Binder KBF 720 (E5.2) - Temperature Safety Device Class 3.3 (DIN 12880) (Option)

KBF / KBF P (E5.2) 02/2012 page 61/103
10.3 Temperature safety device class 3.3 (DIN 12880) (option)
With the option over/under temperature protective device (temperature safety device class 3.3 acc. to DIN
12880) the unit is equipped with two additional safety devices (class 3.1 and class 3.2). The combination
of the safety devices is regarded as a safety device class 3.3.
The temperature safety device, class 3.3, serves to protect the climatic chamber, its environment and the
contents from exceeding the maximum permissible temperature. Please observe the guideline BGI/GUV-I
850-0 on safe working in laboratories (formerly BGR/GUV-R 120 or ZH 1/119 laboratory guidelines issued
by the employers’ liability insurance association) (for Germany).
With safety device class 3.1 a maximum value for the temperature is set that the unit will not exceed due
to the regulatory function of the safety device class 3.1. This protection against excessively high tempera-
tures can, for example, serve to protect the climatic chamber, its environment and the material under
treatment from excess temperatures.
With safety device class 3.2 a minimum value for the temperature is set that the unit will not fall below
due to the regulatory function of the safety device class 3.2. This protection against excessively low tem-
peratures can, for example, serve to protect sensitive loads from under cooling.
Both safety devices are functionally and electrically independent of the temperature control system. If an
error occurs, they perform a regulatory function.
Safety devices class 3.1 (14) and class 3.2 (15) are located in the left lateral control panel.
With option temperature safety device class 3.3, the safety controller (chap. 10.2) must be set
to limit 100 °C / 212 °F.
(15)
(14)
Excess
temperature
Set-point
Insufficient
temperature
W
X
CONFI G
HAND
VIEW->
EXIT
W
08:43:55 20.09.02
TEMP
°C
40.0
36.8
HUMID
%rH
65.0
58.6
(1)
Figure 18: Temperature safety device class 3.3
10.3.1 Temperature safety device class 3.1
If you turn the control knob (14) to its end-stop (position 10), the safety de-
vice class 3.1 protects the appliance. If you set the temperature a little above
the set-point, it protects the charging material.
If the safety device class 3.1 has taken over control, identifiable by the red
alarm lamp (14a) lighting up, the message “TEMP ALARM” on the controller
will be displayed and the buzzer will sound, then proceed as follows:
• Reset the buzzer by pressing the “RESET” key on the controller
• Disconnect the unit from the power supply
• Have an expert examine and rectify the cause of the fault.
• Start the unit again as described in chap. 5.
(14a)
(14)