PureAire Monitoring Systems, Inc.
33
5.5.9 Set Alarm Hysteresis
(Only available on O
2
monitor with Relays)
PureAire’s oxygen monitor may be used as a control system. When used to regulate
oxygen levels the need of a dead band, “hysteresis” may be required for the alarm
relays. This menu will permit the setting of the alarm hysteresis to a desired
concentration of Oxygen. When using hysteresis, the alarm set point now becomes an
average alarm setting for an action to occur. When adding the hysteresis value to the
alarm set point, this then defines the alarm and dead band for an action to occur.
For example, if you require a valve to close at 14.9% oxygen level and to reopen again
at 15.5% oxygen level, you will set the Alarm Threshold at 15.2% and set the hystersis
value at 0.3%.
Average Alarm set point = 15.2% - Hysteresis 0.3% = 14.9%, Valve Off
Average Alarm set point = 15.2% + Hysteresis 0.3% = 15.5%, Valve On
To access this menu, push the joystick down to display the
Set Alarm Hysteresis
menu. This will scroll on the digital display.
Push the joystick right to access the
Set Alarm 1 Hysteresis
. Pushing the joystick again
to the right will display a value 0.0%, (factory default). Pushing the joystick up
increases the percentage up to a maximum value of 2.5%. Adjust the digital display
until the desired hysteresis value is selected.
Press
ENTER
to accept this value. The digital display will revert to
Set Alarm 1
Hysteresis.
Push the joystick down to access the next sub menu;
Set Alarm 2 Hysteresis
will scroll
on the digital display. Pushing the joystick again to the right will display a value 0.0%.
Pushing the joystick up increases the percentage up to a maximum value of 2.5%.
Adjust the digital display until the desired hysteresis value is selected.
..Set Alarm Hysteresis…
20.9%
0.3%
20.9%
..Set Alarm 1 Hysteresis…
20.9%
..Set Alarm 2 Hysteresis…
20.9%
NOTE:
The
menus
highlighted in
light gray are
only used for
O2 monitors
with the Alarm
Relay Board
They are
displayed on
the O
2
monitor
and their
function is
disabled.
