Sorvall RT/T6000D - Page 133

SORVALL®
Centrifuges
System
Descriptions:
Electrical
6-30.
Motor
Thermal Overload Fuse
Fault
(refer
to figure
6-28)
Embedded
In
the field
windings
of the
motor is
a
thermal
overload
fuse/switch
that
protects
the
motor from
overheating.
The
fuse/switch Is
In
series
with the
windings
and,
when
activated,
opens
the
circuit
up,
removing
power
from
the
drive.
On
early
version
drive
motors,
the thermal
overload device
was a
fuse
link
that.
if
opened
due to
overheating,
rendered
the
drive
unusable.
On
subsequent
models
and
in
current production,
the fuse
link
has been
replaced
with
an automatically resettable temperature switch
that.
when
opened
because
of
a
motor
overtemperature condition,
removes
power
from the drive
and terminates the
run
in
progress.
Once
the
drive
motor
has cooled
down.
the thermal switch
closes and
electrical
contact
can be made
again,
allowing
the
drive
to run
again.
+12Vdc
i.24Vdc
<><—»——»—^QO-!—^-
1^
P/JB-8
P/J15-6
i-
— — —
i
P/J5-15
Motor
Thermal
Fuse
Figure
6-28.
Motor
Thermal Overload
Fuse
6-34