service Access Platform MSAP2000 User guide

11. System Parameter Specification
MSAP2000 Technical Manual V3.0 11-9
11.6. Pay Phones
Parameters FXO-P (COT) FXS-P (RT)
Subscriber Phone
Signaling format
DP and DTMF
Signaling Transmission
Format
Channel Associated Signaling (CAS) or
Common Channel Signaling (CCS)
Caller ID Display (See
“Note” below)
DTMF and FSK
Impedance (balanced) 900Ω 600Ω
Line Code ITU-T G.711 A-law
Polarity Reversal Polarity Guard Polarity Reversal
Detection
Minimum startup
voltage required for RT
≥20mA. The DC
loop resistance is
1200Ω (including
internal phone
resistance)
Charging Signal (Figure
11-G)
16KHz±160Hz
(12KHz±120Hz)
16KHz±160Hz
(12KHz±120Hz)
Detection 3~5Vrms
Charging Pulse 1V~3V
Standard
specification
(Table 11-C)
DC Voltage -44V~-56V