Thermo Scientific SORVALL RC-5C PLUS, User Manual

Page: 19 / 55

Controls, Displays, and Indicators SORVALL ® Centrifuges
3-4
OFF/BRAKE Switch
When the OFF/BRAKE switch is set to BRAKE, the rotor will brake
(rather than coast) all the way from set speed to 0 rpm at the end of
the run, unless the OFF/ARC switch is set to ARC; if this is the case,
the rotor will brake from set speed to 768 rpm, then continue to
decelerate to 0 rpm at a controlled rate.
When the OFF/BRAKE switch is set to OFF the rotor will coast all
the way from set speed to 0 rpm at the end of the run, unless the
ARC is on; if this is the case it will coast to 768 rpm, then continue to
decelerate at the controlled rate.
START Switch
The START switch starts the run when is it pressed.
STOP Switch
The STOP switch ends the run when it is pressed.
RPM/RCF Switch
This switch is normally set to RPM, which causes the SPEED display
to show rotor speed. When pressed down to RCF during a run, the
SPEED display numbers will change from the current rotor speed to
the current relative centrifugal force (RCF, commonly referred to as
g force) value. To be sure that the RCF value is correct, make sure
the proper rotor code number is set on the ROTOR CODE switches.
When the RPM/RCF switch is released, the display will change
back to show rotor speed.
This switch can also be used to calculate RCF values before a run
has been started (see Chapter 4).
OFF/ARC Switch
When the OFF/ARC switch is set to ARC it causes an automatic
rate-controlled slow start from 0 rpm to 512 rpm and a slow stop
from 768 rpm to 0 rpm. The setting of the OFF/BRAKE switch will
determine the rate of deceleration from set speed down to
768 rpm—if it is set to OFF, the rotor will coast from set speed to
768 rpm; if it is set to BRAKE, the rotor will brake from set speed to
768 rpm.
If the OFF/ARC switch is set to OFF, the rotor will accelerate to set
speed at the normal (maximum) rate, then it will decelerate from set
speed down to 0 rpm in accordance with the setting of the OFF/
BRAKE switch.