Merck EMD Millipore NovAseptic, Installation And User Manual

Page: 29 / 32

Problem Possible Causes Solutions
Outer
drive head
scratches the
tank plate
Bent shaft Contact Technical Service.
Bent hole-shaft in gearbox Contact Technical Service.
Drive unit not properly in place Install drive unit correctly.
Particles stuck to the magnets Remove particles.
Deformation of tank plate during
welding
Review instructions for welding the
tank plate and verify tolerances using
appropriate gauges.
Loose outer drive head
Position the outer drive head onto its
lower end position against the shaft and
tighten.
Magnetic
disconnection
of mixing
head
(decoupling)
Incorrect order of addition of
substances, dry running
Review the guidelines under
“Operation/Starting the Mixer.”
Unexpected viscosity/density changes Contact Technical Service.
Incorrect rotational direction of mixing
head
Remove male bearing. Inspect male
bearing and tank plate for damage. If it
is undamaged, reinstall the bearing and
check rotation direction of the mixing
head.
Short acceleration/retardation time Increase the ramp time.
Particles stuck to the magnets Remove particles.
Mixing head
running
eccentrically Male bearing is not properly in place
Remove male bearing. Inspect male
bearing and tank plate for damage. If it
is undamaged, reinstall the bearing and
check rotation direction of the mixing
head.
Bearings worn out
Replace the male bearing and/or repair
mixing head
Abnormal or
“rumbling”
noise
Deep vortex
Reduce speed. Ensure mixing head is
fully covered with liquid at all times.
Cavitation
Investigate: pressure, temperature,
speed
Dry running
Review the guidelines under “Operation
/Starting the Mixer”
Loss of
running
speed
Incorrect incoming power Check the power supply.
Missing phase(s) (AC) Check the fuses.
No signal
from
revolution
counter
Revolution counter unit is incorrectly
mounted on the gear box
Contact Technical Service.
Corroded or damaged socket pins Contact Technical Service.
Cable worn or damaged Contact Technical Service.
NovAseptic
®
GMP ATEX Mixer 29