Binder 9020-0402, Translation Of The Original Operating Manual

Page: 81 / 173

MK LIT (E5) 01/2021 page 81/172
If the actual temperature exceeds the nominal temperature by approx. 20 °C, the over temperature protec-
tive device permanently turns off the chamber. The user cannot restart the chamber again. The protective
cut-off device is located internally. Only a service specialist can replace it. Therefore, please contact an
authorized service provider or BINDER Service.
15.2 Temperature limiter class 2
A temperature limiter class 2 acc. to DIN 12880:2007 provides additional safety in the event of a fault. This
is fixed at 120 °C .
When this temperature is reached, the heating, cooling and fan of the test cabinet are switched off and the
appliance controller remains on.
Resetting via a reset button not accessible to the user is always carried out by BINDER Service.
The adjustable safety controller class 2 and optional safety devices class 2 remain functional and offer
additional protection against excessive temperatures for the chamber.
15.3 Overtemperature safety controller (adjustable temperature limiter class 2
The chambers are regularly equipped with an electronic overtemperature safety controller (temperature
safety device class 2 according to DIN 12880:2007). The safety controller is functionally and electrically
independent of the temperature control system and serves to protect the chamber, its environment and the
contents from exceeding the maximum permissible temperature.
With option temperature safety device class 3.3 (chap. 15.4), the safety controller is not
used. In this case it must be set to the maximum temperature.
Please observe the regulations applicable to your country (for Germany: DGUV guidelines 213-850 on safe
working in laboratories, issued by the employers’ liability insurance association).
When the entered safety controller set-point is reached, the overtemperature safety controller turns off the
heating, fan, and refrigeration system. This condition (state of alarm) is indicated visually and additionally
with an audible alert if the buzzer is enabled (chap. 13.2.5). The alarm persists until the chamber cools
down below the configured safety controller setpoint and the alarm is manually reset.
Check the setting regularly and adjust it following changes of the set-point or charge.
The safety controller only activates after the set-point has been reached once.
15.3.1 Safety controller modes
You can select between “Limit (absolute)” and “Offset (relative)” safety controller mode
• Limit: Absolute maximum permitted temperature value
This setting offers high safety as a defined temperature limit will not be exceeded. It is important to adapt
the safety controller set-point after each modification of the temperature set-point. Otherwise, the limit
could be too high to ensure efficient protection, or, in the opposite case, it could prevent the controller
from reaching an entered set-point outside the limit range.
•
Offset: Maximum overtemperature above any active temperature set point. The maximum temperature
changes internally and automatically with every set-point change.
This setting is recommended for program operation. It is important to check the safety controller set-
point and safety controller mode occasionally, as it does not offer a fix, independent limit temperature
value, which would never be exceeded.