16
Step 6
Enter the rate timebase
Select ‘t-bASE’ from the main menu
and press
P
to show the current
setting. In this example the rate
display is required in litres per hour.
Using the
Up
or
Down
button scroll
through the three options and
select ‘tb-3600’ which will multiply
the rate display by 3600. Return to
the ‘t-bASE’ prompt in the main
menu by pressing
E
.
Step 7
Adjust the rate filter
The rate display filter parameters
should be adjusted experimentally
after installation to provide a stable
rate display with an acceptable step
response.
During commissioning it is
recommend that initially the second
digit of the rate parameters is set to
0 (step response off) while the first
digit (amount of filtering) is adjusted
to provide acceptable rate display
stability. The second digit should
them be increased until acceptable
rate display stability is once again
achieved.
To adjust the filter parameters
select ‘FILtEr’ from the main menu
and press
P
to reveal the current
setting. The first digit will be
flashing and may be adjusted using
the
Up
or
Down
button. The
P
button will transfer control to the
second digit. When both are set as
required, return to the ‘FILtEr’
prompt in the main menu by
pressing
E
.
Note:
While adjusting the filter, the rate is
shown on the lower display so that
stability can be assessed.
Step 8 Enter the total scaling factor
The K factor of the flowmeter in this
example is 105.0 pulses per litre
and the total display is required in
cubic metres.
There are 1000 litres in a cubic
metre so the BA544D is required to
display 1 cubic metre for every 105
x 1,000 pulses received. ‘SCALE-t’
should therefore be set to 105,000
Select ‘SCALE-t’ from the main
menu and press
P
which will reveal
the current setting with one digit
flashing. To position the decimal
point, operate the
P
push-button to
move the flashing digit to the least
significant position. Pressing the
Up
and
Down
buttons
simultaneously will then remove the
decimal point.
Using the
Up
and
Down
buttons to
adjust each digit in turn and the
P
button to transfer control between
digits, enter 105000 - Finally
return to the 'SCALE-t' prompt in
the main menu by pressing
E
.
Step 9
Define clip-off
In this example totalisation is to be
inhibited at flow rates below 1 litre
per minute.
Select ‘CLIP-OFF’ from the main
menu and press
P
which will reveal
the clip-off threshold in litres per
hour i.e. the same units already
selected for the rate display. The
most significant digit of the display
will be flashing indicating that this
digit may be adjusted. Pressing P
five times will move the flashing
digit to the third least significant
position.
Using the
Up
and
Down
buttons set
the second least significant digit to
6 i.e. a clip-off threshold of 60 litres
per hour (1 litre per minute).
Finally return to the 'CLIP-OFF'
prompt in the main menu by
pressing
E
.
.
Step 10 Turn local reset on
In this example the operator needs
to reset the total display to zero by
pressing the
Up
and
Down
buttons
simultaneously. To activate the
local reset function select
‘LOC.rSEt’ from the main menu and
press
P
to display the current
setting. Pressing the
Up
or
Down
button will toggle the display
between ‘On’ and ‘OFF’. Select
‘On’ and press
E
to return to the
‘LOCrSEt’ prompt in the main
menu.
Summary of Contents for BA544D
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