Appendix 1
ATEX Dust Certification
A1.0 ATEX dust certification
In addition to ATEX certification permitting
installation in explosive gas atmospheres which is
described in the main section of this instruction
manual, the BA354E Rate Totaliser is available
wiith ATEX dust certification. Dust certification is
an option which must be specified when the Rate
Totaliser is ordered.
CAUTION
Before installing a BA354E Rate Totaliser
in the presence of a combustible dust
atmosphere, ensure that the certification
information label which is located on the
top of the instrument specifies dust
certification - see section A1.2
A1.1
Zones, and Maximum Surface
Temperature
The BA354E has been ATEX certified as Group II,
Category 1D Ex ia IIIC T80ºC Da IP66 Ta = -40 to
70°C. When installed as specified by EN 60079-14
the the Rate Totaliser may be installed in:
Zone 20
explosive atmosphere in the form of
a cloud of combustible dust in air is
continuously present, or for long
periods or frequently.
Zone 21
explosive atmosphere in the form of
a cloud of combustible dust in air is
likely to occur occasionally in normal
operation.
Zone 22
explosive atmosphere in the form of
a cloud of combustible dust in air is
not likely to occur in normal
operation, but if it does occur, will
only persist for a short period.
Be used with dust in subdivisions:
IIIA
combustible flyings
IIIB
non-conductive dust
IIIC
conductive dust
Having a Minimum Ignition Temperature of:
Dust cloud
120°C
Dust layer on the Rate
Totaliser
155
°
C
up to 5mm thick
Dust layer on the Rate
Totaliser over 5mm thick
Refer to
EN 61241-14
At an ambient temperature between -40 and +70°C
Note:
The specified operating temperature of the
BA354E is –20 to +70ºC. At temperatures below
–20ºC the instrument will continue to totalise but
the display will not function.
A1.2 Certification Label Information
The certification label is fitted in a recess on the
top outer surface of the enclosure. It shows the
ATEX dust certification information including the
maximum surface temperature and ingress
protection, plus the ATEX gas certification
information. Non European information may also
be shown.
BA354E label including dust certification
The instrument serial number and date of
manufacture are recorded on a separate label
inside the terminal compartment.
A1.3 Installation and maintenance
The the Rate Totaliser’s ATEX intrinsic safety dust
certification relies on the ingress protection
provided by the instrument enclosure to prevent
dust accumulating on the field terminals and
internal switches. Therefore the control and
terminal covers should only be removed when dust
can not enter the instrument enclosure. Before
replacing the control and terminal covers the
sealing gaskets should be inspected to ensure that
they are undamaged and are free from foreign
bodies.
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