To check or change the alarm output status select
'no.nc' from the alarm sub-menu and press
P
to
reveal the current setting. The function may be
changed by pressing the
Up
or
Down
buttons
followed by the
E
button to return the 'no.nc'
prompt.
11.3.5 Hysteresis: HStr
To adjust the alarm hysteresis select 'HStr' from
the alarm sub-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 the 'HStr'
prompt.
e.g. A transmitter with a high alarm set at 240 and
hysteresis of 10 will perform as follows:
High alarm will be activated when display
equals or exceeds 240, but will not reset until
the display falls below 230.
11.3.6 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
sub-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 the
'dELA' prompt.
11.3.7 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 sub-menu and press
P
which will reveal
the existing time. Each digit may 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 the 'SIL'
prompt.
11.3.8 Access Setpoint: AcSP
This function controls the parameters in a separate
menu which provides direct access to the alarm
setpoints when the transmitter is in the display
mode i.e. when it is displaying temperature. See
section 11.4 for a full description. This menu
allows an operator to adjust the two alarm
setpoints without having access to the Programme,
Trim or Alarm Menus. A separate security code
may be defined to prevent unauthorised access.
This separate direct access menu is enabled and a
separate security code entered from the 'AcSP'
function in the Programme Menu - see Fig 13. To
change the menu parameters select 'AcSP' from
the Programme Menu and press
P
which will
display the enable prompt 'EnbL'. Press
P
again to
reveal if the direct access menu is 'On' or 'OFF'.
The
Up
or
Down
buttons will toggle the display
between the two conditions.
If 'OFF' is selected, the operator will not have
access to the setpoints from the display mode.
Return to the 'AcSP' prompt in the main menu by
pressing
E
twice.
If 'On' is selected, the operator will have direct
access to the alarm setpoints from the display
mode via a separate optional security code. To
define the four digit numerical code press
P
to
return to the 'Enbl' prompt followed by the
Up
or
Down
button to select the access code prompt
'AcCd'. Pressing
P
will reveal the current security
code. Each digit of the code may be changed by
operating the
Up
and
Down
push-buttons, and the
P
button to move to the next digit. When the
required code has been entered, press
E
twice to
return to the 'AcSP' prompt in the Programme
Menu.
Code 0000 will disable the security code allowing
direct access to the setpoints by pressing the
P
and
Up
buttons simultaneously.
New instruments are supplied with this function
disabled and the security code set to 0000
26