2-4
Description
DRIVE
The drive spindle is directly driven by a brushless, high-torque,
switched-reluctance drive motor. The instrument’s resilient suspen-
sion minimizes disturbance of the sample during acceleration and
deceleration, and reduces damage to the drive spindle if an imbalance
occurs during centrifugation.
FRICTION REDUCTION SYSTEM (FRS)
The friction reduction system (FRS) uses a mechanical rotary vane
vacuum pump to reduce chamber pressure to approximately one-
quarter atmosphere (190 mm Hg). The pump turns on after the run is
started, before rotor friction reaches a high level. When the required
vacuum level is reached, the pump turns off. Vacuum in the chamber
is vented during rotor deceleration.
TEMPERATURE SENSING AND CONTROL
The temperature control system, cooled by circulation of a non-CFC-
based refrigerant, is activated when the centrifuge power is on and
when the door is closed.
A thermistor in the rotor chamber continuously monitors the chamber
temperature. The system calculates the chamber temperature required
to maintain the set rotor temperature, ±2°C.
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Although the chamber
temperature fluctuates during operation, the rotor’s large mass keeps
the sample temperature substantially constant. At the end of a run, the
system continues controlling the temperature to prevent freezing or
overheating of the sample.
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Refer to the applicable rotor manual for specific temperature information.
