The terms have the following meanings:
Internally activated: The operator is present. Only the alarm devices allocated to the external device group (group 1) are activated. Internal group devices are not taken into account.
Externally activated: The operator is absent. All devices are activated.
Example: A single-family house is fitted with a Gira alarm control unit. There are motion detectors in the house as well as in the garden and on the approach to the house that are connected to this control unit. The windows also have glass-breakage sensors. Intruders looking to gain access to the house will be detected by the motion detectors in the house when nobody is home. In this case, all the other detectors and sensors (including those outside) should also detect unauthorised access. The alarm control unit should therefore be externally activated when leaving the house. If the family is at home, the motion detectors inside the house do not need to be activated. Unauthorised access to the property grounds should, however, still be detected via the motion detectors and, in the worst-case scenario, by the glass-breakage sensors. Therefore, the control unit should be internally activated here.