FED (E2) 12/2014
page 30/55
7.
Temperature safety devices
7.1 Temperature safety device class 2 (DIN 12880)
The temperature safety device class 2 protects the chamber, its environment and the charging material
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).
In the event of a fault in the temperature controller, the safety device (7)
permanently
turns off the
chamber. This status is reported visually by the indicator lamp (7a) and, in case of the option audible
alarm with activated buzzer (chap. 7.3), by the buzzer sounding.
Check the operation of the safety device (7) by moving it slowly counter-clockwise until the chamber turns
off. The safety device cut-off is reported visually by the indicator lamp (7a) and, in case of the option
audible alarm with activated buzzer (chap. 7.3), by the buzzer sounding.
Then release again the safety device by pressing the reset button (7b) and turn on the chamber as
described.
Figure 7: Temperature safety device class 2
Function:
The safety device class 2 is functionally and electrically independent of the temperature control device
and turns off the chamber permanently.
If you turn the control knob (7) to its end-stop (position 10), the safety device protects the appliance. If
you set it to a temperature a little above the controller’s set-point temperature, it protects the charging
material.
If the safety device has turned off the chamber, identifiable by the red alarm lamp (7a) lighting up and, in
case of the option audible alarm with activated buzzer (chap. 7.3), by the buzzer sounding, proceed as
follows:
•
Disconnect the chamber from the power supply.
•
Have an expert examine and rectify the cause of the fault.
•
Release the safety device by pressing the reset button (7b).
•
Restart the chamber as described in chap. 5.
Setting:
To check the response temperature of the safety device, turn on the chamber and set the desired set-
point at the temperature controller.
The scale division from 1 to 10 corresponds to the temperature range from 30 °C /
86 °F
up to 320 °C /
608 °F
and serves as a setting aid.
(7)
(7a)
(7b)
