BEKA BA527C, Manual

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To gain access to the security code link, remove
the instrument terminal block(s) by gently pulling.
Unscrew the four corner screws securing the rear
panel and lift off the panel which will reveal the link
as shown in Fig 7.
Fig 7 Location of security code override link
5.10 Over and under-range
If the indicator display range is exceeded, the four
least significant digits will be blanked. Under-range
is indicated by '-1' and over-range by '1'. Under
and over-range are also indicated if the input
current falls below approximately 3.5mA or rises
above approximately 21mA.
If the input current falls below 3mA the instrument
initialisation sequence is performed as described in
section 2.
6. Calibration Examples
The following examples illustrate the two ways in
which a BA527C or BA528C indicator may be
calibrated.
6.1 Using an external current source
A BA527C is required to display:
-50.0 with a 4mA input
1050.0 with a 20mA input
from a linear transducer. Maximum display
resolution is required, the frequency of the mains
supply is 50Hz and the existing security code is
1209. In the operating mode the indicator is
required to display the input current as a
percentage of span when the P push-button is
operated.
Step 1 Connect indicator to calibrator
Connect the indicator to an accurate
external current source. Terminal 1
positive. The indicator will
automatically perform the initialisation
routine described in section 2, and
then display the input current using
the existing calibration information.
Step 2 Enter programming mode
With an input current between 4 and
20mA put the indicator in the
programming mode by simultaneously
pressing
P and E . The indicator will
respond by displaying 'COdE'. Press
P to clear this prompt and set the
display to the security code 1209
using the
Up , Down and P push-
buttons. Pressing E will enter the
code, and after a few seconds during
which the decimal points will be
scrolled, the first parameter 'root' in
the main menu will be displayed.
Step 3 Square root extraction
With 'root' displayed, press P which
will reveal the root extractor status.
The root extractor can be turned on or
off by the
Up or Down buttons. Select
'OFF', and press E to return to the
main menu.