Sontex Supercal 5 I, Instructions For Use Manual

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19 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 adequately shielded cable runs of
equal 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. Supercal 5 can be used with a maximum cable length of 50 m.
The temperature sensors should preferably be installed directly and without pockets 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, temperature sensors may be installed directly or using pockets.
The sensor tip should be located as close as possible to 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 of 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 of identical length
(resistance). The sensors are very accurately computer paired in the factory and may only be
used in the original pairs.
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