Transition Networks
N-GXE-POE-xx-01 User Guide
33599 Rev. E
https:/www.transition.com
Page 13 of 34
Copper
Cable
Requirements
For type 2 loads (25.5W PoE+), Category 5/class D or better cable is required.
Standard
PoE
Parameters
Property
802.3at Type 2
Power available at PD
25.50 W (1).
Max. power delivered by
PSE
30.0 W.
Voltage range (at PSE) 50.0–55.0
V.
Voltage range (at PD)
42.5–55.0 V.
Maximum current
600 mA.
Maximum cable resistance
12.5
Ω
(Category 5).
Power management
Four power class levels negotiated at initial connection or 0.1 W
steps negotiated continuously.
Derating of max. cable
ambient operating temp.
5°C with one mode (two pairs) active.
Supported cabling
Category 5. More stringent cable specification allows assumption of
more current carrying capacity and lower resistance (20.0 Ohms for
Category 3 versus 12.5 Ohms for Category 5).
Supported PoE mode
Mode A.
Notes
:
1. Most switched power supplies within the powered device will lose another 10 to 25% of the available
power.
2. More stringent cable specification allows assumption of more current carrying capacity and lower
resistance (20.0 Ohms for Category 3 versus 12.5 Ohms for Category 5).
Cisco
IP
Phones’
PoE
The following link classifies the Cisco IP Phones with their PoE requirements:
http://www.cisco.com/c/en/us/support/docs/voice-unified-communications/unified-ip-phone-7900-
series/97869-poe-requirement-faq.html
