Kendro HERAcell 150, Operating Instructions Manual

Page: 114 / 251

Name/Name Datum/Date Benennung/Designation
Erstellt/Prepared
D.Dornseiff 01/15/98
Index Änderung Name/Name Datum/Date
Service Handbuch HERAcell 150
Service Manual HERAcell 150
C 202613 D.Dornseiff 06/26/03
Dokumentnr./Document No. Seite/Page
Datei/File
50051109_04_EN_C.doc 50051109 / C 8/ 9
Weitergabe sowie Vervielfältigung dieser Unterlage, Verwertung oder Mitteilung ihres Inhalts nicht gestattet, soweit nicht ausdrücklich zugestanden. Zuwiderhandlungen ver-
pflichten zu Schadensersatz. Alle Rechte für den Fall der Patenterteilung oder Gebrauchsmustereintragung vorbehalten. © Kendro Laboratory Products GmbH, Germany
Sensor-specific data storage, NVRAM.
All sensor-block-specific data are stored in the NVRAM on the sensor
board. The master processor reads/writes this information via the PC bus.
Main board P003 (also main board or main PCB)
Provides the following functions:
Mains power connection:
Device power socket with integrated fuse holder
Power supply creation:
The combinational circuit component (input voltage range ~ 80 - 270 V)
generates the 12 V DC low power voltage for the electronic components.
Voltage is displayed by an LED. Power for the auto-zero air pump is derived
from the main PCB’s power supply.
Signal processing, water level sensor
Temperature and CO
2
calculation and regulation, O
2
regulation:
The measured values from the sensor board are adjusted by the offset and am-
plification, and corresponding set values are generated. Control of all software
routines. The O
2
concentration is calculated by a separate O
2
board, described in
more detail below. O
2
regulation is also a function of the main board.
Actuator controls:
All heating system actuators are located on the main PCB.
CO
2
solenoid activation:
The 12 VDC CO
2
solenoid is connected directly to the board.
Sample protection:
In case of overtemperature, a special software routine linked to a universally
switching relay assumes the temperature regulating function. This upper tem-
perature limit band (set value +1

C) acts as the trigger band for this controller.
The software attempts to readjust the unit to the specified desired temperature
value.
Temperature limiting during the decontamination routine:
If the upper temperature limit band (set value + 5

C) is exceeded during the
decontamination routine, a universal relay shuts the unit's heating system
down permanently.