It does not have auto detection function and directly supply power to devices by force as as you connect ,powered device or poe splitter must conform to standard IEEE 802.3af/at,the same time your powered device must support poe pin 4/5(and),7/8(-)midspan.Power Input = Power Output x channels,Take 4Port POE,injector as example:DC48V 4A Input = DC12 V1A Output per channel,DC48V 2A Input = DC48V 0.5A output per channel.If you only use 3 of 4 channels,DC12V3 A input = DC12V 1A output per channel.Please select according your device power consumption,in order to stable running,the power consumption must be lower than the power supply.This POE adapter apply for IEEE802.3af/at standard POE powered devices like , and other IP cameras,or being equipped with IEEE802.3af/802.3at standard poe splitter for non POE devices.Led:Indicate the working state,Lan port:8ports in RJ45(data in),8port poe RJ45(dataandpower out),Data in:PC/Hub/Switch/Router,etc.Working temp:0-and40 Celsius.Working humidity:20 -90% RH non-condensing,Storage temp and humidity:-20-and85 Celsius,10-95% RH,weight:120gColour:Black Material:ABS and electronic componentsProduct size:10 x 4.7 x 3.1cmPackage Contents:1 x 4 port POE hub1 x cartonOnly the above package content, other are not included.Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is 1-3cm. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.