Hach BioTector B3500C User Manual

Page 133
8.3.11 Cooler Program
MODE T CONTROL
 MODE defines the operation mode of the Cooler. Cooler
operates automatically with the default TEMPERATURE
CONTROL setting, to achieve the programmed TEMPERATURE
DIFFERENCE below.
 When MODE is programmed as PWM “PULSE WIDTH
MODULATION”, the Cooler operates using the BACKUP PWM
DUTY setting below.
BACKUP PWM DUTY 10%
 BACKUP PULSE WIDTH MODULATION DUTY defines the
operation of the cooler in back-up mode, i.e. when there is a
fault with the Cooler or with the BioTector temperature sensor
(i.e. when system generates 107_COOLER FAULT and/or
108_COOLER FAN FAULT or 113_TEMP SENSOR FAULT
warning events). The default 10% setting means that the Cooler
is activated for 10% of the time and deactivated for 90% of the
time.
 The BACKUP PWM DUTY mode is automatically cancelled
when the relevant faults are acknowledged in the Fault Archive
menu.
50% PWM OFFSET 14.0C
 The 50% PWM OFFSET setting (14°C by default) is the
midpoint offset of the cooler temperature calibration curve, which
is linear. When Cooler operates with PULSE WIDTH
MODULATION at 50%, the Cooler temperature is typically
~14°C below ambient temperature, which is ~25°.
50% PWM SLOPE 5.00%/C
 The 50% PWM slope setting (5% per 1°C by default) is the
slope of the cooler temperature calibration curve at midpoint.
When Cooler operates with PULSE WIDTH MODULATION at
50%, the Cooler temperature changes by ~1°C with every 5%
change in PULSE WIDTH MODULATION.
T DIFFERENCE 16.0C
 TEMPERATURE DIFFERENCE (16% by default) defines the
temperature difference to be achieved between the BioTector
temperature and the Cooler temperature. BioTector temperature
sensor is located on the O2-Controller Board. Cooler
temperature is achieved with the settings described above.
 Cooler Temperature = BioTector Temperature –
TEMPERATURE DIFFERENCE.
 When BioTector detects that the Cooler temperature will drop
below 5°C applying above settings, system automatically
decreases the PULSE WIDTH MODULATION so that the
temperature of the Cooler does not drop below 5°C. This is
carried out to avoid possible freezing of the condensate water,
which could be present inside the Cooler.

Hach BioTector B3500C Specifications

General

Brand	Hach
Model	BioTector B3500C
Category	Measuring Instruments
Language	English