BEKA BA678C, Руководство пользователя, Страница: 22 / 27

9.3.1 Solid state output
Each alarm has a galvanically isolated single pole
solid state switch output as shown in Fig 9. The
outputs are polarised and current will only flow in
one direction.
Terminals 8 and 10 should be
connected to the positive side of the supply.
Ron = 5ohms + 0.6V
Roff = greater than 180k
Note: Because of the series protection diode some
test meters may not detect a closed alarm output.
Fig 9 Equivalent circuit of each alarm output
Fig 10 Typical alarm application
9.3.2 Alarm configuration
Alarm configuration may be performed via the HART

digital communication, see the BA47X/67X Indicating
Temperature Transmitter HART

Interface Guide
which may be downloaded from
www.beka.co.uk/manuals for details. Alternatively
configuration may be performed using the
configuration menu which is accessed via the front
panel push buttons, see Fig 3.
When a BA678C indicating temperature transmitter is
supplied with optional alarms the conditioning menu
is extended as shown in Fig 11.
The additional
alarm functions appear between 'bAr' and 'CodE' in
the configuration menu. For simplicity Fig 11 only
shows the additional sub-functions for alarm 1, but
alarm 2 has identical sub-functions.
The following table summarises each of the alarm
configuration
functions and includes a cross
reference to more detailed information. Again only
the functions for alarm 1 are listed, but alarm 2 has
identical functions.
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