Dear Friend! hope it can help:
For CS configuration:
Configure the voice service through web pages, U2000, or TR069 servers on an ONT that supports
the voice service. For details, see the user manual of each ONT device.
For Power Range:
For the ONTs using GPON upstream transmission: -27 dBm to -8 dBm (Class B+); -30 dBm to -8dBm
(Class C+).
For the ONTs using XG-PON upstream transmission: -28dBm to –8dBm (Class N1a); -28dBm to -
8dBm (Class N2a).
Thanks!