BEKA BA307E-SS, Руководство пользователя

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The Ex e panel enclosure should be fitted with a
warning label saying 'Do not open when non-
intrinsically safe circuits are energised', alternatively
all bare live non-intrinsically safe parts within the
panel enclosure should have an IP30 cover carrying a
warning label 'Do not open when energised'.
The power dissipation within an indicator fitted with
operational alarms and a backlight which is separately
powered is normally about 350mW. In the very
unlikely event that all four circuits fail to the worst case
condition at the same time, the total power dissipation
rises to 3.4W which could raise the internal
temperature of a small thermally well insulated panel
enclosure.
4.3.2 Installation in Ex p panel enclosure within
Zone 1 or Zone 2.
Installation of a BA307E-SS or BA327E-SS indicator
in an Ex p IIC Gb or Ex p IIC Gc pressurised panel
enclosure does not invalidate the Ex p panel's impact
and ingress protection as the front of both indicators
comply with Ex p impact and ingress requirements.
Although mounted in an Ex p panel enclosure, the
BA307E-SS or BA327E-SS remain Group II Category
1G Ex ia IIC T5 Ga intrinsically safe apparatus and
must therefore be powered via a Zener barrier or
galvanic isolator as described in section 4.1 and 4.2 of
this manual to ensure that the instrument's front panel
push button switches are nonincendive.
When installed in an Ex p panel enclosure the four
vents at the rear of indicator which are shown in Fig 8
should not be obstructed.
Zener barriers and galvanic isolators may be installed
in the same Ex p enclosure as the indicator. All may
be mounted in an Ex px enclosure installed in Zones 1
or 2, or in an Ex pz enclosure installed in Zone 2, both
of which have a non-hazardous interior. Some Zener
barriers and galvanic isolators may have certification
permitting installation within an Ex py enclosure which
has a Zone 2 interior.
The indicator terminals, the wiring to the indicator and
the intrinsically safe interface, if mounted within the
enclosure, should be segregated from all other non-
intrinsically safe wiring and equipment within the panel
enclosure as required by EN 60079-11
Equipment
protected by intrinsic safety and EN 60079-14
Electrical installations design, selection and erection .
If live maintenance is anticipated, it is
recommended that the Ex p panel enclosure
should be fitted with a warning label saying 'Do not
open when non-intrinsically safe circuits are
energised', alternatively all bare live non-
intrinsically safe parts within the panel enclosure
should have an IP30 cover carrying a warning
label 'Do not open when energised'.
Fig 5 Typical installation in Ex p panel enclosure
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