Electrical Specification; Signal Specification; Figure 3.1 Trunk Line Loop Start Signaling - Samsung OfficeServ 7100 series System Description

3.2 Electrical Specification

3.2.1 Signal Specification

The signal processing protocol means the methods for connecting signals between the trunk
lines, stations and system, and also means the method of providing the status information.
3.2.1.1 Trunk Line Signaling
Loop Start
In processing loop start signals, the on-hook and the off-hook statuses are controlled by the
flow of electric current. The loop is a closed loop trunk circuit or a standard 2500-type set
loop.
T1 Trunk Line: No support
E1 Trunk Line: No support
Characteristics of the ISDN Interface Transmission
The electrical characteristics of the ISDN (PRI) interface comply with the ITU I.431 and
ETS 300 011 standards
© SAMSUNG Electronics Co., Ltd.
OPEN END
GND
T
E
-48 VDC
(C.O.)

Figure 3.1 Trunk Line Loop Start Signaling

OfficeServ 7100 System Description
CLOSED END
T
X
E
Key Telephone
3-3