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EXPERT LA
11.2 Alarm Conditions
Temperature Alarms
The diagram below shows how temperature alarms
are detected.
When the average room temperature exceeds the
high temperature alarm setting, a high tempera-
ture alarm is set off. When the average room tem-
perature decreases below the low temperature
alarm setting, a low temperature alarm is set off.
Although these settings are entered by the user as
absolute values, they are defined based on the room
set point. They are thus automatically adjusted if
the set point changes.
The situation is slightly different when the outside
temperature is greater than the room set point. In
this case, the outside temperature becomes the
reference point (instead of using the set point as a
the reference). This means an alarm is set off when
the room temperature reaches Outside Tempera-
ture + High Alarm Offset (the offset being the
difference between the high alarm temperature
setting and the set point). A third parameter, called
the critical temperature, is defined to continue moni-
toring the indoor temperature for high temperatures.
When the indoor temperature reaches the critical
high temperature (defined as an absolute value),
an alarm is set off.
Temperature Alarms
ALARM
LIMITS
HI T° ALARM
High T°
limit
Set point
Low T°
limit
70
EXPERT LA rev.00
Detection of
ROOM TEMPERATURE
Temperature Alarms in Clean Mode
The controller can monitor low temperature alarms
when it is in clean mode. If this alarm condition is
used, the controller sounds an alarm when the tem-
perature falls below low alarm limit that is associ-
ated to the clean mode.
The low alarm limit used in clean mode is related
to the clean mode set point; this means the alarm
limit is automatically adjusted when the clean mode
set point changes.
Water Spill Alarm
A water spill alarm is set off when the water con-
sumption exceeds a user-defined limit. This limit can
be adjusted from 0 to 10,000 gallons or liters per
15 minutes. The alarm is activated if a greater amount
of water is consumed within the 15 minute delay.
Static Pressure Alarms
The controller can sound an alarm when the static
pressure (SP) level exceeds high or low pressure limits
for a certain period of time. Note that the low static
pressure alarm is not used in natural ventilation.
Feeder Alarm
The controller sets off an alarm if a feeder runs
continuously on a too long period of time. When
this type of alarm occurs, the relay associated with
the problematic feeder opens in order to stop the
feeder motor. This alarm condition is optional.
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