For some reason when I connect a 5m Ethernet cable to my router it works.
When I connect a 10m Ethernet cable it doesn’t work.
Can I replace my old power supply with another power supply that has more amperage to power my Wi-Fi router?
The amperage rating on your power supply simply means that the supply can put out up to 2 amps, so as long as the voltage matches (12 volts) you could safely use a higher amp power supply for your device.
It never hurts to have a supply that can output more amps than you need, so getting a larger supply could very well be what you need to fix your problem - especially when considering the behavior you described.
I very highly doubt the issue is the power supply. Networking requires very little power and even a cheap, off-brand router is capable of sending a signal 100 meters over copper Ethernet.
More than likely, your 10 meter Ethernet cable is defective.
Additionally, replacing your power supply with one with more amperage is extremely unlikely to make a change. The amount of power needed to send and receive Ethernet signals is extremely low. This is not a problem due to the need for "more amperage."
Yes, sure. If the connector is the same and the voltage is 12V. The ampere value of the new power adapter should be 2A or greater.
Most likely the power supply isn't the problem. If you are using PoE be sure to be using Cat6 or higher cables and preferably solid core ones.
The fact that it works with 5m cable and not with higher means there are losses with the cable you are using.
Even if you would get a higher amperage power supply, it will supply whatever it's requested from the connected device. Just be sure to keep the same voltage.
