BEKA BA337E, Manual

Page: 35 / 61

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.
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