+1

A lot of expense to go to for galvanic isolation with otherwise zero benefits of a fibre connection to my mind.

But I respect the OPs choice. So remains otherwise shtum 😂

There is no benefit to a fibre connection, other than galvanic isolation, since the rest of the network is limited by being CAT6. The expense looks similar to the expense of running fibre over the whole route. Fibre over the whole route confers no benefit and the disbenefit of requiring pre terminated cables.

In reply to a post by tdw42:

In reply to a post by DFScale:

Sorry, I got carried away. My electrics are T-NS, but we are bonded as though T-NCS.

Either still have a direct bond between the two ends.

Re the isolation, how is this achieved? Are the RJ45's connected to little signal transformers or capacitors with a good voltage rating?

Both, the data passes through transformers, the termination ground has a capacitor to the local signal ground. See Figure 7 in https://resources.altium.com/p/gigabit-ethernet-101-... as an example.

Even PoE is galvanically isolated, the device power supply electronics have an output transformer so again there no connection between the cable and generated supply.

Ah, thanks for this. I have taken a brief look which addresses some of the concerns, but I need a deeper look.

Spikes are incidental and separate from the 10baseT Ethernet connections. I should have mentioned that

Both buildings have mains Section 19 fuse boxes, and supply from the main property supply.

At some point I investigated having a separate 3 phase supply to the garage, as the last pole for the supply is next to the garage. I was looking at piece of 3 phase equipment for the garage.

When I installed the new supply to the "cabin", I had issues with it tripping the RCD in the house (not the 2 others the supply was going through). To try to alleviate these (and an earthing issue) I added the earth spikes. The spikes were cheap and easy, but not the solution.

Re: isolation , as tdw42 points out, Ethernet over UTP doesn't require this, having inbuilt isolation in the standard.

I have/had a stack of 10GbE and 40GbE fibre equipment but decided it would be OTT to install fibre in a domestic environment. I think this is still the case. 1GbaseT is almost free, 2.5GbaseT is cheap as chips. Even 10GbaseT is reasonable.

1GbE over UTP is perfectly adequate, utilises very cheap cable is easily installed, tested and maintained.

My only wish is that I'd pulled a second Cat 5E cable, (or Cat6) for a separate PoE WiFi. I have this everywhere else, driven by a central switch (on a UPS, together with main router). This is what I have elsewhere, as we have no phone reception and rely on WiFi/WiFi-calling/VoIP for all phone communication.

In reply to a post by fleddy:

I have an outbuildings >100m from house. I used CAT5E I get 1GbE across to it no problem, with a patch panel connection at each end. The cable is available from screws and the like for not much money. It does have a separate earth spike,.

It passes through my garage, where one of the patch panels is. This is 20m .from the house, I get 2.5GbE to the garage,,along same cable, without any patch panel links. Again another earth spike.

I think 1000feet of cable was <£30.

That's an entire 305m box, If you paid that little then it isn't Cat5e.

The specs for Cat5(e), 6(a), 7, 8 etc. state the conductors are to be pure copper, anything considerably cheaper than £100 per box these days will be copper clad aluminium (aka Counterfeit Cat5/6) and will cause no end of issues. The diameter of the conductors (AWG - lower number is thicker) is likely to be less too so resistance will be increased, on top of the increased resistance by dint of them being aluminium.

The weight of the box will be the dead giveaway, or having CCA printed on the cable (not to be confused with Cca fire compliance rating).

Edited by _KP_ (Sun 02-Mar-25 20:20:52)