32
Step 8
Enter the flowmeter K-factor
K-factor is the number of pulses that a
flowmeter produces per unit volume of
flow. The Rate Totaliser pulse input is
divided by
FACtor
, which is adjustable
between 0.0001 and 99999. When set
to the K-factor of the flowmeter
factor
converts the flowmeter output into
engineering units ready for further
scaling to produce the required rate and
total flow displays.
Using the
&
or
*
push button select
FACtor
from the configuration menu and
press
(
to show the existing value with
one digit flashing. Enter
105
using the
&
or
*
push button to adjust the
flashing digit and the
(
button to
transfer control to the next digit and to
position the decimal point. Finally return
to the
FACtor
prompt in the configuration
menu by pressing
)
.
The output from
FACtor
will now be in litres which may be
scaled to produce required rate and total
displays.
See 6.12
Step 9
Enter the total scale factor
The Total Scale Factor
5CALE . t
is a
dividing factor adjustable between
0.0001
and
99999
that enables total flow to be
displayed in the required engineering
units. In this example the total flow
display is required in cubic metres.
There are 1,000 litres in a cubic metre so
5CALE-t
should be set to
1000.
Using the
&
or
*
push button select
5CALE . t
from the configuration menu
and press
(
to reveal the existing value
with one digit flashing. Enter
1000
using
the
&
or
*
push button to adjust the
flashing digit and the
(
button to
transfer control to the next digit and to
position the decimal point. Finally,
return to the
5CALE
.
t
prompt in the
configuration menu by pressing
)
. The
total flow display is independent of the
rate display. See 6.13
Step 10 Enter the rate scale factor
5CALE . r
is a dividing factor adjustable
between
0.0001
and
99999
that enables
the flow rate to be displayed in the
required engineering units. The rate
display timebase is determined by
t-bA5E
that is adjusted in Step 11.
In this example the rate of flow display
is required in imperial gallons.
FACtor
,
which was adjusted in Step 8 of this
example produces an output in Litres
that must be converted to imperial
gallons. There are 4.5461 Litres in an
imperial gallon so
5CALE . r
should be
adjusted to 4.5461
Using the
&
or
*
push button select
5CALE . r
from the configuration menu
and press
(
to reveal the existing
value with one digit flashing. Enter
4.5461 using the
&
or
*
push button
to adjust the flashing digit and the
(
button to transfer control to the next
digit and to position the decimal point.
Finally return to the
5CALE . r
prompt in
the configuration menu by pressing
)
.
The flow rate display is independent of
the total flow display.
See 6.14
Step 11 Enter the rate timebase
The rate timebase determines whether
flow rate is displayed per second, per
minute or per hour. In this example
gallons per hour are required.
Using the
&
or
*
push button select
t-bA5E
from the configuration menu
and press
(
. Again using the
&
or
*
push button select
tb-3600
from
the three options which will multiply the
rate display by 3600. Return to the
t-bA5E
prompt in the configuration
menu by pressing
)
.
See 6.15
Step 12 Adjust the display filter
The digital display filter has two
independent adjustable parameters
enabling the rate display response to
be tailored for optimum performance.
The filter parameters are controlled by
a two digit number. The first digit
defines the amount of filtering applied
to the display, for initial configuration it
is recommended it is set to
2
which is a
time constant of 4.3 seconds. The
second digit controls jump-out following
a step input change and it is
recommended that this is initially set
to
0
.
After
configuration
during
commissioning both parameters should
be adjusted experimentally to provide a
stable display with an acceptable step
response.
Summary of Contents for BA334NG
Page 1: ...Issue 5 9th July 2019 BA334NG Ex nA and Ex tc Externally powered Rate Totaliser Issue 5 ...
Page 18: ...18 ...
Page 19: ...19 ...
Page 28: ...28 ...
