Connection In Hazardous Zones With Explosive Atmospheres - Siemens SITRANS TH400 Operating Instructions Manual

5.3

Connection in hazardous zones with explosive atmospheres

When installing the device in hazardous areas, use housings with the degree of protection
corresponding to the inspection certificate valid in your country. Observe the specifications
of the EC-type examination certificate or the inspection certificate valid in your country.
The bus input circuit and sensor circuit are galvanically isolated and tested with a test
voltage of AC 500 V/1 minute. According to the intrinsic safety rules of explosion protection,
the requirements for separating the bus input circuit from the ground are met.
The galvanical isolation does not meet the requirements for an "infallible galvanical isolation"
in the sense of the intrinsic safety standards EN 50020 or IEC 60079-11. Be sure to observe
the construction directives valid at the construction location for electrical resources in
hazardous areas. In Europe, this is the standard EN 60079-14.
Use only cable entries and covers that are approved for the relevant use.
At an ambient temperature ≥ 60°C, use heat-resistant cables approved at least for an
ambient temperature at least 20 K higher.
Zone 0 and Zone 1
● Only connect the transmitter to devices that are certified as intrinsically safe in
● If the connection head is made of aluminum, the requirements of EN 50284, section 4.3.1
Zone 2 in type of protection "nL" - limited energy
● Install the SITRANS TH400 transmitter in a housing meeting the protection IP54 per EN
● Only connect the transmitter to the following devices:
● The maximum approved input voltage is U
SITRANS TH400
Operating Instructions, 02/2007, A5E01018688-01
Warning
accordance with the EC-type examination certificate. Be sure to comply with the
parameters and limits listed there.
must be observed for uses where the device category 1 G is required.
60529, e.g. in a type B connection head per DIN 43729.
– Devices that are certified as intrinsically safe in category 1 or 2.
– "nL" certified devices (limited energy) in category 3.
values for external capacitance and inductance. You can find the permissible values in
the chapter "Technical data".
5.3 Connection in hazardous zones with explosive atmospheres
= DC 30 V. Observe the relevant permitted
i
Connecting
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