Automatic Temperature Monitor (Asf); Mechanical Temperature Monitoring: Temperature Limiter (Tb); Adjusting Temperature Monitoring - Memmert UN PLUS Series Operating Instructions Manual

5.5.3 Automatic temperature monitor ( ASF)
ASF is a monitoring device that automatically follows the set temperature setpoint within an
adjustable tolerance band (Fig. 19 ).
The ASF – if switched on – is automatically activated as soon as the actual temperature value
reaches 50 % of the set tolerance band of the setpoint (in the example: 180 °C – 1.5 K) for the
first time (section A).
When the temperature violates the set tolerance band around the setpoint (in the example in
Fig. 19:
180 °C ± 3 K) – e.g. if the door is opened during operation (section B of illustration) – the
alarm is set off. The ASF alarm is automatically triggered as soon as 50 % of the set tolerance
band of the setpoint (in the example: 180 °C ± 1.5 K) are reached again (section C).
If the temperature setpoint is altered, the ASF is automatically disabled temporarily (in this
example: The setpoint is changed from 180 °C to 173 °C, section D) until the tolerance range
of the new temperature setpoint is reached again (section E).
183 °C
180 °C
177 °C
ASF active
Fig. 19 Schematic diagram of how the ASF temperature monitoring works
5.5.4 Mechanical temperature monitoring: Temperature limiter ( TB)
The appliance is equipped with a mechanical temperature limiter (TB) of protection class 1 in
accordance with DIN 12 880.
If the electronic monitoring unit should fail during operation and the factory-set maximum
temperature is exceeded by approx. 20 °C, the temperature limiter, as the final protective
measure, switches off the heating permanently.

5.5.5 Adjusting temperature monitoring

1. Press the activation key to the left of the
ALARM
display. The
temperature protection) is automatically
activated.
A B
183 °C
177 °C
AUTO
ASF alarm
min
setting (under-
C D
AUTO
ASF active
Operation and control
E
176 °C
170 °C
t
AUTO
ASF active
ALARM
ALARM
min
60
0 . °C
min
auto
000°C
max
max
120
000°C
.0 °C
auto off
+ / - 0.0
+
K
- 99K
31