RTC Series
RTC Installation Guide
01A.04
20
APPENDIX (C): POWER OVER
ETHERNET
The Power over Ethernet (PoE) is designed to extract power from a conventional
twisted pair Category 5 Ethernet cable, conforming to the IEEE 802.3af Power-
over-Ethernet (PoE) standard.
IEEE 802.3af allows for two power options for Category 5 cables.
The IEEE 802.3af-2003 standard allows up to 15.4 W power to device.
However, 12.95W is the maximum available power, as some power gets lost in
the cable.
PoE has advantages over conventional power in such places where AC powers
cannot be reached or expensive to wire.
Note: For proper activation of 12V PoE, the Category 5 cable must be shorter
than 140m and conform the PoE standard.
PoE compatibility
With non-Power Sourcing Equipment (PSE)
When it is connected with non-PSE, the power adaptor should be used.
With power adaptor
Connecting both PSE and power adaptor do not cause any harms to the
products. Disconnecting power adaptor while it is operating does not stop
operation. The product continues to work without rebooting.
Power classification
The PoE Power Class supported by the IP device is Class 0.
Class
Usage
Minimum Power Levels
Output at the PSE
Maximum Power Levels
at the Powered Device
0
Default
15.4W
0.44 to 12.95W