Vega FIBERTRAC 31, Быстрая настройка

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2 Product description
FIBERTRAC 31 • Four-wire 4 … 20 mA/HART
62067-EN-211203
The level is detected contactlessly right through the vessel wall.
Neither a process fitting nor a vessel opening are required. The instru-
ment is thus ideal for retro installation.
In radiometric measurement, a Caesium-137 or Cobalt-60 isotope
emits focussed gamma rays that are attenuated when penetrating
the vessel wall and the medium. The PVT detector on the opposite
side of the tank receives the radiation, whose strength is dependent
on the level. The measuring principle has proven to be very reliable
in conjunction with extreme process conditions because it measures
contactlessly from outside through the vessel wall. The measuring
system ensures maximum safety, reliability and plant availability,
independently of the medium and its properties.
2.3 Corresponding source container
A radioactive isotope in a suitable source holder is the prerequisite for
a radiometric measurement setup.
The handling of radioactive substances is regulated by law. The radia-
tion protection rules of the country in which the system is operated
apply first and foremost.
In Germany, for example, the current radiation protection ordinance
(StrlSchV) based on the Atomic Energy Law (AtG) applies.
The following points are important for measurement with radiometric
methods:
A handling permit is required for operation of a system using gamma
rays. This permit is issued by the respective government office or the
responsible authority (in Germany, for example, offices for environ-
mental protection, trade supervisory boards, etc.)
You can find further instructions in the operating instructions manual
of the source container.
When handling radioactive sources, unnecessary radiation exposure
must be avoided. An unavoidable radiation exposure must be kept as
low as possible. Take note of the following three important measures:
1 2 3
Fig. 2: Measures for protection against radioactive radiation
1 Shielding
2 Time
3 Distance
Functional principle
Handling permit
General instructions for
radiation protection