2N Lift emergency phone 2N LiftNet - Manual, 1446 v1.8.3 - Manual (Page 16)

Terms and Symbols Used 1.4
16
1.4 Terms and Symbols Used
LN 2N ® LiftNet
CU Central unit of the system, typically shared by multiple lifts in a
building
Audio unit Voice communication unit for lift communication with the
dispatching office or another system unit
System Central unit interconnected with a group of audio units by a bus
Bus A pair of conductors interconnecting the CU and all system audio
units
Incoming call dispatching office-to-CU call
Outgoing call CU-to-dispatching office call
Checking call Automatically activated CU-to-dispatching office call
Triphony Internal communication between audio units, typically all audio units
of one and the same lift, during repairs or rescue work
Dispatching
office Receives emergency calls, checking calls and, if necessary, lift
failure reports. Separate dispatching offices can be responsible for
different types of calls and mobile telephones can be used too.
LM,
LiftManager
Supervisory software designed for small and medium-size lift
supervising companies. Automatic receiving of checking calls.
Comfortable programming of CU parameters.
DISA Automatic voice menu, which helps route incoming calls to the
required audio unit or activate additional functions, e.g. remote
programming
ESS Electronic Security System
PBX Private branch exchange (equipped with PSTN interface and local
analogue lines)
PSTN Public switched telephone network. For simplification, it is assumed
that the CU is connected to the PSTN although it works on the PBX
line too in the same way.