BEKA BA354NE, Руководство пользователя

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The delete break-point sub-function 'dEL' operates
in exactly the same way as the 'Add' sub-function
described above. Once within the ‘dEL’ sub-
function each time the
P button is pressed a break-
point is removed. When deleting a break-point from
a calibrated Rate Totaliser, the break-point to be
deleted can be selected using the
▲ and ▼ push
buttons. The minimum number of break-point is 2,
break-points '0
: 1' and '1 : 1'.
When the required number of linearising break-
points has been entered, return to the linearisation
sub-menu by pressing
E . The Rate Totaliser will
display the 'Add' or 'dEL' prompt depending upon the
last function used. Using the 'Pts' sub-function the
input current at which each break-point occurs and
the corresponding rate display may now be defined.
Using the ▲ or ▼ button select the 'PtS' function
in the sub-menu and press P to enter the function
which will display the first break-point '0 : n', where n
is the total number of linearising break-points
entered – see Fig 8. The selected linearising break-
point can be changed using the
▲ and ▼ buttons.
When the required linearising break-point has been
selected set the Rate Totaliser input current to the
exact value at which the break-point is required and
press
P* . Using the ▲ and ▼ buttons and the P
button to move between digits, enter the required
Rate display at this break-point. When set as
required, press the
E push button to enter the
required rate display and return to the sub-menu
from which the next beak-point can be selected.
When all the break-points have been calibrated
pressing
E twice will return the Rate Totaliser to the
‘CAL’ function in the configuration menu.
Note: * The Rate Totaliser input current must be
adjusted to the required value before the
P button is operated to enter the required
indicator display.
Error message
If during calibration the Rate Totaliser
displays a 'FAiL' error message the current
at which the selected break-point is being
set is not above the proceeding break-
point or is not below the following break-
point.
7.1.1 Example, Adding break-points to a new
Rate Totaliser
When adding break-points to a new Rate Totaliser,
or to a lineariser following resetting to the factory
defaults using the 'LtAb' function described in
section 6.19, each additional break-point should be
added before the highest existing breakpoint. The
first additional break-point should be added before
the default break-point '1
: 1' which will result in a
display of '1 : 2'. If more new break-points are
required, using the ▲ button select the new highest
break-point '2 : 2' and add the second additional
break-point by operating the P push button which
will result in a display of '2 : 3'. Repeat the sequence
until the required number of break-points has been
entered.
The input current and at which each break-point
occurs and the corresponding indicator display may
now be entered as described above.
7.2 Lineariser calibration using the internal
reference.
The ‘SEt’ function enables the lineariser to be
calibrated without the need for an accurate external
current source. Throughout the calibration the
indicator input current may be any value between 4
and 20mA.
The ‘SEt’ functions contains four sub-functions.
Display Description of function
'Add' Add a break-point
Adds a new break-point before the
displayed break-point. The calibration of
existing break-points is not changed, but
the identification number of all
subsequent break-point is increased by
one.
'dEL' Remove a break-point
Removes the displayed break-point and
joins the preceding segment to the
following segment with a straight line.
The identification number of all
subsequent break-points is decreased by
one.
'in' Defines the current at which break-
point occurs.
Enables the required current at each
break-point to be defined without having
to input an accurate input current to the
indicator.
'diSP' Defines indicator display at break-
point.
Enables the indicator display at each
break-point to be defined.
The number of break-point required should first be
entered using the 'Add' and 'dEL' sub-functions. In
both these sub-functions the indicator initially
displays the current break-point and the total
number of break-point being used as shown below.
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