VACUUBRAND PC 3012 NT VARIO Duo - Manual (Page 141)

page 135 of 145
69
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:
Check hose connectors at pump heads for leaks. 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.
After any intervention at the vacuum sensor the leak rate of the equip-
ment has to be checked.