Ethernet over Power Adapter causing modem to disconnect

[Powderedhippo]

HI All, I recently purchased a TP-Link TL-PA9020P KIT AV2000 Ethernet over Power kit and followed the setup instructions to the letter.

When I connect the adapter to a LAN port on the modem via network cable (for network connection as instructed) it causes my modem to lose it's connection to the internet. When I disconnect the network cable connecting the adapter to the modem, the connection returns.

I have no idea what the issue could be and hopefully someone can assist.

To help, I live in Sydney, Australia and have a Cable internet connection (modem connects to internet with a coaxial cable).

 

[Ralston18]

Your setup being something similar to the following line diagram:

ISP ----coax-------> modem/router [LAN port]-------ethernet cable ------>powerline adapter =====electrical circuit =====>the other powerline adapter [LAN port] -----ethernet cable------->computer.

Please correct the diagram as necessary. Make and model modem/router will be helpful information.

Do you have the Power Adapter's User Guide?

If not:

http://www.tplink.com/res/down/doc/TL-PA9020P_KIT_V1_UG.pdf

Check the LED indicators.

Work through the troubleshooting appendix. See if you can narrow down the problem.

First try another known working ethernet cable(s).

 

[Mister_MO]

Do you use shielded ethernet cable? It could be bad grounding on your modem power adapter that cause this.

 

[Powderedhippo]

Diagram is correct and I've worked through the troubleshooting but it mainly troubleshoots the adapters and not the internet connection. The adapters create a network between themselves without any problems, all the LEDs are OK. It's when I plug the adapter into the modem that the modem loses its connection to the internet.

Fairly certain the ethernet cables are shielded. I'll try another one though and see if that works.

 

[Mister_MO]

What i mean is that shielding can cause this problem, as most routers don't have grounded power supply and power line adapters are most of time grounded, so you could ground something in router that isn't supposed to be grounded through cable shielding.

 

[bill001g]

What i mean is that shielding can cause this problem, as most routers don't have grounded power supply and power line adapters are most of time grounded, so you could ground something in router that isn't supposed to be grounded through cable shielding.

This is the exact reason that ethernet ports are magnetically isolated. Any common ground between 2 pieces of equipment can cause a ground loop issue. This is mostly a safety issue but it can damage equipment.

Still it likely does not apply. Almost no equipment has the ability to ground the shielded cable. There are special metal tabs in the equipment that then must connect to the metal shell of a shielded ethernet cable. This special equipment also has a different ground connection on the chassis to connect a different ground than the electrical ground to. It is not the same as the electrical ground, it is kept separate again for safety reasons.

Shielded cable has little use other than in very specialized areas like manufacturing where there is a lot of interference. In these cases the shielded cable is run between patch panels that have special grounds, normal cable is then connected to the equipment since the equipment has no way to ground the shielding even if it wanted to.

Because of use of magnetic isolation and the extremely low voltage and current plugging a device into another one will not cause a issue because of power.

This is more likely a issue with mac or ip address conflict.

 

[The Paladin]

I suggest trying this

~~~ISP~~~CABLE MODEM/=/ROUTER----SWITCH---POWER LINE ADAPTOR [=====]POWER LINE ADAPTOR --- COMPUTER

get a 4 port switch and put it between the router and power line adaptor, also make sure your power line adaptor are not on power bar, power strip or multiple plug blocks on a wall it must be connected to an unfiltered power source.