Centrifugation Of Materials Or Mixtures Of Materials With A Density Higher Than 1.2 Kg/Dm; Rotor Recognition; Emergency Release - Hettich UNIVERSAL 320 Operating Instructions Manual

23

Centrifugation of materials or mixtures of materials with a density higher than 1.2 kg/dm

When centrifuging with maxim revolutions per minute the density of the materials or the material mixtures may not
3
exceed 1.2 kg/dm .
The speed must be reduced for materials or mixtures of materials with a higher density.
The permissible speed can be calculated using the following formula:
Reduced speed (n )
red
e.g.: maximum speed RPM 4000, density 1.6 kg/dm
1.2 kg/dm³
n = x 4000
red
1.6 kg/dm³
In the exceptional case that the maximum loading indicated on the hanger is exceeded, the speed must also be
reduced.
The permissible speed can be calculated using the following formula:
Reduced speed (n )
red
e.g.: maximum speed RPM 4000, maximum load 300 g, actual load 350 g
300 g
n = x 4000 RPM
red
350 g
If in doubt you should obtain clarification from the manufacturer.
24

Rotor recognition

Rotor recognition is carried out after each start of the centrifugation run.
If the rotor has been changed, the centrifugation run is canceled after rotor recognition. The rotor code (R xx) and the
maximum speed (n-max=xxxxx) of the rotor are displayed.
A further operation of the centrifuge is only possible after a single opening of the lid.
If the maximum speed of the rotor being used is less than the set speed, the speed is limited to the rotor's
maximum speed.
25

Emergency release

During a power failure the lid cannot be unlocked by motor. An emergency release has to be executed by hand.
For emergency release disconnect the centrifuge from the mains.
Open the lid only during rotor standstill.
See figure on page 2.

Switch off the mains switch (switch position "0").

Look through the window in the lid to be sure that the rotor has come to a standstill.

Insert the hexagonal wrench key into the bore hole (Fig. 1, A) and carefully rotate by half a turn in clockwise
direction until the lid can be opened.

Pull the hexagon socket head wrench out of the drilling again.

If the left LED in the
OPEN / STOP
button so that the motor-driven lid lock goes into the basic position (opened) again.
1.2
=
Greater density [kg/dm³]
3
RPM = 3464 RPM
maximum load [g]
= x maximum
actual load [g]
= 3703 RPM
button flashes after the centrifuge is switched on again, press the
x maximum speed [RPM]
speed [RPM]
EN
3
OPEN / STOP
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