BEKA BA317NE, Manual

Page: 34 / 40

To comply with the requirements of
EN 60079-14
Electrical installations design, selection
and erection , each of the wires entering the
hazardous area should be individually fused and
contain a means of isolation. These two requirements
may be satisfied by installing DIN rail mounted
terminals incorporating a fuse which can easily be
removed as shown in Fig 2 to provide isolation. Clear
identification of, and easy access to the means of
isolation is essential for their effective use. It is also
necessary to ensure that the maintenance procedure
makes sure that unauthorised re-closure of the
switches does not occur. It is not considered
necessary to have a means of isolation or electrical
protection for cable screens.
For some application Ex nA instrumentation energised
by a current limited power supply or instrument that
can be switched off, is often considered adequate and
to comply with the requirements of the standard.
9.5.2 Pulse output configuration:
PuL5E oP
When the BA317NE Tachometer is supplied with a
factory fitted pulse output the configuration menu is
extended as shown in Fig 18 to include the pulse
output sub-menu
PuL5E . oP.
The pulse output sub-menu allows the source of the
output pulse to be selected in the
5ourCE
sub-
function. For re-transmission applications the
output pulse may be a synchronous duplicate of the
input pulse by selecting
dirECt
in the
5ourCE
sub-
function. When
5CALEd
is selected, two additional
functions,
diVidE
and
durAtion
are introduced
enabling the input pulse frequency to be divided to
produce the output pulse frequency, and the output
pulse width (duration) to be lengthened.
Fig 18 Pulse output configuration sub-menu
9.5.3 Enable pulse output:
EnbL
This function allows the pulse output to be disabled
or enabled without altering any of the pulse output
parameters. Using the
&
or
*
push button select
EnbL
in the pulse output sub-menu and press
(
to
reveal the existing setting
on
or
oFF
. The function
can be changed by pressing the
&
or
*
push
button followed by the
)
button to return to
EnbL
.
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