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Manual BVS 21 ATEX E 069 X
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The controls are fitted with Phoenix Contact type
UT terminal blocks in the factory.
The tightening torques shown in the tables in
Annex A (page 24) must be complied with.
If other terminals are installed, the appropriate
torques and cable cross sections must be ascer-
tained from the supplier's installation instruc-
tions.
The terminals used for circuits with increased
safety 'e' protection must be arranged so that the
creepage distances and clearances called for by
IEC 60079-7 Table 1 for the operating voltage
concerned are met.
The terminals used for intrinsically safe circuits
do not require certification, but they must always
be specially marked, e.g. with a light blue color.
The terminals must be arranged so that at least
50 mm clearance (line of sight) exists between
bare parts of the terminals or connected conduc-
tors of the intrinsically safe and non-intrinsically
safe circuits. This clearance is achieved with
separating plates or by using suitable end
clamps for installation. The clearance between
the terminals of the intrinsically safe circuits and
earthed metallic parts must be at least 3 mm,
unless the terminals are themselves used for
earthing. Finally, suitable terminals or separating
plates must be used to ensure a clearance of at
least 6 mm between the terminals of different
intrinsically safe circuits.
In the case of mixed circuitry involving some Ex
i intrinsically safe circuits, the terminals for the
non-intrinsically-safe circuits must be covered
with guards of insulating material complying with
IP 30 to prevent accidental contact. Only guards
supplied for this purpose by the manufacturer
may be used. The guard must be provided with
a permanent, durable warning sign.
In order to ensure an orderly arrangement of the
conductors and secure connection of the con-
ductors to the installed terminal blocks and com-
ponents, a minimum clearance between the
enclosure interior wall and these components or
Edition October 2021
thuba Ltd., CH-4002 Basel
Copyright
Switzerland
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