Manual:PoE-Out: Difference between revisions

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==Safety==
==Safety==
This feature on PoE out capable devices have these safety features
This feature on PoE out capable devices have these safety features
====Port eligibility to be powered detection====
auto-on mode is considered safe, it will check if resistance on the port is within range and only then enable PoE out on the interface. The range is 3kΩ to 26.5kΩ


====Overload protection====
====Overload protection====

Revision as of 11:26, 16 February 2012

Summary

this page describes ow poe-out feature can be used on RB750UP and OmniTik UPA. These boards have 100MBps interface and power is provided over the spare pairs.

Configuration

PoE Out feature can be configured for ethernet interfaces as that is an attribute of the ethernet interface that has the feature.

Power on 100MBps interface is provided over spare pairs (blue and brown) where blue pair carries positive and brown - negative.

Each port can be controlled independently.

Configuration options are:

  • auto-on - board will attempt to detect if power can be applied on the port. For power-on to happen there should be resistance on spare pairs in range from 3kΩ to 26.5kΩ. It is the default setting;
  • forced-on - detection range is removed. As a result power over Ethernet will be turned on the port;
  • off - all detection and power is turned off for this port.

How it works

auto-on mode

If auto-on is selected then port operates in this strict order:

  • with low voltage it checks for resistance on the connected port. If it is detected that resistance is in range (3kΩ to 26.5kΩ) power is turned on the interface;
  • when power is given it is continuously checked if overload limit is not reached or short circuit is detected
  • when cable is unplugged port returns in detection state and will remain off until suitable port that could accept PoE is detected

forced-on mode

If forced-on is selected then port operates in this strict order:

  • it is checked if resistance is in range is 0Ω to ∞Ω, so that even if cable is unplugged power will be given on the port
  • when power is given it is continuously checked if overload limit is not reached or short circuit is detected
  • when cable is unplugged port remains with power enabled on the port

Safety

This feature on PoE out capable devices have these safety features

Port eligibility to be powered detection

auto-on mode is considered safe, it will check if resistance on the port is within range and only then enable PoE out on the interface. The range is 3kΩ to 26.5kΩ

Overload protection

when port is on (PoE out is enabled) port is checked for overload, If that is detected to avoid hardware damage of powered device or powering device PoE out is turned of on this port

Short circuit detection

when port is on (PoE out is enabled) port is checked for short circuit. If it is detected to ensure that there is no additional damage on powered device and no damage on powering device PoE out is turned off on all ports

PoE Out polarity

By default PoE out polarity on MikroTik manufactured devices on 100MBps ports is standard

Standard

PoE out on RouterBOARD devices is standard - over blue pair - positive and over brown pair - negative voltage

Reversed

Some devices use different polarity to power their devices that is reverse of the standard: over blue pair - negative and over brown pair - positive voltage

Any

Device that supports either of 2 possible polarities - either standard or reversed

Wiring

If you want to power device that supports only reverse polarity using 'RB750UP and OmniTik UPA you have to make special cable that will swap required wires, thus enabling you to power these devices.

On one end you have to have standard RJ45 T568B wiring (orange striped, orange, green striped, blue, blue striped, green, brown striped, brown) and on other and has to have blue and brown pair swapped resulting in (orange striped, orange, green striped, brown, brown striped, green, blue striped, blue)

RB750UP and OmniTik UPA-5HnD Powered devices

Table contain information on what devices can be powered using RB750UP and OmniTik UPA-5HnD as power source for PoE

Polarity: standard - blue pair positive, brown pair negative; reversed - blue pair negative , brown pair positive, any - either standard or reversed.

Device forced-on auto-on polarity
RouterBOARD RB433GL [1] yes yes any
RouterBOARD RB450G [2] yes yes any
OmniTik UPA-5HnD [3] yes yes standard
OmniTik U-5HnD [4] yes yes standard
RouterBOARD RB711G-5HnD [5] yes yes any
RouterBOARD RB800 [6] no no any
RouterBOARD RB450 [7] yes yes standard
RouterBOARD RB433AH [8] yes yes standard
RouterBOARD RB750 [9] yes yes standard
RouterBOARD RB750UP [10] yes yes standard
RouterBOARD RB435G [11] yes yes any
RouterBOARD RB493AH [12] yes yes standard
RouterBOARD RB493 [13] yes yes standard
RouterBOARD RB532 yes yes standard
RouterBOARD RB153 yes yes standard
RouterBOARD RB112 yes yes standard
Motorolla Canopy yes yes reversed
Ubiquity LOCO900 yes yes standard
Ubiquity Bullet M2 yes yes standard
Ubiquity Bullet M5 yes yes standard
Ubiquity NanoStation 2N yes yes standard
Ubiquity NanoStation M365 yes yes standard
Ubiquity UniFi AP yes yes standard
Ubiquity UniFi AP long range yes yes standard