BEKA BA314E, Manual

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The second digit defines the deviation from the
displayed speed at which the filtering defined by the
first digit will be overridden and the Tachometer speed
display will move rapidly to the new value.
Second
digit
Magnitude of input
step change which
will override the filter
and move the speed
display rapidly to the
new value..
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.
During commissioning it is recommended that initially
the second digit is set to 0 (off) and the first digit is
adjusted to provide an acceptable Tachometer display
stability. The second digit should then be increased
until the selected step size is greater than the noise
on the display, at which setting the Tachometer speed
display will become stable. These will be the optimum
filter parameters for acceptable Tachometer speed
display stability and a fast response to a large speed
change of the monitored machinery.
To check or change the filter select
FiLtEr
in the
configuration menu and press
(
which will reveal the
current settings with the first digit flashing. Pressing
the
& or *
button will change the flashing digit and
(
will transfer control to the second digit. While
making adjustments the filtered Tachometer display is
shown on the lower display in place of run-time so that
stability can be assessed while adjustments are being
made. When set as required, press the
)
button to
enter the revised parameters and return to the
FiLtEr
prompt in the configuration menu.
6.13 Clip-off:
CLP oFF
Clip-off determines the displayed speed at which the
run-time counter starts to function, below this
threshold the run-time counter does not function. If
the run-time counter is required to operate whenever
the Tachometer is powered, clip-off should be set to
zero.
If the run-time display is not being used it is not
necessary to enter a clip-off value - see 6.8.
To check or change the clip-off threshold select
CLP oFF
from the configuration menu and press
(
which will reveal the current setting. The
threshold is shown in the units already selected for
the Tachometer speed display with one digit flashing.
The value of the flashing digit may be adjusted by
pressing the
&
or
*
button, when set as required
pressing
(
will transfer control to the next digit.
When all the digits have been adjusted, press the
)
button to enter the revised threshold and return
to the
CLP oFF
prompt in the configuration menu.
When the Tachometer speed display falls below the
clip-off threshold, the HOLD annunciator will be
activated and the run-time clock will be stopped.
Note:
To avoid confusion, when the speed scale
factor
5CALE . 5
, timebase
t-bA5E
, or the
position of the speed display decimal point
dp
are changed, clip-off will automatically be
reset to zero. A new clip-off threshold must be
entered after any of these changes have been
made.
6.14 Local reset:
LoC clr
The Local reset function contains two sub-functions
clr tot
and
clr gtot
which when enabled allow the
run-time display and grand total run-time to be reset
to zero via the instrument push buttons while the
Tachometer is in the display mode.
6.15 Local run-time reset:
clr tot
clr tot
is a sub-menu in the LoC
clr
function
which when activated allows an operator to reset the
run-time display to zero while the Tachometer is in
the display mode by operating the
&
&
*
push
buttons simultaneously for more than three seconds.
Select
LoC clr
in the configuration menu and press
(
which will reveal the
clr tot
prompt, operate
(
again which will show if the local run-time reset is
on
or
oFF
. If set as required operate the
)
button
twice to return to the configuration menu, or the
&
or
*
button to change the setting followed by the
)
button twice to enter the change and return to
the
LoC clr
prompt in the configuration menu.
Note:
The run-time display may also be reset to zero
remotely by connecting terminals RS1 and
RS2 together for more than one second. See
sections 3.5; 4.1.8 and 4.2.8 of this manual.
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