert. Gas cannot escape from the breaker with the service
connection open. The service connection W2 is now directly connected with the density monitor, so that after
connection of the filling device W424 the switching points of the density monitor can be checked by regulation of
the SF
6
pressure at the pressure reducer (section 3.1.6
Arc Quenching Medium SF
6
).
6.4.7
Check for Leaks on Operational Circuit-Breaker
The rated pressure of the SF
6
-gas can be found in the table in the section 3.1.6
Arc Quenching Medium SF
6
.
When the filling of the circuit-breaker is completed, all new connections must be checked for leaks. This can occur
with a leak-detector or leak-detecting spray e.g. from Wobst. If neither is available, leaks can also be checked
using soap solution.
If a leak is detected:
WARNING
Release the SF
6
-pressure before working on the screw connections of the gas chamber.
If a leak is discovered, undo the leaking connection and check the sealing surface for damage or foreign bodies.
Then fit a new seal, remake the connection and repeat the leak test.
96
