Memmert Universal ovens U plus, Incubators I plus, Sterilisers S plus User Manual
Page 32
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D24026 | Date 10/2014
Operation and control
5.5.1 Electronic temperature monitoring (TWW)
The manually set monitoring temperature
min
and
max
of the electronic overtemperature
max
max
control is monitored by an adjustable over/undertemperature controller (TWW) protection
class 3.1 acc. to DIN 12 880 (or over/undertemperature controller (TWW) protection class 3.1
for UIS appliances). If the manually set monitoring temperature
max
is exceeded, the TWW
max
max
takes over temperature control and begins to regulate the monitoring temperature (Abb. 18).
t
°C
Setting MAX
Set temperature
Controller error
Emergency operation
Abb. 18 Schematic diagram of how the TWW temperature monitoring works
5.5.2 Electronic temperature limiter (TWB) protection class 2 acc. to DIN 12 880
If the manually set monitoring temperature
max
is exceeded, the TWB switches off heating
permanently (Abb. 19 ) and can be reset by pressing the confirmation key.
In programme mode, the current programme is resumed for TWB alarms of up to 15
minutes. If the alarm is active for more than 15 minutes, the programme is cancelled.
t
°C
heating switched off by TWB
Setting Max
Set temperature
Controller error
Abb. 19 Schematic diagram of how the TWB temperature monitoring works