Operating Mode Autoaccurate - Heidolph Hei-VAP Industrial Betriebsanleitung

Operation

Operating mode AUTOaccurate

In this operating mode, the vacuum pressure is regulated automatically and depending
on the temperature.
The rotation speed and heating bath temperature are manually set by the operator as
in the SETpressure mode.
AUTOaccurate function
The temperature-dependent vacuum control feature AUTOaccurate is based on two
values:
– Inlet temperature cooling liquid: This value is measured with a temperature
sensor (PT 100) at the chiller inlet on the rear of the device (see section
"Mechanical design" on page 92)
– AUTOaccurate temperature: This temperature is measured at the
AUTOaccurate sensor in the condenser
In order to use the function, a value �T must be defined in the device control (param-
Auto Accurate
eter
temperature of the cooling liquid.
The sum �T + inlet temperature cooling liquid serves as a reference value for
the shutdown of the vacuum pump, i.e. if this temperature value is measured at the
AUTOaccurate sensor in the condenser after the process has started, the evacuation
stops.
As soon as the temperature at the AUTOaccurate sensor has subsequently decreased
by a defined value again, the vacuum pump is switched on and the system will be
evacuated again until the reference value at the sensor is reached again (with relatively
increased vacuum pressure) and the vacuum pump switches off again.
In this way, a consistent performance is achieved in the processing of solvents or
mixtures throughout the distillation process.
The described process steps are repeated until a defined maximum vacuum pressure is
reached (input value
process is then switched off.
PRACTICAL TIP
Before starting the process in AUTOaccurate mode, ensure that all
set process temperatures are reached in a stable manner (observe
display values!). Only then can the best possible and constant
distillation results be achieved!
A warm-up time of 15 minutes is recommended as a guide. Use the
device's warm-up function (
start page).
To open the start window of this mode, touch the
window:
, see the following figure). This value is added to the inlet
Vacuum & Vapor Temperature end p
→
Warm Up
button in the footer of the
Auto Accurate
129
). The distillation
button on the start