Nano needs 24V 500mA and cpe210 draws 1A. Power supply can not give 1,5A. I had similar problem with 5210 when I tried to power another device same time. Any net activity and devices restarted. I found 12V 5A power supply and everything had been working great for 5 years.Find 24V min 2A and power injector (I have a few spare, but it is complicated to send it so far) or make one (two rj45 female connector and one dc socket).




Original PS is on right side and custom one is on left side.

Also be sure that you use good quality 70m cat shilded cable. For me better results I got with wall cable.

@srmarkovic

Great experiment which leads to the true!

@deecypher

I am powering the PoE using the supplied PoE injector with the CPE210 and running it about 70 meters CAT5e.

The permitted length given by TP-LINK is 60 meter, personally I can achieve 90 meter for light load application for one AP. Now that you are using PoE passthrough to power another AP, the effective length will decrease as the voltage drops on the UTP wire. The two AP couldn't get enough power from the original adapter at such a long distance.

As @srmarkovic introduced, using a adapter of higher power/higher voltage can be helpful for this case.