BEKA BA384E, Руководство пользователя

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11.4.3 Configuration
When a Rate Totaliser is supplied with an optional
4/20mA output the configuration menu is extended
as shown in Fig 20. The 4/20mA output sub-menu
is accessed via the
4-20 oP
function that is located
between the
Pul5E op
and
CLr Gtot
functions.
The 4/20mA output sub-menu allows the 4/20mA
output to be controlled by the composite rate or the
composite total display.
Fig 20 4/20mA output configuration sub-menu
11.4.4 Access 4/20mA output sub-menu:
4-20 oP
Access the Rate Totaliser configuration menu as
described in section 6.2. Using the
&
or
*
push
button scroll though the menu until
4-20 oP
is
displayed, pressing
(
will then access the 4/20mA
output sub-menu which is shown in Fig 20.
11.4.5 Enable 4/20mA output:
Enbl
This function allows the 4/20mA current output to be
disabled or enabled without altering the calibration.
Using the
&
or
*
push button select
EnbL
in the
4-20 op
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
prompt in
the sub-menu.
11.4.6 Select rate or total source: ‘
4-20tYPE
The 4/20mA output current can represent the Rate
Totalisers composite rate or composite total display.
which must be defined before any other current
output functions are adjusted.
Using the
&
or
*
push button select
4-20tYPE
in
the 4/20mA output sub-menu and press
(
to reveal
the existing setting
totAL
or
rAtE
. The function can
be changed by pressing the
&
or
*
push button
followed by the
)
button to return to the
4-20tYPE
prompt in the sub-menu.
11.4.7 Display which corresponds to
4mA output:
4 . 000
The composite Rate Totaliser display which
corresponds to a 4.000mA output current is defined
by this sub-function. Using the
&
or
*
push
button select
4 . 000
in the 4/20mA output sub-menu
and press
(
which will reveal the existing display
with one digit flashing. The required display can be
entered using the
&
or
*
push button to adjust the
flashing digit and the
(
button to transfer control to
the next digit. When set as required press
)
to
enter the value and return to the
4 . 000
prompt in the
4/20mA output sub-menu.
11.4.8 Display which corresponds to
20mA output:
20 . 000
The Rate Totaliser composite display which
corresponds to a 20.000mA output current is defined
by this function. Using the
&
or
*
push button
select
20 . 000
in the 4/20mA output sub-menu and
press
(
which will reveal the existing display with
one digit flashing. The required display can be
entered using the
&
or
*
push button to adjust the
flashing digit and the
(
button to transfer control to
the next digit. 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 source of the 4/20mA
output is changed i.e. composite rate or
composite total display, the 4/20mA output will
automatically be set to give a constant 3.5mA
output irrespective of the display. The 4/20mA
output must always be reconfigured following
reconfiguration of the source display.
2: If the Rate Totaliser and the 4/20mA current
sink output are powered from separate
supplies, the 4/20mA output current will
continue to flow when the Rate Totaliser supply
fails or is turned off. Powering both from a
common supply but via separate Zener barriers
or galvanic isolators eliminates this effect.