Data Sheet

12/23/2015 PowerOverEthernetforArduino|Freetronics
http://www.freetronics.com.au/pages/poweroverethernetforarduino#.VnqWJrZ97IU 3/6
Stripbackabout5mmofinsulationfromtheendofeachcable,thentwistthepairofpositivewirestogetherandthepairof
negativewirestogether.Thenuseasolderingironto"tin"eachpairsotheyarereadytoconnecttoapowerjack.
Soldereachpairtotheappropriatepinsonapowerjack.It'sprobablymostconvenienttousea2.1mmDCjacksincethat's
thesameasthepowerconnectorontheArduino,andyou'llbeabletopluginthesamepowerpackasyouwouldusewith
theArduinodirectly.Don'tforgettoprefitthejacksleeveoverthewire,becauseyoucan'tgetitonlateronceyou've
solderediton!
ScrewthejacksleeveontothebackoftheDCjackandyou'rereadytogo.Plugthecablebackintoyourswitchand
connectadeviceattheotherendtomakesuretheLANconnectionstillworksafteryourmodifications.
Ifyouconnectapowersupplytothatpowerjackyouwillnowhavepoweravailableonthatnetworksegment.
ModifyinganEthernetcableisagoodwaytogoifyouwanttokeepeverythingascheapaspossible,butaneatersolution
istouseamidspaninjector.Thiswillallowyoutoconnecteverythingupwithoutdoinganysoldering,doesn'trequire
modifyingthecable,addssomepowersupplysmoothing,andallowsyoutouseasinglepowerpackwithmultiplenetwork
segments.
ForcheapPoEwithanArduinoit'snotnecessarytouseamidspaninjector
thatsupportsthefull802.3standard.Asimpleinjectorthatperformsthesame
jobasthehandsplicedcabledescribedaboveisallyouneed.Freetronics
haveasimple4channelPoEMidspanInjectorthatworksjustfinewithan
Arduino:simplyconnectthe"switch"sidetoyourEthernetswitchwithshort
patchcables,plugyourregularLANcablesintothe"device"side,andconnect
anappropriatepowersupplytothe2.1mmDCpowerjack.The4channel
injectorincludesasmoothingcapacitortohelpremoveanyvoltagevariationin
thepowersupplyanda"bridgerectifier"thattakeseitherDCinputpolarity(or