I found something. An old modem power adapter. It's 18v 500ma. Just might work.

It turns out that this old power supply that I found is 18v AC. It was fir the zte zxdsl 831 modem. I wonder why it's AC. It also sats 18vac on the modem label.

I got myself an unbranded 19.5v 4.74a laptop charger for php980 from our local electronics shop. It worked now using 30m cable. Thanks to @Victor Ramos and @danymarc for the tip.

Is great... Now you can use without problems the 7210...Regards...

Hi, sorry, I don't understand the amperes part:

I have also this problem and I need a 19v or 20v power supply. But danymarc said:

danymarc wrote

...Make sure amperes are 500mA to 1A..

But Alden uses a 19.5v 4.74a power supply. How important is the amperage?


Thanks and regards

Lukas

Hi, sorry, I don't understand the amperes part:

I have also this problem and I need a 19v or 20v power supply. But danymarc said:

danymarc wrote

...Make sure amperes are 500mA to 1A..

But Alden uses a 19.5v 4.74a power supply. How important is the amperage?


Thanks and regards

Lukas

dear @Lukas-adrian

I refer to minimun curret to device start without problems...

in DC very loss voltage in the cable..in a original power supply 12V / 1A. is teorical for the device in laboratory test... we in house acuse many aditional problems, Temp. Lengh of cable, quality etc...

the current of comsuption is proportional to usage voltage (LAW OHM) more voltage minus current, minus voltage more current...

if power supply original 12V at 1A... and you uses a big power supply example 15 to 20V, no need 1A, need minus current, betwen 0.5A. to more (for te OHM LAW)

in small words, Amperage is Important, if voltaje is down, the device give more curren to compensate the comsuption...

you can uses more current, but no minus...

redards...

PD sorry for my bad english.. is not my native languaje

Some cables are just suck at electrical conductivity, no matter how they are marked as CAT5e or CAT6 for communication SPEC.

The voltage drop on the copper core wires is reason causing the powering issue.

I have been through this experience before. You can test the output voltage at the end of the cable, pin4/5 for DC+, pin7/8 for DC-. If the output voltage is low than 12V, try another adapter of higher voltage.

Check this FAQ.
http://www.tp-link.com/en/faq-906.html

MANY THANKS!
After many weeks, any ethernet cable changes and now with a 19V 3.74A power supply, it works since one week!!!

Regards

Lukas