YSI IQ SensorNet 2020 XT Terminal - Manual (Page 148)

Settings/setup System 2020 XT USB
5 - 28 ba76019e01 12/2012
5.10 Alarm settings
5.10.1 General information
Under this menu item you can specify reactions on certain alarm
events.
An alarm event is when a certain measured value (limiting value) of a
sensor is exceeded or undercut. You can configure up to 20 alarm
events.
Alarm events can be relayed as follows:
 as a message on the display
 as a relay action (with corresponding output module)
 as SMS (with ready-to-operate GSM modem)
Note
An alarm message via display or relay cannot be acknowledged or
switched off. An alarm only disappears if the cause for the alarm was
eliminated or the Alarm settings were changed or erased. An SMS
alarm message is only sent once when an alarm event occurs.