Hettich 4701 - ‎7.4.2 Standby cooling‎; ‎7.4.3 Precooling the rotor‎; ‎7.4.4 Delayed cooling‎

AB4701en_SARev.: 05 / 11.2023
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Software operation
For centrifuges with the heating/cooling option, the temperature setpoint
can be adjusted from -20°C to +90°C or from -4°F to +194°F .
The lowest achievable temperature is rotor dependent.
7.4.2
Standby cooling
When the rotor is at a standstill and the lid is closed, the centrifuging
chamber is cooled to the preselected temperature if this is less than 20°C
or 68°F.
The preselected temperature is displayed during standby cooling.
7.4.3
Precooling the rotor
For rapid pre-cooling of the unloaded rotor and accessories, we recom-
mend a centrifugation run with the continuous run settings and a speed of
■ Swing-out rotor: approx. 20%of the maximum rotor speed used.
■
Angle rotor: approx. 40%of the maximum rotor speed used.
The centrifugation run, for precooling of the rotor, takes place automatically
with the PREC program (PRECOOLING).
A centrifugation run, for precooling the rotor, cannot be executed when
working with program links.
The rotor is stationary.
1. Press the [Cooling] button.
🡆 The button ashes until the rotor is read in for precooling.
The button lights up once the rotor has been read in.
The rotor speed or the resulting RCF value, the temperature in
the centrifuging chamber (only for centrifuges with cooling) and the
remaining or elapsed time are displayed during the centrifugation
run.
2. Press the [STOP/OPEN] button.
🡆 Precooling of the rotor is terminated.
Ramp-down takes place with the selected brake level.
The brake level is displayed.
7.4.4
Delayed cooling
If required, the settings can be adjusted so that cooling takes place with
a time delay after the centrifugation run has started. The delay time is
adjustable from 15 to 900 seconds, in 1 second increments. No delay time
is set ex works.
1. Press and hold the [PROG] button.
🡆 ‘***Machine Menu***’ is displayed after 8 seconds.
2. Press the [PROG] button repeatedly until ‘-> Settings’ is displayed.
3. Press the [START] button.
🡆 ‘SOUND / BELL = on’ or ‘SOUND / BELL = off’ is displayed.
4. Press the [PROG] button repeatedly until ‘Cool acc time = 0’ is dis-
played.
5. Use the [Rotary knob] to set the desired value.
0 = no delay time