BEKA BA524D, Manual

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The selected break-point can be changed using the
Up and Down buttons. When the required
break-point has been selected press P . Set the
indicator input current to the exact value at which
the break-point is to occur, and adjust the indicator
display using the
Up and Down buttons and P to
move between digits. When the required display
has been set, press
E to enter the information and
return to the sub-menu from which another
break-point can be selected.
Repeat this procedure for each break-point, and
then return to the main menu by pressing
E twice.
8.3.2 Calibration using internal references
This function enables the break-points to be
adjusted without the need for an accurate external
current source. Throughout calibration the
indicator input current may be any value between 4
and 20mA.
The accuracy of this method depends upon the
accuracy of the internal references which should be
calibrated periodically against a traceable external
current source with a resolution of at least 0.4µA.
See section 5.7.2
The number of break-points required should first be
entered using the Add and dEL functions. In both
these functions the indicator initially displays the
current break-point and the total number of
break-points being used. e.g.
5 13
current total number of
break-point break-points
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
subsequent break-points is increased by
one.
'dEL' Remove a break-point
Removes the displayed break-point and
joins the preceding break-point to the
following break-point with a straight line.
The identification of subsequent
break-points is decreased by one.
Display Description of function
'InPut' 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 display at break-point
Enables the indicator display at each
break-point to be defined.
Select 'SEt' from the main menu and press P once
to enter the 'Add' function, and again to reveal the
current and total number of break-points. Each
subsequent operation of the
P push-button will
introduce an additional break-point. When adding
a break-point to a calibrated indicator, the insertion
position can be selected using the
Up and Down
push-buttons.
The delete break-point function 'dEL' operates in a
similar manner to the 'Add' function described
above.
When the required number of break-points has
been entered, return to the sub-menu by pressing
E. The indicator will display 'Add' or 'dEL'
depending upon the last function used. The
required indicator display at each break-point can
now be entered, followed by the input current at
which each break-point occurs.
To enter the required display at any break-point
select 'diSP' from the sub-menu and press
P which
will select the first break-point '0 n', where 'n' is the
total number of break-points selected. The
selected break-point can be changed using the
Up
and Down buttons. When the required break-point
has been selected press P to reveal
the existing display. Using the Up and Down
buttons and P to move between digits set the
revised display. Press E to return to the sub-menu
from which another break-point can be selected.
Repeat this procedure for all the break-point
displays to be changed, and then return to the
'diSP' prompt in the sub-menu by pressing
E.
To enter the input current at which each
break-point occurs select 'InPut' from the sub-menu
and press
P which will select the first break-point
'0 n'. The selected break-point can be changed
using the
Up and Down buttons. When the
required break-point has been selected, press P to
reveal the input current at which the break-point
occurs. Using the
Up and Down buttons and P to
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