BEKA BA304NG, Руководство пользователя

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4
2.1 Controls
Both models are controlled and calibrated via four
front panel push buttons. In the display mode i.e.
when the indicator is displaying a process variable,
these push buttons have the following functions:
(
While this button is pushed the
indicator will display the input current
in mA, or as a percentage of the
instrument span depending upon how
the indicator has been configured.
When the button is released the
normal display in engineering units
will return. The function of this push
button is modified when optional
alarms are fitted to the indicator.
&
While this button is pushed the
indicator will display the numerical
value and analogue bargraph* the
indicator has been calibrated to
display with a 4mA
Φ input. When
released the normal display in
engineering units will return.
*
While this button is pushed the
indicator will display the numerical
value and analogue bargraph* the
indicator has been calibrated to
display with a 20mA
Φ input. When
released the normal display in
engineering units will return.
)
No function in the display mode
unless the tare function is being used.
(
+
&
Indicator displays firmware number
followed by version.
(
+
*
Provides direct access to the alarm
setpoints when the indicator is fitted
with optional alarms and the
AC5P
access setpoints function has been
enabled.
(
+
)
Provides access to the configuration
menu via optional security code.
Note: * BA324NG only
Φ If the indicator has been calibrated
using the CAL function, calibration
points may not be 4 and 20mA.
3. CERTIFICATION
Both models have ATEX and IECEx gas and dust
certification. This section of the instruction manual
describes ATEX gas certification. ATEX dust
certification is described in Appendix 1 and IECEx
approvals are described in Appendix 2.
3.1 ATEX Ex nA certification
Notified Body Intertek Testing and Certification Ltd
have issued both models with a common EC-Type
Examination Certificate number ITS11ATEX47255.
This confirms compliance with harmonised
European standards and it has been used to
confirm compliance with the European ATEX
Directive for Group II, Category 3G equipment,
Ex nA ic IIC T5 Gc Ta = -40 to +70°C. The
indicators carry the community mark and, subject
to local codes of practice, may be installed in any
of the European Economic Area (EEA) member
countries. ATEX certificates are also acceptable
for installations in Switzerland.
This section of the instruction manual describes
ATEX installations in explosive gas 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.
3.2 Zones, gas groups and T rating
Both indicators have been certified Ex nA ic IIC T5.
When connected to a suitable system they may be
installed in:
Zone 2 explosive gas air mixture not
likely to occur, and if it does
will only exist for a short time.
Be used with gases in groups:
Group A propane
Group B ethylene
Group C hydrogen
In gases that may be used with equipment having
a temperature classification of:
T1 450°C
T2 300°C
T3 200°C
T4 135°C
T5 100°C
At ambient temperatures between -40 and +70°C.
This allows both models to be used with most
common industrial gases except carbon disulphide
and ethyl nitrite which have an ignition temperature
of 95°C.