Sorvall RT/T6000D - Page 203

SORVALL®
Centrifuges
RT6000B
and
T6000B
Centrifuges
Serial
Numbers
Below
9101800
12.
Set
the
SPEED
control knob for
maximum
speed
and
adjust
R87
to
3200
rpm
±50
rpm
(with
an
H-
1000B
installed).
If
you
used
an
A-384
Rotor for this
procedure,
adjust
R87
for
6000
rpm
±50
rpm.
13.
At
maximum
speed, use
an
amp
meter to check the
motor current
from
wire
30
on
TB2-5
for 5.75
amps
to
6.00
amps.
14.
Set
the
SPEED
control
knob for
minimum
speed
turning
the dial
counterclock¬
wise (not
to
zero)
and
adjust
R106
for
700
rpm
±50
rpm.
NOTE
Turning
the
SPEED
control
knob to
full
counterclockwise position switches
the
speed
control
off
and
the
rotor
will
not
spin.
15. Repeat step
12.
16.
Calibrate the imbalance detector
(see
paragraph
below).
g.
Imbalance Detector
Calibration
Be
sure
to
note
the
following
points
when calibrating
the
imbalance circuit:
•
Before starting
the calibration
procedure,
note
the threshold
level value
on
the
field
service
report.
After the calibration
process
is
complete,
also note the
final
threshold
value.
•
The
threshold
adjustment must
fall
between
+0.5
Vdc
and
+4.0
Vdc
as
measured
at
I.C.
U4
pin4.
•
Always adjust
the
variable resistor
(potentiometer,
R3)
first.
If
you
reach the
+4.0
vdc potentiometer
limit
and
the
rotor
still
does not
trip,
decrease
the
gap
by
turning
the
setscrew
1/8
turn
clockwise for
increased
sensitivity.
If
you
reach
the
+0.5
vdc
potentiometer
limit
and
the
rotor continues to
trip,
increase
the
gap
by
turning
the
setscrew
1/8
turn counter
clockwise
for
decreased
sensitivity.
•
You
can
decrease
the
imbalance
sensitivity
by
decreasing
the
voltage
level
at
the
threshold
test
point
as
measured
at
I.C.
U4
pin
4.
•
The
foam
insert and rubber boot
affect
the sensitivity
of
the imbalance calibration;
make sure they are
installed.
•
The
rotor must slow
to
100
rpm
or
below before
the
next
run
is started.
•
If
the
calibration
produces
"passing"
results,
but
trips
during deceleration,
the
calibration
needs to
be
continued.
The
rotor
should
not trip
on
deceleration.
1.
For centrifuges
with
serial number
8601094
and
above,
make
sure
that the
set
screw
is
properly
positioned above
the
imbalance detector. Use
a
feeler
guage
to
adjust
the
set
screw
so
that
there
is
a 1.1
mm+0.13/-0.0(0.045 inch+.005/-0.000)
gap
between
the
bottom of
the
set
screw
and
the
imbalance detector
(see
page
5-38).
Rev.
7/93
8-33