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1. DESCRIPTION
The BA344D is an intrinsically safe, battery
powered pulse input rate totaliser primarily
intended for use with flowmeters. The
instrument simultaneously displays the rate of
flow and the total flow in engineering units on
two separate displays.
The BA344D complies with the European
ATEX Directive 94/9/EC and has been certified
intrinsically safe for use in explosive gas and
combustible dust atmospheres by Notified
Body Intertek Testing Services (ITS).
ATEX dust certification is an option - See
Appendix 1.
Housed in a robust IP66 glass reinforced
polyester (GRP) enclosure with an armoured
glass window, the BA344D is surface
mounting, or may be pipe mounted using one
of the accessory kits. A stem mounting kit is
also available allowing direct mounting onto a
flowmeter conduit entry.
2. OPERATION
Fig 1 shows a simplified block diagram of a
BA344D. The instrument accepts pulses
which, after scaling, are shown on two
separate displays as the total number of pulses
received and their rate. When connected to a
pulse output flowmeter the BA344D will provide
an accurate display of total flow and the rate of
flow. The BA344D has two sets of input
terminals allowing connection to high or low
level voltage pulses, switch contacts or to an
open collector output, it may therefore be used
with most flowmeters. The total display may
be reset to zero by a remote switch contact,
the internal switches or via the optional
external keypad.
Optional alarms, which may be programmed to
function on the rate or total displays, further
extend the applications of this instrument.
The BA344D contains an internal replaceable
battery that will power the instrument for up to
five years. Battery life depends upon how the
BA344D is programmed, and the pulse input
frequency. A replacement BA491 battery may
be installed without removing the BA344D from
the hazardous area.
Fig 1 Simplified block diagram of BA344D
2.1 Controls
The BA344D is controlled and calibrated via
four push-button switches which are located
behind the instrument control cover, or as an
option on the outside of the control cover. In
the operating mode, i.e. when the instrument is
displaying rate and total flow, the switch
functions are:
Description of Switch Functions
E+ Down
While these buttons are pushed the
total display will show the least
significant eight digits of the grand
total, and the grand total
annunciator will be activated.
E+Up
While these two buttons are pushed
the total display will show the most
significant eight digits of the grand
total and the grand total annunciator
will be activated.
Down
The total display is reset to zero
+Up
when these two push-buttons are
operated simultaneously for two
seconds.
This function may be turned on or
off from within the programme
menu.
See section 6.13
P
While these buttons are pushed the
+Down
instrument will display the firmware
part number and version number.
Note
: When optional alarms are fitted the
push-buttons may be programmed to have
alternative functions – see section 9.2
Summary of Contents for BA344D
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