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3-2-2 Acceleration and Deceleration Modes
In order to meet a wide variety of applications, the acceleration and deceleration rates can be adjusted
between 0 to 500 rpm. By setting an ideal acceleration and deceleration time samples will not be
disturbed, which improves efficiency and reduces centrifugation time.
The table below shows the relationship between ACCEL and DECEL code numbers and acceleration
and deceleration time.
Speed
(rpm)
*1 Minimum time: The time it takes the drive motor to accelerate and decelerate the rotor using
*2 DECEL code "F": A deceleration method that does not involve brake control using the drive motor.
[Examples showing use of acceleration and deceleration modes)
Density gradient
centrifugation using a
vertical rotor
Using CsCl
density-gradient
sedimentation equilibrium
centrifugation for DNA
separation (when using a
uniform liquid)
Pelleting using an angle
rotor
Density gradient
centrifugation using swing
bucket rotor
With a swinging bucket rotor, there is little difference with regard to turbulence if
NOTE
ACCEL/DECEL is less than or equal to 8. However, rotor swinging may become large in
modes with long acceleration times, which could cause an imbalance alert to light even
within tolerable imbalance values.
Indicates ACCEL and
DECEL code numbers
(Free coast)
Time
maximum torque.
This time will vary with rotor type and the mechanical resistance of the drive motor.
The deceleration time will then vary widely depending on differences in the small
mechanical resistance of the drive motor and the vacuum level of the rotor chamber
and other factors.
Optimum
numeric code
ACCEL
5
9
9
8
Code
No.
9
8
7
6
5
4
3
2
1
0
*
(
2)
F
DECEL
As the density gradient reorients during
acceleration and deceleration, the gradient may be
7
disturbed if samples are rapidly accelerated and
decelerated.
You can operate at maximum acceleration because
the density gradient is not formed during the run.
Slow deceleration is recommended to obtain sharp
7
bands.
Rapid unloading of samples is possible.
9
(short separation time)
The sample and gradient do not reorient. For that
reason, there is less gradient turbulence than with a
vertical rotor and good results can be obtained as
8
long as rapid acceleration or deceleration are
avoided.
3-10
3-2-2 Acceleration and Deceleration Modes
Acceleration
(minutes) from 0
to 500 rpm
(*1)
time
Minimum
1
2
3
4
5
6
7
8
9
－
Separation characteristics
Deceleration from
(minutes) from
500 to 0 rpm
(*1)
time
Minimum
1
2
3
4
5
6
7
8
9
Free coast from
stable speed
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