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1. DESCRIPTION
The BA544D is a 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.
Housed in a robust IP66 glass reinforced
polyester (GRP) enclosure with an armoured
glass window, the BA544D 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
BA544D. The instrument accepts a pulse input
which, after scaling is displayed as the total
number of pulses received and their rate on
two separate displays. When connected to a
pulse output flowmeter the BA544D will provide
an accurate display of total flow and the rate of
flow. The BA544D 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 BA544D contains an internal replaceable
battery that will power the instrument for up to
five years. Battery life depends upon how the
BA544D is programmed and the pulse input
frequency. Replacement BA491 batteries may
be installed with the BA544D in situ.
Fig 1 Simplified block diagram of BA544D
2.1 Controls
The BA544D 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 5.13
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 8.2
Summary of Contents for BA544D
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