FTTP coax filter suddenly live 110v AC....tingly!!!

[Northernboater]

So, I have FTTP, hub3.0

Usual filter between the wall plate and the router(modem in my case!).  Got bit of a zap from it today whilst moving some stuff around. 

Multimeter shows the filter body as 110v to earth. 

Tested the outside of the F connector at the power supply that feeds the wall plate, also 110v to earth, also giving mild shocks. 

I've tested all my other kit, all fine. How do I get a new power supply without 17 hours of explaining it via virgin media chat?

[goslow]

If you mean this kind of power supply

https://community.virginmedia.com/t5/Forum-Archive/ONU-power-supply/m-p/5213491

I think that has to be via a tech visit.

[Northernboater]

Yeah it is one of those. Not sure why they decided to use coax for a 500ma 12vdc power supply in the first place - could have been run from the main router power supply which is 2.5a 12vdc. 

Anyway, back to the problem. Surely VM can just put one in the post? Or upgrade me to a new hub?

[goslow]

Seemingly not available to post AFAIK (one past topic on here went on for 2 weeks while the customer tried to get one sent before it was eventually established a tech visit was required).

https://community.virginmedia.com/t5/Forum-Archive/ONU-Power-Supply/td-p/5235411

In any event, you may need a tech visit for the voltage issue.

Have you done the test(s) to earth when the power supply is turned off (to confirm it is a power supply fault) and that you are not importing the voltage from outside your home somehow and/or you have an isolator problem.

[Cardiffman282]

Re the anticipated tech visit make sure you are not stung with a £25 charge. 

[Roger_Gooner]

It's coax because it goes into the internal termination box which also contains the coax from the ONT, so it's a clean all-coax installation.

[Northernboater]

So, it's a class 2 supply, so no earth - the pin is plastic. That rules out my earth being juicy - although earth and neutral will be connected together somewhere down the line!

It's likely just a bit 'leaky' - very low current. I do have other mains DC supplies that show 120vac, but they don't tingle 😉

[goslow · Accepted solution]

Where/how/between what are you measuring the 110V ac?

[Roger_Gooner]

You have to despair when a FT member doesn't understand that fixing a fault caused by VM is FOC.

[Northernboater]

Well, it's from the "ground" of the PSU, so it's irrelevant where it's measured on the VM side - but between the ground of the PSU and my house earth, first time round was a bonded radiator tail, thereafter direct to mains earth. 

I've done some more probing(see what I did?) and I think this is probably a common thing from these cheap PSU's. Anyone wanna go measure theirs? Live mains leakage to DC ground  - I guess mine is just a big more leaky than it used to be. Still, It's right next to my pc, so I'd much rather there was zero leakage!