They can all use for home and SOHO users, indoor optical network terminal (ONT)
HG8240 Ports: 2POTS + 4GE
HG8245 Ports: 2POTS + 4GE + 1USB + 1Wi-Fi
HG8247 Ports: 2POTS + 4GE + 1USB + 1CATV + 1Wi-Fi
2 As the ports shown in above, the HG8240 no WI-FI and IPTV function, just works as a light cat.
3 HG8245 and HG8247 with the wireless WIFI and IPTV function, can connect to the spare battery unit and USB storage devices.
4 HG8247 has the CATV coaxial cable port, can directly connect to TV, while the HG8245 can only use the cable connection to achieve this function.
More related for the HG8247, please visit:What is the feature of Hauwei Echolife HG8245