BEKA BA567E-SS, Руководство пользователя

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8. ACCESSORIES
Accessories for the BA567E-SS Counter are shown
below, all except the scale card are factory fitted and
should be specified when the instrument is ordered:
Scale card
Tag number
Backlight 1
Isolated pulse output
2
or
Isolated 4/20mA output 2
or
Isolated dual alarms 2
Notes:
1. Internally powered
2. Only one of the three output options can
be fitted to a BA567E-SS.
8.1 Scale card
The BA567E-SS has a window on the right hand
side of the display through which to view a scale
card showing the units of measurement such as
Strokes or Metres. New Counters are fitted with a
scale card showing the units of measurement
specified when the instrument was ordered, if the
units are not specified a blank scale card will be
fitted. A pack of scale cards pre-printed with
common units of measurement is available as an
accessory. These can easily be fitted on-site to the
Counter without opening the instrument enclosure or
removing it from the panel, See section 4.5 of this
instruction manual.
Custom scale cards for applications requiring less
common units of measurement are also available.
8.2 Tag information
A tag number or application information can be
printed onto the rear panel adjacent to the terminals.
This information is not visible from the front of the
instrument after installation.
8.3 Alarms
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
factory fitted dual solid state single pole alarm
outputs that may be independently configured as
high or low, rate or total alarms with normally open
or normally closed outputs.
Configurable functions for each alarm include
adjustable setpoint, alarm delay time and alarm
silence time. Hysteresis may be applied to rate
alarms.
CAUTION
Alarm outputs should not be used for
critical safety applications such as a shut
down system.
When the BA567E-SS power supply is turned off or
disconnected, alarm outputs will open irrespective of
whether normally open or normally closed outputs
have been selected. When designing a system an
open output should therefore be chosen for the
alarm condition.
Alarm annunciators on the instrument display
indicate the status of each alarm. If an alarm delay
or silence time has been selected the annunciator
will flash during the delay or silence period.
The BA567E-SS internal counters are up-dated and
compared with the alarm setpoint twice per second,
irrespective of the display update time selected.
This may result in an alarm being delayed for up to
half a second after the rate or total has exceeded the
setpoint.
8.3.1 Solid state output
Each alarm has a galvanically isolated single pole
solid state switch output as shown in Fig 14. The
outputs are polarised and current will only flow in
one direction. Terminals A1 and A3 should be
connected to the positive side of the supply.
Ron = less than 5

+ 0.7V
Roff = greater than 1M

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
The solid state output of each alarm may be used to
switch any circuit with parameters equal or less than:
V = 30V
I = 200mA
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