BEKA BA524D, Manual

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8.2.5 Alarm function: HI.LO
Each alarm can be conditioned as a high or low
alarm. To check or change the alarm function
select 'HI.LO' from the alarm menu and press
P to
reveal the current setting. The function can be
changed by pressing the
Up or Down buttons
followed by the E button to return to the alarm
menu.
8.2.6 Alarm output status: no.nc
This function allows the alarm output to be open or
closed in the alarm condition. When deciding
which is required, care must be taken to ensure
that the alarm output is fail safe. See Fig 8.
CAUTION
When the 4/20mA supply is removed
both alarm outputs will open
irrespective of conditioning.
Therefore for fail safe operation both
alarm outputs should be
programmed to be open in the alarm
condition.
To check or change the alarm output status select
'no.nc' from the alarm menu and press
P reveal the
current setting. The function can be changed by
pressing the
Up or Down button followed by the E
button to return to the alarm menu.
8.2.7 Hysteresis: HStr
During programming hysteresis is shown in the
units the indicator has been calibrated to display.
To adjust the hysteresis, select 'HStr' from the
alarm menu and press
P which will reveal the
existing figure. Each digit can be adjusted using
the
Up and Down push-buttons, and the P button to
move to the next digit. When the required
hysteresis has been entered, press
E to return to
the alarm menu.
e.g. An indicator calibrated to display 0 to 10000,
with a high alarm set at 9000 and hysteresis of 200
will perform as follows:
High alarm will be activated when display
equals or exceeds 9000, but will not reset
until the display falls below 8800.
8.2.8 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
programmed in 1 second increments up to 3600
seconds. If a delay is not required zero should be
entered. To adjust the delay select 'dELA' from the
alarm menu and press
P which will reveal the
existing delay. Each digit of the delay can be
adjusted using the
Up and Down push-buttons, and
the P button to move to the next digit. When the
required delay has been entered, press E to return
to the alarm menu.
8.2.9 Alarm silence time: SIL
This 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
P push-button becomes an alarm
accept button. After an alarm has occurred,
operating the
P button will cause the alarm output
to revert to the non-alarm condition for the
programmed alarm silence time. The display will
continue to indicate an alarm after it has been
accepted and silenced. The alarm silence time
may be adjusted between 0 and 3600 seconds in 1
second increments.
To adjust the alarm silence time select 'SIL' from
the alarm menu and press
P which will reveal the
existing time. Each digit can be adjusted using the
Up and Down push-buttons, and the P button to
move to the next digit. When the required time
has been entered press
E to return to the alarm
menu.
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