BEKA BA334NG, Manual

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10.3.8 Alarm output status:
no . nC
Each single pole alarm output may be open or
closed in the non-alarm condition. When the
BA334NG power supply is turned off or
disconnected, the alarm output(s) will open
irrespective of whether normally open or normally
closed outputs have been selected. Therefore when
designing an alarm system normally closed nc
should be selected so that the output opens when
an alarm occurs or if the power supply fails.
Using the
&
or
*
push button select
no,nC
from
the selected alarm sub-menu and press
(
to check
or change the function. The
&
or
*
push button
will toggle the contact status between
no
and
nC
,
when set as required, press the
)
button to return
to the
no,nC
prompt in the alarm sub-menu.
10.3.9 Hysteresis:
H5tr
Hysteresis is only available on rate alarms so the
H5tr
function only appears in the configuration sub-
menu when alarm
tYPE
has been set to
rAtE
.
During configuration hysteresis is shown in the units
of rate previously configured for the rate display.
Using the
&
or
*
push button select
H5tr
in the
selected alarm sub-menu and press
(
which will
reveal the existing hysteresis with one digit flashing.
The required hysteresis can be entered using the
&
or
*
push button to adjust the flashing digit and
the
(
button to transfer control to the next digit.
When set as required press
)
to enter the value
and return to the
H5tr
prompt in the alarm sub-
menu.
e.g. A Rate Totaliser configured to display a flow of
0 to 5000, with a high alarm set at 4000 and
hysteresis of 100 will perform as follows:
High alarm will be activated when flow
equals or exceeds 4000, but will not reset until
the flow falls below 3900.
10.3.10 Alarm delay:
dELA
This function enables
activation of the alarm output to be delayed for a
fixed time following the alarm condition occurring.
The delay can be set in 1 second increments up to
3600 seconds. If a delay is not required zero
should be entered. To adjust the delay select
dELA
using the
&
or
*
push button in the selected
alarm sub-menu and press
(
which will reveal the
existing delay time in seconds with one digit
flashing. The required delay time can be entered
using the
& or *
push button to adjust the
flashing digit and the
(
button to transfer control
to the next digit. When set as required press
)
to enter the value and return to the
dELA
prompt in
the alarm sub-menu.The Rate Totaliser's alarm
annunciator will start flashing immediately an alarm
condition occurs and will continue for the delay
time, after which the alarm output will be activated
and the alarm annunciator will be permanently
activated.
10.3.11 Alarm silence time:
5IL
The alarm silence function is primarily intended for
use in small installations where the alarm output
directly operates an annunciator such as a
sounder. When the alarm silence time is set to any
figure other than zero, the
(
push button
becomes an alarm accept button.
After an alarm has occurred, operating the
(
button will cause the alarm output to revert to
the non-alarm condition for the programmed alarm
silence time. When an alarm is silenced by
operating the
(
push button, the Rate Totaliser's
alarm annunciator will flash until the silence time
expires.
To adjust the alarm silence time select
5iL
using
the
&
or
*
push button in the selected alarm
sub-menu and press
(
which will reveal the
existing alarm silence time in seconds with one
digit flashing. The required silence time can be
entered using the
&
or
*
push button to adjust
the flashing digit and the
(
button to transfer
control to the next digit. When set as required
press
)
to enter the value and return to the
5iL
prompt in the alarm sub-menu.