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Instruction for use | Supercal 5
Only platinum temperature sensors with type approval in the Pt500 version are recommend-
ed. These must be paired and used in two-wire technology up to a cable length of 3 m. The
connecting cables must not be separated, extended, or shortened.
For lengths of more than 3 m, we recommend the use of carefully shielded cable lines of the
same length. The approval of the Supercal 5 allows 2-wire temperature sensors to be used
up to a maximum length of 15 m and 4-wire temperature sensors up to a maximum cable
length of 50 m. Su-percal 5 can be used with a maximum cable length of 50 m.
The temperature sensors should preferably be installed directly and without thermowell for
low-temperature heating systems due to the minimum temperature spread. This allows even
the smallest temperature differences to be determined without delays and heat dissipation
errors.
In pipelines up to DN 150, the temperature sensors are installed directly or employing ther-
mowell. The dynamic measuring range of the sensor tip is located as far as possible in the
middle of the pipeline.
Extensive information on the subject of temperature sensors can be found in our Sontex
temperature sensor overview at: www.sontex.ch/downloads/ under the heading tempera-
ture sensor 460.
4.7.1 Installation Instructions For Temperature Sensors
5
6
7
8
5/6
Temperature high
7/8
Temperature low
r
w
r
w
Since it is not the absolute temperature but the exact temperature difference that is im-
portant when measuring the heat quantity, both sensor cables must be the identical length
(resistance). The sen-sors are very accurately computer paired in the factory and may only
be used in the original pairing.
EN1434-2 2004 prescribes the following maximum cable lengths for 2-wire temperature
sensors:
Wire cross-section
Maximum cable length
Pt500
0,22 mm
2
12,5 m
0,50 mm
2
25,0 m
0,75 mm
2
37,5 m
1,50 mm
2
75,0 m
