BEKA BA334D, Manual

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1. DESCRIPTION
The BA334D is an intrinsically safe, externally
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 BA334D has been certified intrinsically
safe by European Notified Body Intertek
Testing Sevices (ITS) to the ATEX Directive
94/9/EC for use in explosive gas and
combustible dust atmospheres.
ATEX dust certification is an option – see
Appendix 1.
For use in the USA a version having FM
intrinsic safety and nonincendive approval is
available - see Appendix 2.
Housed in a robust IP66 glass reinforced
polyester (GRP) enclosure with an armoured
glass window, the BA334D 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
BA334D. The instrument accepts pulses from
a single source and after scaling displays the
total number of pulses received and their rate
on separate displays. When connected to a
pulse output flowmeter the BA334D will provide
an accurate display of total flow and the rate of
flow.
The BA334D has two sets of input terminals for
connection to high or low level voltage pulses,
a switch contact, an open collector output or to
a two wire proximity detector. The instrument
may therefore be used with almost any type of
pulse output flowmeter. The total display
may be reset to zero by a remote switch
contact, the internal switches or via the
optional keypad on the outside of the
instrument.
Optional accessories enable the flow rate to be
transmitted to other equipment as an isolated
4/20mA analogue signal and the total flow to
be transmitted as a pulse signal. Optional
alarms, which may be programmed to function
on the rate or total displays, further extend the
instruments applications.
Fig 1 Simplified block diagram of BA334D
2.1 Initalisation
Each time power is applied to the instrument
initalisation is performed. After a short delay
the following display sequence occurs:
All segments of the display are activated
for about 2 seconds.
The product firmware part number and
version number are displayed for about 2
seconds.
Rate display and totaliser start to
function
using calibration information
stored in the instrument's permanent
memory.
2.2 Controls
The BA334D 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 instrument cover.
In the display 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.