BEKA BA654D, Руководство пользователя

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5
If no items are contained in the menu
the operator can only start, pause
and stop a batch. Inclusion of the
Select Batch function allows the
operator to select the batch setpoint
from one of nine pre-entered values.
To aid identification, each setpoint
may be identified by a name having
up to sixteen digits.
If included in the menu, the Batch
Size function allows the adjustment
of all the pre-entered batch setpoints.
Batch History shows the size of the
last ten batches which have been
completed.
The Configure function provides
operator access to the batch
controller configuration menus
described in section 5. Entry to
these menus is protected by an
external security link between
terminals 18 and 19 and an optional
four digit security code.
3. SYSTEM DESIGN
The BA654D is a versatile instrument that may
be used with most flowmeters having a pulse
or 4/20mA output. Fig 3 illustrates the basic
circuit that is used for all installations.
Although the BA654D batch controller will
operate from a wide range of input sources,
only one source or transducer may be
connected at any time.
Fig 3 Basic batch controller circuit
3.1 Power supply
Any dc power supply having an output
between 20 and 36 volts that is capable of
supplying 95mA may be used to power the
BA654D. The output ripple must not cause the
instantaneous voltage to drop below 20V.
The batch controller inputs and outputs are
galvanically isolated thus allowing multiple
batch controllers to be operated from a
common power supply. Similarly, if required
the power supply may be earthed. If a
common or earthed supply is used, the batch
controller inhibit and security link terminals,
and the optional external switch terminals
should only be connected to electrically
isolated switch contacts. i.e. they should not
be earthed or connected to other circuits.