Battery powered TP-Link TL-MR3020 routers

I’m currently working for a personal project on battery powered wireless LAN devices which in the end should be able to automatically connect to each other within a wireless network mesh. I’m using three TP-Link TL-MR3020 routers for my experiments. They are small devices with a size of 74 x 67 x 22 mm and a weight of 58 g.

The first step was finding an adequate battery-packs as power supplies. I used four Mignon (AA) batteries in a battery-pack, connected in series, and added a self-built mini-USB connector to it. The battery packs add some extra weight: a router plus battery-pack together weights 186 g.

Battery Powered TP-Link Router

It looks like these TP-Link 3020 routers can last quite some time powered by these batteries. The routers are slightly oversupplied by the 5.6 Volts (when fully charged) from the eneloop batteries, but I have not yet recognized any instabilities. I measured the power consumption between of a router at its peak, under load (wireless traffic) and in idle state (with wifi turned on).

System State Power Consumption (ca.)
idle (wifi on, but no traffic) 71 mA
normal load 112 mA
peak (wifi + ethernet traffic) 166 mA

WTF? Phosphorescent power supply

I’m not sure what to make of this: last evening I played around with a new hardware device (a TP-Link TL-MR3020 router, but that’s not the point). I was leaving the room and just as I turned off the lights I noticed a green spot on my desk. The USB power supply of the device emitted a green phosphorescent glow (Wikipedia).

Phosphorescent power supply (under normal lighting)
Phosphorescent power supply (ISO 100; 30 seconds exposure)

I’m not sure why the manufacturer used a phosphorescent material for the case of the power supply, but the effect is quite impressive (creepy) and lasts for some minutes. By the way, it’s a Huntkey Switching Power Adapter model HKA00605010-3B.