20
9.3.4 Alarm enable: EnbL
This function allows the alarm to be enabled or
disabled without altering any of the alarm
parameters. To check or change the function
select 'EnbL' from the alarm menu and press P
which will 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.
9.3.5 Setpoint adjustment: SP1 and SP2
The setpoint of each alarm may be positioned
anywhere between -19999 and 19999 providing
this corresponds to an input current between 3.8
and 20.2mA. e.g. If the indicator has been
calibrated to display 0 with 4mA input and 10000
with 20mA input, the two alarm setpoints may be
positioned anywhere between -125 and 10125.
To adjust the setpoint select 'SP1' or 'SP2' from
the alarm menu and press P which will reveal the
existing alarm setpoint. 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.
When the required setpoint has been entered
press E to return to the alarm menu.
9.3.6 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.
9.3.7 Alarm output status: no.nc
This function allows the alarm output to be open or
to be closed in the non-alarm condition. When
deciding which is required, care must be taken to
ensure that the alarm output is fail safe. See Fig 8.
‘no’ Alarm output open in non-alarm condition
‘nc’ Alarm output closed in non-alarm condition
WARNING
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.
9.3.8 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
hystersis 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.
9.3.9 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. 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.
9.3.10 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.
