Huawei HG8245C

Hello, friend!

When the –48 V power supply is used, the current in the 1200-ohm ring resistance is greater than or equal to 25 mA. When the 1800-ohm ring resistance is used, the current is greater than or equal to 18 mA.

R-Ringing (Ringing)

The ringing function is to provide the ringing current for the phone. The phone rings to notify the user that the call is connected. The ONT is designed based on the balanced ringing feature.

The concept of balanced ringing is relative to the traditional concept of unbalanced ringing. There are two types of traditional unbalanced ringing:

(1) Cable A of the subscriber line is 0 V and cable B is –48 V DC and 75 V RMS AC signals are superimposed.

(2) Cable A of the subscriber line is –48 V, and cable B is 75 Vrms AC signal. Balanced ringing indicates that line A has AC signals and line B also has AC signals. The AC signals of line A and line B have the same frequency and opposite phases, and are differential signals. The frequency of balanced ringing is configurable, including 16 Hz, 25 Hz, and 50 Hz.

In the ONT application environment, the ringing current amplitude of 50 Vrms can meet the requirement. The ringing current amplitude is mainly applied to the short loop (within 1 km). In this case, the power consumption of the port ringing can be reduced.

Thanks!