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Non contact methods to check overhead HT powerlines?

UK had a bit of a battering recently with storm Arwen and many areas including mine were off grid for a few days to a fortnight. This was largely due to the utter incompetence of one power distribution network at dealing with the many faults it caused. Most of them look to have been due to avoiding doing any kind of preventative maintenance.

A big problem was persuading the engineers sent out to fix things that the main distribution 11kV and 33kV lines were down rather than the LT

240v mains systems in the villages. They even insisted on checking mains fuses and drop lines to premises before they would even consider looking at the next level up. It was incredibly frustrating for all concerned.

The field engineers were being told by their central system that these locations were on grid (and calls were logged as if this were true so that individual premises were marked as needing a reset). The reality was that a tree had snapped the HT line in a very difficult to see spot and there were lines trailing on the ground elsewhere too. The farmer even reported this on the first day as a danger to life fault.

This was repeated all across the North of England and some places had still not had power restored when the next storm Barra hit yesterday!

What would be incredibly useful would be to have a quick none contact means to establish if 11kV or 33kV lines are live or not by standing underneath with a small simple box. I have in mind something like a high gain audio amplifier and a mains hum wet finger test. Any better ideas?

I know that for the next level up you can get fluorescent tubes to glow in the electric field under 200kV pylons, but they are bit fragile.

Does something easy like this already exist? If not why not?

Understandably in the pitch dark, foul weather and a howling gale field engineers are not keen to use a hook on probe just in case it is live.

Reply to
Martin Brown
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I'm sure they have hi tech detectors as opposed to a box and a finger.... And when they do start work, they strap the conductors together and bond them into the ground, just in case...

Reply to
TTman

A neon bulb on a plastic stick ought to work.

Reply to
Liz Tuddenham

They gave the strong impression of not knowing which way was *UP*!

Reply to
Martin Brown

In the rain!

My OEM Japanese AM car radio distorts whenever I pass under a major power corridor. Funny, a Korean one in SO's PHEV doesn't.

Reply to
Spehro Pefhany

Hang cats on the line.

Reply to
Fred Bloggs

Possibly the helpdesk needs more training they could have asked "do your neighbours have electricity"

A field mill.

Reply to
Jasen Betts

Smart meters and a GIS. As smart meters send a "last gasp" message on a power fail, the network operator can easily see: all consumers behind a certain location on the HV line are without power. That should narrow the problem quite a bit. AFAIK, the UK already has quite a few smart meters in use. The maintenance of the GIS is often the problem.

Wim Disclaimer: I manufactured these before my retirement.

Reply to
Wim Ton

The hell desk is a f*cking Dalek designed by clueless idiots. (I am writing to my MP about it - there will be a public enquiry)

There is a long preamble about much they care about their customers and how you can check on the website (well no you can't because mobile and fixed line internet both go down very quickly without any mains).

The only two questions you can get to via a POTS phone line when their system thinks that your segment is on power are:

Do you have mains power ? YES/NO Have you checked your main breaker? YES/NO

It then says you can stay on the line to talk to an advisor. The waiting time for this is <X> minute (X is never small). You sit on the line for that time waiting and then they drop the line at their end.

Rinse and repeat...

They didn't seem to have anything or they wouldn't have spent so much time pratting around checking house internal wiring. The house they went to had a 11kV line and transformer about 30m from the front door.

Remember their system is telling them the HT circuit for this segment is OK. The customer is telling them *NO* the whole village is off. The engineers were stuck following their inflexible tick box automated protocol - but they didn't seem very bright at fault finding either :( They would have charged him £180 if he refused to let them check his electrics - I might have been inclined to say OK see you in court.

They were a bit unlucky that the house they picked was one of two isolated ones nearest the main road with no street lights outside. If they had picked me first in the village I could have demonstrated conclusively that all phases were down since the street lamps were off.

By the time they eventually reached the village centre the streetlamps would be off anyway since they are smart ones that shutdown at midnight.

Reply to
Martin Brown

In this case I think we can be fairly sure it was human error. I'd have expected them to be able to tell from the control room which HT breakers were off in real time - but perhaps my expectation is unreasonable.

The one causing the trouble was difficult to get to - my suspicion is a CBA failure and ticking the box to say it was OK without going to look.

There aren't many smart meters in rural UK mobile signal too dodgy.

There is one in our VH installed at the start of lockdown. It lost contact with base after 3 months. They replaced it and gave it a super antenna on a longish wire and that failed after another 2 months. They have gone back to manual electric meter readings after that.

My own home can't have one either for similar reasons - not enough mobile signal strength indoors for ET to phone home. My mobile only gets enough signal if placed on a particular window ledge and on bad days for

2FA to work I have to walk around the garden holding it in the air! (sometimes the website times out before I get my one time code)

In this case it looks very much like they maximised company profits by failing to do any routine maintenance at all on the physical network. In places one pole falling over caused a cascade failure of dozens of adjacent poles that were all basically at end of life. They fell down like dominoes once the first one went down. Here is a bit of background:

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In the same field as the one that snapped we have found another pole where beast rubbing against it have thinned it to a mere 4" diameter at cow shoulder height from a starting diameter of 10".

Reply to
Martin Brown

High Tech can't cure stoopid...

Reply to
David Lesher

David Lesher snipped-for-privacy@panix.com wrote in news:stmuhg$cre$1 @reader1.panix.com:

IR thermometry does it. Now, imagery.

Way back in '86 I used to make a 4 inch tube x about 26" length with a rifle stock attached to the bottom/rear, and a rifle scope 'prismed' right in to the exact aim point. And it had an analog dial scale up to

450F if I recall. And it was a Gold 4" mirror and single resistor bolometer IR transducer with a Germanium 2mm window on a TO-39 can. The power companies bought them to point at insulators and transfrmers from a distance without the need for a bucket truck or other hazardous method. All before small form factor room temp imaging instruments came out. Now one can buy an IR imaging thermal 'camara' for a couple hundred buckaneers! and a brand name one for not much more.
Reply to
DecadentLinuxUserNumeroUno

snipped-for-privacy@decadence.org wrote in news:stn09q$bp$ snipped-for-privacy@gioia.aioe.org:

snip

Here is the handheld unit. Mine had a 4" tube and a rifle stock, but I could not find one out there

formatting link

I can't find the long tube job I used to make, but I made a few of those I posted the image of as well.

Reply to
DecadentLinuxUserNumeroUno

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