BEKA BA364G, Руководство пользователя

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When set as required press
)
to enter the value
and return to the
20 . 000
prompt in the 4/20mA output
sub-menu.
Notes:
1. If the calibration of the rate or total display
defined as the source for the 4/20mA output
is changed, the 4/20mA output will
automatically be set to give a constant
3.5mA output irrespective of the display.
The 4/20mA output should always be
reconfigured following reconfiguration of the
source display.
2. If the Counter and the 4/20mA current sink
output are powered from separate supplies,
the 4/20mA output current will continue to
flow when the Counter supply fails or is
turned off. Powering both from a common
supply eliminates this effect.
10.6 Backlight
The BA367NE Counter can be supplied with a
factory fitted backlight that produce green
illumination enhancing display contrast and enabling
it to be read at night or in poor lighting conditions.
The backlight is internally powered from the
instrument power supply so that no additional wiring
is required, but the instrument supply current
increases.
Current consumption
Without backlight 10.0mA
Addition for backlight 22.5mA
Addition with terminals 3 & 4 linked 6.0mA
_______
Total current 38.5mA
Appendix 1
Dust certification
A1.0 ATEX dust certification
In addition to ATEX Ex nA certification permitting
installation in explosive gas atmospheres which is
described in the main section of this instruction
manual, all BA367NE Counters have ATEX dust
ignition protection by enclosure certification Ex tc
permitting installation in combustible dust
atmospheres. The front panel push button switches
are non incendive and have been certified
intrinsically safe Ex ic without the need for Zener
barriers or galvanic isolators.
This appendix describes ATEX installations in
explosive dust atmospheres conforming with
EN 60079-14
Electrical installations design,
selection and erection . When designing systems for
installation outside the UK the local Code of Practice
should be consulted.
The Counter’s Ex tc dust input and output safety
parameters are identical to the Ex nA gas
parameters, therefore all the electrical circuits shown
in the main section of this manual may also be used
for dust applications.
A1.1 Zones, and Maximum Surface
Temperature
The BA367NE has been ATEX dust certified
Group II, Category 3D
Ex ic tc IIIC T80ºC Dc -40
≤ Ta ≤ 60°C
When connected to a suitable system the Counter
may be installed in:
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 indicator 155
°
C
up to 5mm thick
Dust layer on indicator Refer to
over 5mm thick. EN 60079-14
At an ambient temperature between -40 and +60°C
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