BEKA BA526C, Manual

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Indicator to display '.020A'. Adjust the external
current calibrator to 20.000mA and again press
P . The indicator will display 'Ent' when the 20mA
reference has been updated and will then return tto
the '.020A' prompt. Two operations of the
E button
will return the indicator display to 'Cond' in the
main menu.
The accuracy of the internal references, and hence
the display accuracy,
will depend upon the
accuracy of the external current source. With a
maximum span of 19999 the indicator has a
display
resolution of 0.8µA, we therefore
recommend that the accuracy of the external
current source used for calibration is greater than
0.4µA.
5.11 Function of the P push-button:
C - - P
This parameter defines the function of the P push-
button when the indicator is in the display mode.
While the button is operated the digital display will
show the input current in milliamps, or the input
current as a percentage of the span.
The
analogue display continues to operate normally
while the
P button is operated.
To check or change the parameter select ' C -
-P' from the main menu and press
P to reveal the
current setting. Pressing the Up or Down button
will toggle the setting between '4-20' the current
display and 'PC' the percentage display. When set
as required press
E to return to the main menu.
Accuracy of the current display depends upon the
accuracy of the internal references which should
be periodically calibrated - see section 5.10.2
The function of the P push-button changes when
either or both alarms are enabled.
5.12 Null display function: null
This function enables the BA526C analogue
bargraph to operate as a deviation indicator
displaying the difference between the input current
and a specified reference.
To activate this function select 'null' from the main
menu and press
P . Pressing the Up or Down
button will toggle the function between 'OFF' and
'On', when set as required press
E to return to the
main menu.
Fig 7 Configuration of anolouge bargraph