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20901106_EN_MD4_MV2_VARIO_select_V1.0_140818
Fault
Possible cause
Remedy
❑
Vacuum pump
does not start.
➨
Motor overloaded.
Thermal protection has
been triggered.
✔
Allow the motor to cool
down.
Clear error manually:
Unplug pump from the
power supply - Eliminate
cause of error - Switch
pump back on.
❑
No or very little
suction power.
➨
Leak in the suction line
or apparatus.
✔
Check suction line and
apparatus for leaks.
➨
Centring ring at small
flange connection not
correctly positioned.
✔
Check small flange con
-
nection at pump inlet.
➨
Vacuum line too long or
cross-section too small.
✔
Use a shorter vacuum
line with a larger cross-
section.
➨
Condensation in the
vacuum pump.
✔
Allow pump to run for
some minutes with atmo-
spheric pressure at the
inlet to purge.
➨
Deposits inside the
vacuum pump.
✔
Clean and check pump
heads.
➨
Diaphragms or valves
defective.
✔
Replace diaphragms and
valves.
➨
High level of vapor
generated in the pro-
cess.
✔
Check process parame-
ters and settings at con-
troller.
➨
Pump too hot.
✔
Allow pump to cool down.
Determine and eliminate
the cause of overheating.
❑
No display.
➨
Pump switched off.
✔
Switch pump on using
rocker switch.
➨
Power plug not correct-
ly plugged in or pulled
out.
✔
Check power supply and
cable.
➨
VACUU·BUS plug-in
connection or cables
defective or not con-
nected.
✔
Check VACUU·BUS plug-
in connection and cables
to the controller.
➨
Controller switched off.
✔
Switch on controller.
➨
Controller defective.
✔
Contact local distributor.
