Virtual sensor "SNMP Get"  is used to read data from external equipment via SNMP PDU GET.

For example, get value from the internal voltage sensor on another master-module.
The internal voltage SNMP OID is the .1.3.6.1.4.1.39052.1.3.1.9.203001 , where 203001 is the ID of this sensor,  9 is the value row number and .1.3.6.1.4.1.39052.1.3 is the sensors table. See more Monitoring system elements overview in the SNMP manual

For other settings descriptions, see "SNMP Get".

SNMP connection settings:

For alarm notification, define the logic scheme for critical voltage events:

The notifications "Email" and "SMS" must be created before adding a new logic scheme, as described in Creating notifications