BEKA BA384E, Manual

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6.15 Rate scale factor*:
5CALE . r-A
5CALE . r-A
is a dividing factor adjustable between
0.0001 and 99999 that enables the flow rate to be
displayed in the required engineering units. e.g. if
the output from
FACtor-A
is one pulse per litre and
the rate display is required in gallons,
5CALE . r-A
should be set to 4.5461 which is the number of litres
in an imperial gallons.
The units of the rate display are volume per unit of
time. The unit of time is the timebase of the
instrument which is determined by
t-bA5E
described in section 6.16.
To check or change the rate scale factor select
5CALE . r-A
from the configuration menu and press
(
which will reveal the existing value with one digit
flashing. The value of the flashing digit may be
changed by pressing the
&
or
*
button. When
this digit has been adjusted as required, pressing
(
will transfer control to the next digit. When all the
digits have been adjusted pressing
(
again will
transfer control to the decimal point which may be
positioned between any of the digits, or may be
omitted by moving it to the right of the least
significant digit. When the rate scale factor has
been entered, press
)
to return to the
5CALE . r-A
prompt in the configuration menu.
6.16 Timebase:
‘t-bA5E’
The timebase multiplies the rate display by 1, 60 or
3,600 depending upon whether the Rate Totaliser is
required to display flow rate per second, per minute
or per hour. See Fig 9.
To check or change the timebase, select
t-bA5E
from the configuration menu and press
(
which will
reveal the existing setting. Pressing the
&
or
*
button will scroll through the following three options
to display:
tb-1
for flow / second
tb-60
for flow / minute
tb-3600
for flow / hour
When the required multiplier is displayed press
)
to return to the
t-bA5E
prompt in the configuration
menu.
6.17 Display filter*:
FiLtEr-A
The digital display filter associated with each input
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
as shown below.
First digit Filter time constant
seconds
0X 0
1X 1.3
2X 4.3
3X 6.5
4X 8.7
5X 11.3
6X 15.7
7X 20.9
8X 25.2
9X 31.5
The second digit defines the deviation from the
displayed rate at which the filter will be overridden
and the rate display will move rapidly to the new
value.
Second digit Magnitude of step
change which will
produce a rapid
response
X0 off
X1 1%
X2 2%
X3 4%
X4 8%
X5 12%
X6 16%
X7 24%
X8 32%
X9 64%
By careful adjustment of the two parameters a stable
display with an acceptable input step response can
be obtained for most applications.