46
ABB i-bus
®
EIB / KNX
Planning and application
Fig. 33: Measurement curve for the PT100
The two hatched lines indicate the possible further progression of the
measurement curve. The manufacturer guarantees the standardised values
for the measuring range from – 20 °C to + 60 °C. This example shows that
the resistance values of < – 20 °C and > + 60 °C do not correspond to the
standard resistance values.
Measurement curve taking all specifications into account:
Fig. 34: Measurement curve for the PT100 with threshold values
Measurement curve of the PT100
85
90
95
100
105
110
115
120
125
130
-30
-20
-10
0
10
20
30
40
50
60
70
Measuring range in °C
Output
signal
in
Ohm
85,00
90,00
95,00
100,00
105,00
110,00
115,00
120,00
125,00
130,00
-30,00
-20,00
-10,00
0,00
10,00
20,00
30,00
40,00
50,00
60,00
70,00
Measuring range in C
Output
signal
in
Ohm
Threshold 1: upper limit
Threshold 1: lower limit
Threshold 2: upper limit
Threshold 2: lower limit
Measurement curve with threshold values
