BEKA BA567E-SS, Руководство пользователя

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To adjust an alarm setpoint select
5P1
x or
5P 2
x and
press
(
which will reveal the current setting. The
flashing digit of the setpoint may be adjusted using
the
&
and
*
push buttons and the
(
button to
move control to the next digit. When the required
setpoint has been entered, pressing
)
will return
the display to the
5P1
x or
5P 2
x prompt from which
the other setpoint may be selected, or the instrument
may be returned to the display mode by pressing
)
again.
Note: Direct access to the alarm setpoints from
the display mode is only available when
the
AC5P
menu is enabled - see section
8.3.12
8.4 Pulse output
Only one of the following accessories may be
fitted: dual alarms, pulse output or 4/20mA
output.
The BA567E-SS Counter can be supplied with a
factory fitted opto-isolated solid state pulse output.
The output is an open collector having the following
electrical parameters:
Ron = 60

+ 3V
Roff = 1M
Imax = 10mA
The output pulse may be a duplicate of the input
pulse for re-transmission applications, or it may be
derived from the total display. When derived from
the total display the output pulse frequency may be
divided and the output pulse width defined.
The retransmitted RTx annunciator on the
instrument display shows the status of the
retransmitted pulse output. Annunciator activation
depends upon the setting of
5ource
in the pulse
output configuration menu.
5caled:
Annunciator activated each time pulse output
open collector is
on , i.e. Ron is less than
60 Ω + 3V.
direct:
Annunciator continuously activated
8.4.1 System design
The BA567E-SS Counter's optional pulse output is a
passive circuit i.e. not powered, but it is totally
isolated from all other Counter circuits. Terminals
P1 and P2 may be connected to any other
instrument with an open collector input.
Fig 13 shows how a voltage pulse may be generated
that could be used to drive a remote counter. The
positive terminal of the pulse output circuit P1 is
connected to the BA567E-SS Counter’s positive
supply terminal 1 at the instrument. When an output
pulse occurs and the open collector output 'closes',
P2 is connected to P1 and a pulse current flows
through resitor R1. The current flowing in the circuit
is determined by resistor R1 which should be chosen
to limit the pulse output current to less than 10mA.
For a 24V supply R1 should be greater than 2,200
Ω .
Fig 13 Generating a voltage pulse output
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