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➨
Remove the 4 screws affixing the back cov
-
er with a Torx driver T20 to replace the fus-
es. Pay attention to the washers under the
screws.
➨
Pull off front cover carefully. Do not tilt.
➨
Switch off the pump.
➨
Disconnect the electrical power cord
before remov-
ing the covers. After disconnecting from power,
wait
two minutes
to allow the capacitors to discharge.
+
The replacing of the fuse has to be carried out by a
trained electrician.
+
After replacing the fuse, the pump must be checked for
electric safety (see below)! Identify and eliminate the
cause of failure before switching on the pump again.
Replacing the fuse
If the pump does not achieve the ultimate vacuum:
- Whenever the diaphragms and valves have been replaced, a break-in
period of several hours is required before the pump achieves its ulti-
mate vacuum.
- In case of an unusual noise, switch off pump immediately and check
clamping disc positions.
If the specified ultimate vacuum is not achieved, and if this does not
change after the break-in period:
If necessary recheck valve seats and pump chambers.
Checking the ultimate vacuum
➨
After any intervention at the equipment (e.g., repair / maintenance)
the ultimate vacuum of the pump has to be checked. Only if the pump
achieves its specified ultimate vacuum, the pump’s leak rate is low
enough to ensure that no explosive atmospheres will occur in the inte-
rior of the equipment.
