Heidolph LABOROTA 20 compact and safety - Manual (Page 86)

86
E
Extended actuation of the Start Stop key discontinues evacuation, the aerating valve opens, the
vacuum valve is closed.
Vacuum LED illuminates, when “vacuum control” was selected with the Start Stop key.
Ventilation LED illuminates, when the aerating valve is open.
Valve LED illuminates, when the vacuum valve is open.
Valve LED flashes, when evacuation was interrupted without aeration.
15. T auto vacuum control mode
In this mode, vacuum pressure level is controlled by an optional temperature sensor. For
installation refer to Options Section (page 93).
T auto is a low-pollution mode. This special vacuum control allows very low quantities of solvents
to be extracted by the vacuum pump.
The T auto temperature sensor detects temperature in the middle of the condenser.
For cooling water temperature, the LABOROTA 20 control uses a separate temperature sensor
(act Chiller).
Set

T auto is set to 2 – 10 °C (temperature difference from cooling water).
A high Set

T auto value results in high-speed distillation, whereas a low value renders a slow and
controlled distillation process.
When reaching the temperature difference (in the condenser) once set with Set

T auto, the
vacuum valve closes; as soon as the temperature drop equals Set

Vapor (hysteresis), the valve
will open once more. A current

Vapor setting is 0.5°C.
Pressing the Select key changes display
reading between Act Vapor, Act T auto,
Set

T auto and Set

Vapor.
The Act Vapor, Act T auto, Set

T auto or
Set

Vapor will illuminate.
Act T auto shows command temperature in
the condenser for mode T auto, i.e. at point
5 (see page 108), as soon as the
temperature sensor is installed and
connected with #4 plug connector (T auto
temperature sensor) (see page 108).
Act Vapor shows vapor temperature in the
Display
Act T auto LED
Act Vapor LED

T auto LED

Vapor LED
Select key
increase
decrease