Eelectrical Standard; Figure 1.2 Loop Start C.o. Line Signaling; Table 1.7 Electric Characteristics Of T1 C.o. Line - Samsung OFFICESERV 7100 Service Manual

1.3.2 Eelectrical Standard

The signal processing protocol indicates the method to connect signal between the C.O./extension
line and the system and to provide the status information.
Loop Start C.O. line Signaling
The on-hook and off-hook status is controlled by the electric current flow in the loop start
signal processing. Loop indicates the closed loop C.O. circuit or standard 2500 type set loop.
T1 C.O. line Signaling
The electric characteristics of Ti C.O. line observes ITU G.703 and G.704 standards.
Category
Transfer Rate
Code
Pulse Type
Signal Standard, Signaling method
Transfer Media
Load Resistance
Display(Pulse) Nominal Peak Voltage
© SAMSUNG Electronics Co., Ltd.
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GND
T
E
-48 VDC
(C.O.)

Figure 1.2 Loop Start C.O. line Signaling

Table 1.7 Electric Characteristics of T1 C.O. line

1544 kbit/s ± 50 ppm
Alternative Marking Inversion(AMI) or B8ZS
The mask feature satisfies ITU G.703.
ITU G.703 and G.704 standards are satisfied.
Twisted-pair line
100 Ω
3.00 V
OfficeServ 7100 Service Manual
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T
X
E
Key Telephone
Description
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