LAN Socket on a power adaptor?

I've got a 10 way power adaptor that also has a lan socket on it. What would that be for? It's not a powerline kit, just a splitter.

Normally it's an in out surge protector, what does the packaging say?

Photo?

On closer inspection its a phone socket rather than lan and seems to be surge protection as you say..

It’s surge protection for your phone line.
You route the incoming line through that, and it’s supposed to save you’d from voltage spikes that arrive from the phone line.

Do you need to surge protect your phone line? Time to do some reading.
https://www.google.co.uk/amp/s/www....ter-tips/do-surge-protectors-really-work/amp/

I hope this is a joint in a speaker cable:

Right.. no need of that then as not had a landline for best part of a decade.

And yes that is a speaker connection not 240v

kaseryn said:

Right.. no need of that then as not had a landline for best part of a decade.

Click to expand...

A foolish idea, IMO.

Taylortwocities said:

Do you need to surge protect your phone line? Time to do some reading.
https:www.online-tech-tips.com/computer-tips/do-surge-protectors-really-work/amp/

Click to expand...

URL fixed to remove the Google redirect ...
Hmm, there's "a few things" wrong in that article - and it never mentions differential vs common mode at all.
One important point is that a lightning rod is NOT there to conduct strikes - that's only a secondary function. It's main function is to discharge the energy before it builds up enough to create a strike. That's why they are always pointed - the point creates a concentration of the electrical field, and in the presence of building charge in the thunderstorm a corona discharge will develop around the point, drawing charge in and taking it to ground.
If you do have a direct strike, don't depend on the lightning conductor to save the building or anything in it. Many years ago when Wireless World was morphing into Electronics World, I recall reading an article in it where someone had gone to a church in the alps to deal with the failures caused by a direct strike.
The conductor itself was blown apart wherever it had a bend, as was the internal power cabling which as well as being blown apart at bends, was generally "melted". Most electronic equipment was toast, but the author noted that the equipment that did survive had an inefficient shunt-regulator power supply.

He does mention whole house protection, and these are a good idea. BUT you also need to route ALL services via the same point and protect them all using the same earthing. Why ?
Well a couple of jobs ago, a not uncommon task was going to the MDs house to replace something or other. They lived a little bit "out in the sticks" with long overhead cables for both power and phone (for good measure, coming from different directions). The result was that when there was a thunderstorm, they got induced voltages in either mains or phone - so a large differential voltage between mains and phone. Ordinary phones were not affected, things only connected to the mains were OK, but anything mains powered and connected to the phone line (fax, modem, answering machine) would tend to get fried.
So the answer is that whole house really means that EVERYTHING needs to come in via the same point and have surge protection to the same earth. That way, even if the earth isn't too good*, then the differential between services (typically between phone and mains) will be restricted.
* bear in mind that the rate of rise of current in a lightning strike is such that even a few feet of 10mm² cable will have enough inductance as to make it of limited value in earthing surge protectors I've also seen a demonstration (when starting as an apprentice) of how a very expensive interference filter was rendered useless by being earthed by just a foot of thick braid - the instructor demonstrated that just flexing the shock mounts so the bolts touched was sufficient to make it work. Just that foot of braid had enough inductance to prevent it conducting the interference well.

As a more extreme example, even more jobs ago, a customer brought in a laptop for repair. He was working in Madagascar at the time, and they have "proper" thunderstorms It was clear that the surge had come in via the phone line - chips were blown apart on the modem card. It had then arced across to another board in the laptop - we could see the scorch marks. We thing the surge had then gone to mains/earth via the printer which used to have a "brick in the cable" power supply. I say used to as the case was blown wide open exposing the internals. It wasn't a cheap job getting him back to a working setup
But what annoyed him most was that a table lamp plugged into the same socket, and a phone plugged into the same phone line, were both perfectly fine !

But back to the OPs question ...
Such an extension lead will, if used correctly, help protect stuff. To use it correctly, you have to treat a group of equipment like the whole house I described above - everything for that group of equipment must pass through the same protection point. So ideal for the situation common just a few years ago when you'd have a single PC, monitor, printer, and modem. Plug all of these into the surge protected extension, and route the phone line through the provided sockets as well. Then you have an island where everything has a single earth point for it's protection - even though that earth point may be hundred or thousands of volts from normal earth potential during a surge.