Power supply requirements for COMfortel phones
| COMfortel | Basic unit | with 1 Xtension | with 2 Xtensions | with 3 Xtensions |
| 600 (analogue) | Analogue port of the system | |||
| 1200 (ISDN) | S0/UP0 port of the system* | |||
| 1400 (ISDN) | S0/UP0 port of the system* | |||
| 1600 (ISDN) | S0/UP0 port of the system* | |||
| 2600 (ISDN) | S0/UP0 port of the system* | additional power supply unit (COMfortel XT-PS) | ||
| 1200 IP | PoE (IEEE 802.3af, Class 0) | |||
| 1400 IP | PoE (IEEE 802.3af, Class 0) | |||
| 2600 IP | PoE (IEEE 802.3af, Class 0) | |||
| 3200 | PoE (IEEE 802.3af, Class 0) | additional power supply unit (COMfortel XT-PS) | ||
| additional power supply unit (COMfortel XT-PS) | ||||
| 3500 | PoE (IEEE 802.3af, Class 0) | additional power supply unit(COMfortel XT-PS) | ||
| additional power supply unit (COMfortel XT-PS) | ||||
| 3600 IP | PoE (IEEE 802.3af, Class 0) | additional power supply unit (COMfortel XT-PS) | ||
| additional power supply unit (COMfortel XT-PS) | additional power supply unit (COMfortel XT-PS) | |||
*per port max. 2 telephones, for COMpact 3000 max. 1 telephone