BEKA BA544D Manual Download Page 13

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display stability. The second digit should then
be increased until the selected step size is
greater than the noise on the display signal, at
which setting the rate display will again
become stable. These will be the optimum
filter parameters for acceptable rate display
stability and a fast response to a large rate
signal change.

To check or change the filter select 'FILtEr'
from the main menu and press

to reveal the

current settings. Pressing the

Down

button will change the flashing digit and

will

transfer control to the second digit. While
making adjustments the filtered rate display is
shown on the lower display so that stability can
be assessed. When set as required, press the

button to enter the revised parameters and

return to the main menu.

5.11 Total scale factor: ‘SCALE-t’

This factor defines the arithmetic relationship
between the number of input pulses and the
total display. SCALE-t is a dividing factor that
may be adjusted between 0.001 and
99999999. See Fig 6.

When used with a flowmeter  SCALE-t should
be set to the K-factor of the flowmeter  i.e. the
number of pulses the flowmeter produces for a
unit of flow.    If the BA544D total display is
required in units different from those in which
the flowmeter K factor is specified, a
conversion factor will be required.

e.g. If the flowmeter has a K factor of 45.6
pulses per litre and the BA544D total display is
required in units of 1,000 gallons, then
SCALE-t should be set to number of pulses
produced by the flowmeter per 1,000 gallons:

45.6 x 4.54609 x 1000

207,301.7 pulses per 1000 gallons

.
(there are 4.54609 litres in a UK gallon)

To check or change the total scale factor select
'SCALE-t' from the main menu and press

reveal the existing setting, one digit will be
flashing. The value of the flashing digit can be
changed by pressing the

Down

buttons.

When this digit is correct pressing

will

transfer control to the next digit.

Note:

After changing the total scale factor, the

total and grand total displays will be reset to
zero.

To position the decimal point in the scale
factor, move the flashing digit to the left hand
side of the required decimal point position and
simultaneously press the

and

Down

buttons.

When the required total scale factor has been
entered, press

E t

o store the number and

return to the main menu.

5.12 Clip-off: ‘CLIP-OFF’

To prevent totalisation of very low flow rates
which over long periods may result in
significant totalisation errors, the BA544D may
be programmed to stop totalising when the flow
rate falls below an adjustable threshold.

To check or change the clip-off threshold select
'CLIP-OFF' from the main menu and press

which will reveal the current setting. The
threshold is shown in units of flow rate with one
digit flashing. The value of the flashing digit
may be changed by pressing the

Down

buttons. When this digit is correct pressing

will transfer control to the next digit. When set
as required, press the

button to enter the

revised figure and return to the main
programme menu.

If the flow rate falls below the entered
threshold, the rate display will show zero flow,
totalisation will stop and the HOLD annunciator
will be activated. The flow indicator will
continue to rotate as defined in section 2.2

Note:

When the rate scale factor SCALE-r, the

timebase t-bASE, or the position of the rate
display decimal point are changed, clip-off will
automatically be reset to zero. If required, a
new clip-off threshold may then be entered.

5.13 Local reset of total display:
‘LOC. rSEt’

When activated this function enables the
operator to reset the BA544D total display to
zero in the display mode by operating the

and

Down

push-buttons simultaneously for two

seconds. To check the status of the local
reset function select 'LOC.rSEt' from the menu
and press

which will reveal if the function is

'On' or 'OFF'. If necessary press the

Down

button to change the setting, followed by

the

button to return to the main menu.