Du Pont SORVALL RC-5 Service Manual page 191

Calibration Procedures
Sorvall®
Centrifuges6.
Repeat steps
2
through
5 until
-3°C
set-pointer is
5°C
below the temperature
re¬corded
in
step
4.1.
Temperature
Control
Set-Points Potentiometer
(R42 and
R43)This
procedure
establishes the
RUN
and
HOLD
mode compressor
set
points.1.
Set the
main
circuit breaker to
ON.2.
Install an
SS-34
rotor and latch the chamber
door.3.
Set the RUN
mode
set
point to
5°C
below indicated
temperature.4.
Set the HOLD
mode set point
to
5°C
above
Indicated
temperature.5.
Connect the dc voltmeter to
TP-1
(-) and the collector of transistor Q15
(+).
Meterindication
should be greater than 4.5
Vdc.6.
Move the HOLD set-pointer toward the back
temperature
indicator pointer until
theHOLD
pointer
is
exactly over
the black
temperature
indicator pointer. The
voltageshould
switch
to lower
than
1.0
Vdc.7.
If the
voltage change occurs above or
below the
set-pointer,
align the
set-pointerwith
the black indicator and
adjust potentiometer
R42
accordingly.8.
Set the
SPEED
control to
1000
rpm.9.
Be sure the rotor is secured and the chamber door
latched.10.
Set the
HOLD
mode set point to
5°C
above indicated
temperature.11.
Set the
RUN
mode set point to
5°C
below Indicated
temperature.12.
Place the
system
in the
RUN
mode.13.
The
meter indication should
be
less than 1.0
V
dc.14.
Move the
RUN
set point
towards the black
temperature
indicator pointer until
thepointer
is
completely
aligned
with
the black
temperature
Indicator pointer.
Thevoltage
should switch
to greater
than
+4.5
Vdc.15.
If the
voltage change occurs above or below the set
point,
align
the
set point
with
theblack
indicator,
then
adjust potentiometer
R43
accordingly.m.
Overtemperature Detection Set-Pointer
(R58)This
procedure adjusts
the
overtemperature set
point
to inhibit, or
disable the
operationof,
the
RUN
mode.1.
Set the main circuit breaker to
ON.7-8