BEKA BA384E, Руководство пользователя

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10
Any certified intrinsically safe flowmeter may be
connected to a BA384G energised input providing
that:
a. The flowmeter is a certified intrinsically safe
device having input parameters equal to or
greater than:
Ui ≥ 10.5V dc
Ii ≥ 9.2mA dc
Pi ≥ 24mW
or complies with the requirements for
simple apparatus such as switch
contacts.
b. The flowmeter and associated wiring can
withstand a 500V rms insulation test to earth.
c. The flowmeter is located in the same
hazardous area as the BA384G.
d. Minimum operating voltage of flowmeter
incorporating a proximity detector should be
less than 7.5V.
The maximum capacitance and inductance that may
be safely connected to each energised input (link
connected) is:
Co = 2.4µF
Lo = 200mH
This is not restrictive as the combined capacitance
and inductance of most sensors and connecting
cable will be less than this.
3.6 Remote reset terminals
The BA384G total display may be reset to zero by
connecting the external reset terminals RS1 and
RS2 together for more than one second. The two
reset terminals have the following input and output
safety parameters:
Uo = 3.8V dc
Io = 1mA dc
Po = 1mW
Ui = 28V dc
Ii = 200mA dc
Pi = 0.84W
The equivalent capacitance and inductance between
them is:
Ci = 0nF
Li = 0µH
The maximum cable capacitance and inductance
that may be safely connected between the reset
terminals RS1 and RS2 is:
Co = 40µF
Lo = 1H
The reset terminals may be directly connected to
any mechanically operated switch located within the
same hazardous area as the BA384G. The switch
and associated wiring should be able to withstand a
500V rms insulation test to earth.
If the reset switch is required in the safe area a
Zener barrier or intrinsically safe relay is required to
transfer the contact closure into the hazardous area.
Almost any intrinsically safe relay with certification
permitting the contacts to be connected to
equipment in the hazardous area may be used. A
positive polarity Zener barrier may also be used as
shown in Fig 2. A diode return barrier is not suitable
for this application.
The BA384G may also be configured so that the
total display is reset to zero when the
&
and
*
push buttons are operated simultaneously for more
than three seconds. See 6.20
3.7 Certification label information
The BA384G product certification label is fitted in a
recess on the top outer surface of the instrument
enclosure. It shows the ATEX and IECEx
certification information plus BEKA associates name
and location and the instrument serial number.
Certification information from other authorities may
also be included.
BA384G Certification information label