5
UK
4.1.2 Sensor backup / redundancy switching
If one of the two temperature measuring channels fails (e�g� short circuit of one of
the two sensor elements) the temperature can still be measured with the channel
which is still operational (sensor backup). However, drift monitoring is not possible
any more�
The characteristics of the unit if one measuring element fails is defined by means
of the parameter drEd�
4.1.3 Response of the outputs in case of a fault
Fnr Type of fault
drEd = OFF
drEd = On
drEd = Ondr
DA
AA
DA
AA
DA
AA
0
No fault, no anomaly occurred�
N
T
N
T
N
T
10 Fault during power-on self test�
A
F
A
F
A
F
20 Internal malfunction in the sensor
electronics�
A
F
A
F
A
F
21
Partial malfunction in the sensor
electronics, measurement with one
channel still possible�
A
F
W
T/B
W
T/B
30 Short circuit in switching output Out1
(diagnostic output).
X
T
X
T
X
T
40 Malfunction on the analogue output�
A
X
A
X
A
X
41 Load for analogue output of too high
impedance�
A
X
A
X
A
X
42
Analogue signal at the lower limit value,
no linear transmission of the measured
value possible any more� Measured
temperature is below ASP value�
W
T
W
T
W
T
43
Analogue output at the upper limit value,
no linear transmission of the measured
value possible any more� Measured
temperature has exceeded AEP value�
W
T
W
T
W
T
51 Interruption measuring element 1
(NTC).
A
F
W
T/B
W
T/B
52 Short circuit measuring element 1
(NTC).
A
F
W
T/B
W
T/B
53
Temperature of the probe above
the operating temperature range
(170 °C).
A
F
A
F
A
F
54 Temperature of the probe below the
operating temperature range (-32 °C).
A
F
A
F
A
F
