I want to try my hand at producing a POE battery power supply for use with an access point [AP] for site surveying purposes.
My solution is an 11.1v LiPo 3s pack and charger fro a remote control car rated at 5000mah and a 12V --> 48V step up converter from Ebay, connect the two together and then connect the 48V to a RJ45 Jack and hey presto portable power for the AP.
1) Given a rated power consumption of 200mw what life would I get from the battery? 2) As the POE standard allows for some negotiation on the power supply would simply presenting 48V to the appropriate pins of the Cat5 wirk or do I need some logic in there? 3) Am I likley to hurt my AP with this solution?