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APPENDIX 1
Use in an Ex e or Ex p panel enclosure located
in Zone 2.
The ATEX and IECEx certificates for the BA307NE
and BA327NE indicators permit the instruments to
be installed in an Ex e increased safety panel
enclosure located in Zone 2, or in an Ex p
pressurised panel enclosure located in a Zone 2
hazardous area.
A1.1 Installation in Ex e panel enclosure within
Zone 2
Installation of a BA307NE or BA327NE indicator in
an Ex e increased safety panel enclosure does not
invalidate the Ex e panel's ingress and impact
protection as the front of both indicators comply
with Ex e ingress and impact requirements.
Although mounted in an Ex e panel enclosure, the
BA307NE or BA327NE remain protected by
Group II Category 3G Ex nA ic IIC T5 Gc
certification described in the main section of this
manual and the front panel push button contacts
remain intrinsically safe Ex ic.
In normal operation i.e. without faults, the
maximum power dissipation within the indicator is
less than 150mW which is very unlikely to modify
the internal temperature of the Ex e panel
enclosure.
CAUTION
BA307NE and BA327NE indicators should
not be installed in an Ex e panel enclosure
located in Zone 1.
There are four design requirements:
1. The indicator should be installed generally as
shown in section 5 and Fig 20.
2.
The certificate specifies that the indicator
should be connected to a
limited energy
4/20mA circuit having a maximum output
current of 200mA. A
low voltage supply,
usually 24V, that is safe in normal operation
and suitable for live connection i.e. CE
marked, is usually considered acceptable.
3. Wiring should comply with Clause 9 of
BS EN 60079-14.
4. The 4/20mA input must be able to supply the
1.2V required to operate the indicator. This
increases to 5.0V if the indicator includes an
optional loop powered backlight. See 9.5.1.
Fig 20 Typical installation in Ex e panel enclosure
A1.2 Zone 2 installation in Ex p enclosure
Installation of a BA307NE or BA327NE indicator in
an Ex p pressurised panel enclosure does not
invalidate the pressurised panel's ingress and
impact protection as the front of the indicator
complies with Ex
p ingress and impact
requirements. Although mounted in an Ex p panel,
enclosure the BA307NE or BA327NE remain
protected by Group II Category 3G Ex nA ic IIC T5
Gc certification described in the main section of
this manual and the front panel push button
contacts remain intrinsically safe Ex ic.
CAUTION
BA307NE and BA327NE indicators should
not be installed in an Ex p panel enclosure
located in Zone 1.
Fig 21 Typical installation in Ex p panel enclosure
