11
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 BA364D is available ATEX certified
for use in the presence of combustible dusts. If
ATEX dust certification is required it must be
requested when the BA364D Counter, Timer,
Tacho, Clock is purchased.
WARNING
Before installing a BA364D in the
presence of a combustible dust, 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 BA364D has been ATEX certified as Group
II, Category 1 GD apparatus Tamb = -20 to 60
o
C,
with a Maximum Surface Temperature of 80
o
C.
When installed as specified by EN 50281 Part 1-
2 ‘Selection, installation and maintenance of
electrical apparatus protected by enclosures’, the
instrument 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 dusts having a Minimum Ignition
Temperature of:
Dust cloud
120
o
C
Dust layer on BA364D
155
o
C
up to 5mm thick
Dust layer on BA364D
Refer to
over 5mm thick.
EN500281
part 1-2
At an ambient temperature between -20 and
+60
o
C
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.
The instrument serial number and date of
manufacture are recorded on a separate label
inside the terminal compartment.
A1.3 Calibration & maintenance
The ATEX dust certification relies on the
instrument enclosure being dust-tight. 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 ensure that the sealing gaskets
are undamaged and are free from foreign bodies.