15
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, which is the segment finishing point as
shown in Fig 8, 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 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 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 this break-point. Repeat this procedure
until the indicator input current at all the 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 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.
6.3 Lineariser error message
If an attempt is made to position a break-point at a
current which is not greater than the current of the
preceeding break-point, or at a current which is not
less than the current of the following break-point,
the error message ‘FaiL’ will be displayed. This
error message will also be displayed if an attempt
is made to position a break-point outside the
current range 3.8 to 21.0mA.
6.4 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), the indicator will continue to use
the specified slope of the first segment. Although
not guaranteed, most indicators will continue to
function normally with an input current between
1.8mA and 4mA, at lower currents the instrument
will display ‘LPLo’ before it stops functioning.
At input currents above that specified for the last
break-point, the indicator will continue to use the
slope specified for the last lineariser segment.
6.5 Lineariser default configuration
When the lineariser is reset to the default
conditions using the ‘rSEt’ reset function described
in section 6.11, the defaults conditions are:
BA504E BA524E
First break-point 4mA
0.0
0.00
Second break-point 20mA
100.0
100.00
