Du Pont SORVALL RC-5 Service Manual page 194

Sorvall®
Centrifuges
Calibration
Procedures11.
Press
SLOW
switch for
ON.
Relay
K407
should energize to
enable the brush
mecha¬nism.12.
Check that door is
open.13.
Set rate at
60,
connect portable tachometer at
the
control
console.14.
Press
both START
and
DOOR switches
at
the same
time.15.
Check
for proper drive motor
operation.16.
Check
for
proper
brush
tension.NOTECheck
that
rotor is rotating at a
60
rate.
Increase rate potentiometer
to0.
Be
sure rotor
does
not
switch to normal
RUN
cycle
with the
door
fullyopen.17.
Set
portable tachometer
to indicate
frequency
readings.18.
Check tachometer for
a speed
indication of
250
Hz/min
with the
chamber door
fullyopen.19.
Rate Control
Calibration:a.
Turn rate control potentiometer
Rl 10
to maximum
limit
by
turning
fully
clock¬wise
facing the back of the
centrifuge.b.
On
P.C.
Assembly
No.
50155,tum potentiometer
R14 to
a
fully
clockwise
posi¬tion
and
stop,
then slowly turn back in a counterclockwise
direction
until
thefirst
fully horizontal position is
obtained.NOTEFor
a fine adjustment, turn potentiometer
R14
in a clockwise direction
toincrease
or counterclockwise direction to
decrease.c.
Press door switch S301;
the
compressor should start
operating.d.
Set timer to the
OFF
position.20.
Close
centrifuge
door.21.
Set
timer to
HOLD
position.22.
Press START switch for
ON.23.
Observe that
transfer point occurs between
170 Hz to 180 Hz when
accelerating.24.
Observe that
transfer point occurs between
110 Hz and
120
Hz during
deceleration.7-11