To add a break-point using the
▲
or
▼
button select
'SEt' from the configuration menu and press
P
which
will result in the
'Add' sub-function prompt being
displayed. To enter the sub-function press
P
which
will reveal the current break-point and the total
number of break-points which have already been
entered. When adding a break-point the insertion
position can be selected using the
▲
and
▼
push
buttons followed by
P
push button to insert the
additional break-point. In previously uncalibrated
linearisers each new break-point should be added in
front of the highest existing break-point, if this
sequence is not followed a 'FaiL' message will occur
when the breakpoints are calibrated. See example in
section 7.2.1.
The delete break-point, sub-function 'dEL' operates in
exactly the same way as the 'Add' sub-function
described above. Once within the ‘dEL’ function each
time the
P
button is pressed a break-point is removed.
When deleting a break-point from a calibrated
indicator, 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-point
has been entered, return to the linearisation sub-menu
by pressing
E
.
The indicator will display the 'Add' or
'dEL' prompt depending upon the last sub-function
used. The indicator input current and corresponding
indicator display at each break-point can now be
entered using the ‘in’ and ‘diSP’ sub-functions.
Using the
▲
or
▼
button select 'in' from the sub-menu
and press
P
which will reveal the starting point for the
first segment '0
:
n', where n is the total number of
break-point entered. Press
P
and use the
▲
and
▼
buttons and the
P
button to move between digits, to
enter the input current in milliamps at which the first
break-point is required, usually 4.000mA. When set
as required, press
E
to return to the ‘0
:
n’ prompt from
which the next break-point can be selected using the
▲
and
▼
buttons. When the required break-point has
been selected press
P
and enter the indicator input
current at which this break-point is required using the
▲
and
▼
buttons and the
P
button to move between
digits,. Repeat this procedure until the indicator input
current at all the break-points has been defined and
then return to the ‘in’ sub-function by pressing the
E
button.
The corresponding indicator display at each of the
break-points can now be defined using the ‘diSP’ sub-
function Using the
▲
and
▼
buttons select the
‘diSP’ sub-function and press
P
which will reveal the
starting point for the first break-point '0
:
n', where n
is the total number of break-points entered. Press
P
and use the
▲
and
▼
buttons and the
P
button to
move between digits, to enter the required indicator
display at the first break-point. When set as required,
press
E
to return to the ‘0
:
n’ prompt from which the
next break-point can be selected using the
▲
or
▼
buttons. When the required break-point has been
selected press
P
and set the required indicator
display at this break-point.
Repeat this procedure until the indicator display at
all the break-points has been defined and then
return to the ‘SEt’ function in the configuration
menu by pressing the
E
button twice.
Error message
If during calibration the indicator 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.
7.2.1 Example
Adding break-points to a new indicator
When adding break-points to a new indicator, or to
a lineariser following resetting to the factory
defaults using the 'LtAb' function described in
section 6.11, 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.
7.3 Under and over-range
The lineariser does not change the under and
over-range indication described in section 6.12.
At input currents below that specified for the first
break-point '0
:
n', the indicator will continue to use
the specified slope of the first segment.
At input currents above that specified for the last
break-point 'n:n', the indicator will continue to use
the slope specified for the last lineariser segment.
7.4 Lineariser default configuration
When the lineariser is reset to the factory defaults
using the ‘LtAb’ function described in section 6.11,
the defaults conditions are:
Indicator display
BA307E-SS BA327E-SS
First break-point '0
:
1' 4mA 0.0
0.00
Second break-point '1
:
1' 20mA 100.0
100.00
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