BEKA BA337E, Руководство пользователя

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1. DESCRIPTION
These intrinsically safe, one input rate totalisers are
primarily
intended for use with pulse output
flowmeters. The instruments simultaneously display
the rate of flow and the total flow in the same or
different engineering units on two separate displays.
They are controlled and configured via the four front
panel push buttons, a user defined four digit code
may be entered to prevent accidental access to the
instrument's configuration menu.
The two models are electrically similar, but have
different size displays and enclosures. The available
factory fitted accessories also vary.
Model Displays Bezel size
BA337E 8 digits 9mm high 96 x 48mm
6 digits 6mm high
BA338E 8 digits 18mm high 144 x 72mm
6 digits 12mm high
This instruction manual supplements the abbreviated
instruction sheet supplied with each instrument.
Both models have been certified intrinsically safe for
use in gas hazardous areas by Notified Body Intertek
Testing and Certification Ltd and comply with the
European ATEX Directive 2014/34/EU.
For international applications both models also have
IECEx certification which is described in Appendix 1.
For applications in the USA and Canada both models
have ETL and cETL certification which is described in
Appendix 2.
2. OPERATION
Fig 1 shows a simplified block diagram of the BA337E
and BA338E Rate Totalisers. The instruments can
accept pulses from most types of flowmeter
transducers.
When connected to a pulse output
flowmeter the BA337E and BA338E will provide an
accurate display of the rate of flow and the total flow
in the same or different engineering units.
The
internal lineariser, which can have up to sixteen
straight-line
segments, may be calibrated to
compensate for flowmeter non-linearity.
The BA337E and BA338E have a single pair of input
terminals for connection to all types of transducer.
When counting pulses from a transducer requiring
energising, such as a switch contact, open collector or
a two wire proximity detector, an external link between
terminals 3 and 4 supplies power to the transducer
input terminals.
Factory fitted accessories include an internally
powered display backlight, dual alarms and an
isolated 4/20mA output which may be configured to
retransmit the rate or total display.
The larger BA338E Rate Totaliser is always supplied
with an isolated pulse output which can be
configured to synchronously retransmit the pulse
input, or the flow total. This output is only available
on the smaller BA337E Rate Totaliser as an option.
Factory fitted optional accessories for the two
models are shown below:
BA337E BA338E
96 x 48mm 144 x 72mm
Backlight Backlight
Isolated dual alarms
*
Isolated dual alarms
or
Isolated 4/20mA output
*
Isolated 4/20mA output
or
Isolated pulse output
*
*Only one output option Isolated pulse output
may be fitted to BA337E always fitted to BA338E
Fig 1 BA337E and BA338E block diagram
2.1 Initialisation
Each time power is applied to the Rate Totaliser
initialisation is performed. After a short delay the
following display sequence occurs:
All segments of the display are activated
Instrument starts functioning using the
configuration information stored in permanent
memory.
Unless total and grand total
displays have been reset to zero, new flow will
be added to the existing totals.
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