44
The curve represents
the
Measured
Temperature
1:
Detection of measured temperature alarm greater than Tsup
2:
Send SMS alarm message (status: higher temperature alarm)
3:
Reset alarm; the device can now detect a new higher temperature al
arm�
Tsup - DTA
Tsup + 0,1°C
Tsup
1
3
2
13.6.2 Alarm for temperature exceeding the upper temperature threshold value
The GSM chronothermostat can send an SMS alarm message if the temperature exceeds the
threshold set by the user; this alarm condition is detected when the measured temperature is greater than
the set upper threshold value (indicated by
Tsup
) by at least 0�1°C�
After sending the alarm SMS message to the telephone numbers previously set, the chronothermostat
remains in the state of “alarm sent” and, as long as it remains in this state, it will not send any more
higher temperature alarm messages; this condition persists until the measured temperature falls under
the value of:
Tsup - DTA
where
DTA
is the temperature differential defined for managing the temperature alarms and its value
is the same for managing both the higher and lower temperature alarm�
The following figure outlines what has just been described:
For managing the higher temperature alarm, it is necessary to carry out the following configuration
procedures:
• Setting the value of the upper temperature threshold�
• Enabling the alarm�
• Associating the alarm with the telephone numbers to which the SMS message must be sent�
• Changing the value of the temperature differential DTA (optional)�
• Customizing the Address Msg� (optional)�
Note
: The DTA has a predefined value that is already set and is optimal for most installation
applications; if you change it, bear in mind that, if there are considerable variations in temperature
around the set threshold value, too low a value assigned to the DTA could cause numerous SMS
alarm messages to be sent out�
