BEKA BA538C, Manual

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8.3.5 Setpoint adjustment: ‘SPx1’ and
‘SPx2’
The rate alarm setpoints SPr1 and SPr2 may be
positioned anywhere between 0 and 999999, and
the total alarm setpoint SPt1 and SPt2 anywhere
between 00000000 and 99999999.
To adjust the setpoint of alarm 1 select 'SPr1' or
‘SPt1’, depending upon how it has been
programmed, from the alarm menu. Press
P which
will reveal the existing value with one digit
flashing. Each digit of the setpoint can be
adjusted using the
Up and Down push-buttons,
and the P button to move to the next digit. The
position of the decimal point is defined by the d.P.
function which should be set first. When the
required value has been entered press
E to return
to the alarm menu.
Note: ‘SPr1’ is displayed when alarm 1 has been
programmed as a rate alarm and ‘SPt1’ when
programmed as a total alarm.
8.3.6 Alarm function: ‘HI.LO’
Each alarm must 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.
8.3.7 Alarm output status: ‘no.nc’
The two alarm outputs may be open or closed in
the non-alarm condition. When the BA538C
power supply is turned off or disconnected, both
the alarm outputs 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.
To check the alarm output status select 'no.nc'
from the alarm menu and press
P to 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.
8.3.8 Hysteresis: ‘HStr’
Hysteresis is only available on rate alarms.
During programming hysteresis is shown in the
units of rate the BA538C 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. A BA538C calibrated 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.
8.3.9 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 time. 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.
The alarm annunciator will start flashing
immediately an alarm occurs and continue for the
delay time after which the alarm output will be
activated.
8.3.10 Alarm silence time: ‘SIL’
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
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. When an alarm is silenced the alarm
annunciator will flash until the silence time
expires.
To adjust the silence time select 'SIL' from the
alarm menu and press
P which will reveal the
existing time. The time may be adjusted to
between 0 and 3600 seconds in 1 second
increments. Each digit can be adjusted using the
Up and Down push-buttons, and the P button
transfers control to the next digit. When the
required time has been entered press
E to return
to the alarm menu.