Fused neutral cut-out

[monoloco]

Apologies if this isn't the appropriate bit of the forum to post this to, or for any uneducated comments in what follows - straying beyond my elec expertise!

We had our meter changed over to a digital one the other day & the guy who did it spotted we had an old fused neutral cut-out. So Western Power Distribution have been out today wanting to replace it.

I understand enough to appreciate it needs replacing (not that I'd personally be fiddling with wires to come a cropper if the neutral fuse did get blown), but they're saying they need to dig up w nice hole/trench in our (recently tarmaced) driveway to fix it.

Is there a good reason why the service head couldn't safely be replaced without doing that, or is it genuinely unavoidable?

I just want to make sure they're not doing the thing that's easiest/cheapest for them, but not best for us!

Thanks!

 

[Plonker 3]

The swapping of your cut out should not involve digging anything up. You should phone them and find out exactly why they need to dig it up and post back what they tell you.

 

[ipf]

Can't get why they want to dig your drive up to change a cut out.

 

[monoloco]

I'm not sure either - they didn't explain to my wife.

How would they usually isolate it to swap the head (or is that not necessary)?

 

[Andy78]

Only reasons I can think of is to extend the service cable to facilitate the head change, or t repair a section of damaged cable identified on the survey.
Whatever the reason, we can only guess, and as Dillb says only the DNO can answer this.

 

[UKMeterman]

Some of the old cutouts are in a very poor state, and have lots of earth metal that can't be made earth free. The only way to work on it safely is to cut off the supply, hence hole in drive or road.

 

[monoloco]

Thanks all.

I'll give them a call and report back.

If it helps to see the cut-out then here's a picture of the offending item!

 

[Knobhead]

There are ways of doing it BUT to do it safely there isn’t. The DNO’s are obliged to change these heads, at one time they’d modify them.

Post a picture on something like photo bucket and link it to here. If there’s sufficient length on the incomer it can be done, near the floor, forget it.

Do you really appreciate why the neutral shouldn’t be fused?

Pity you only put UK as your location. Some systems were originally DC and converted to AC at a later date. I’m particularly interested in these systems as I’ve lived in two houses that were originally DC. One +ve the other –ve, they were next door to each other.

 

[davesparks]

I've got the manual for how to install that isco cutout if that's any help?

 

[monoloco]

Thanks Tony. Is that photo I've posted visible?

There's only a couple of inches more of the incomer exposed below what you can see there.

As for whether I really appreciate why the neutral shouldn't be fused - as I suggested, this definitely ain't my specialist subject, but I get that the fuse could blow and leave you not realising the circuit's still hot.

Can you explain how it's help to know my location? We're in Gloucestershire - a 1930's house.

 

[monoloco]

Dave - maybe?? Will almost certainly be double-Dutch to me though! :sick:

 

[PEG]

That cut-out looks very similar to those fitted on 1930's properties,where,on occasion,the DNO or their agents do fit a joint in preference to working on an old unit.

On my own 1937 property,they renewed the head,no problems,in about an hour,but my pal,on the same road,had a joint put in,about a meter from the cut-out.

I inspected his cut-out, previous to this work,and it looked no worse than mine. I think a lot depends on the crew that turn up,and what mood they are in,as when i mentioned this to the lads that did mine,they told me the other crew must "sit down to have a wee"...(actual quote) :jester:

 

[davesparks]

It goes without saying that you must not in any way attempt to even open that cutout, let alone do anything else to it.
But for anyone who is interested here's a few pages from the book.


And if you are wondering what tools the modern cable jointer might require to practise his trade, here's the list.

 

[ipf]

A Ze reading would be interesting.

 

[Knobhead]

It would be interesting but a bit out of the scope of the OP

 

[driverman]

Re cut out change........as said earlier..DNO safe practice.....work on head dead. In order to do that joint hole required. However, as you mentioned new tarmac, ask the DNO to do the joint hole elsewhere. that may well mean doing on the public footpath ( assuming there is one) where your service cable is.

 

[Plonker 3]

Re cut out change........as said earlier..DNO safe practice.....work on head dead. In order to do that joint hole required. However, as you mentioned new tarmac, ask the DNO to do the joint hole elsewhere. that may well mean doing on the public footpath ( assuming there is one) where your service cable is.

sorry I dont follow, how are they going to isolate the head without working live?

 

[gnselectricals]

There's less risk by chopping the cable in the street than working on a metal cutout live I believe

 

[driverman]

sorry I dont follow, how are they going to isolate the head without working live?

Hi Dillb, On the face of it, it may sound strange. However it is deemed to be much safer to dig joint hole, cut cable safely, so as to make safe the cutout to work on. Yes, years ago jointers would off worked on the head live. i suppose it safer to work on the separate cores dead as opposed live. Has been that practice for many years. I had to inform customers exactly that whilst I worked for a DNO service alterations. Like the OP's case above....... i would try to avoid sensitive areas like the tarmac.but your governed by the existing service route.

 

[7029 dave]

Hi Dillb, On the face of it, it may sound strange. However it is deemed to be much safer to dig joint hole, cut cable safely, so as to make safe the cutout to work on. Yes, years ago jointers would off worked on the head live. i suppose it safer to work on the separate cores dead as opposed live. Has been that practice for many years. I had to inform customers exactly that whilst I worked for a DNO service alterations. Like the OP's case above....... i would try to avoid sensitive areas like the tarmac.but your governed by the existing service route.

Yep, they always ditch the cable on my patch too, on cut out changes.

 

[mechelec]

I believe WPD jointers need specific authorisation to replace metal clad cut outs live. Not everyone has it and a risk assessment is carried out on each one before it is changed. Risk assessments being subjective and every person being different what one deems to be OK to change live another will want dead (ie service cutting outside)

 

[monoloco]

Thanks all!

So it sounds like it depends on their risk appetite & is potentially quite valid for them to say they need to dig outside.

I'll see what options they can suggest for a hole that doesn't wreck our driveway (though unfortunately there's no pavement outside - it's our Tarmac straight to the road).

Should i expect them to have a good record of where the service cable runs?

and on a slightly different note, the house was gutted & renovated in 2011, with all the electrics (on consumer side of the meter) completely replaced. Was it valid for that work to be certified with the fused neutral cut-out left in place? (does that certification only consider consumer-side bits, with meter, service head, etc handled totally independently under DNO regs??)

 

[davesparks]

They won't have the faintest idea where the service cable is!

 

[monoloco]

I thought that might be the case! :nonod::nonod:

 

[UKMeterman]

If you ask them they can trace the service cable with a cable location tool, I know this as I used to work in the Radiodetection design office. Should be able to trace it back to the street without needing to dig.

 

[PEG]

It goes without saying that you must not in any way attempt to even open that cutout, let alone do anything else to it.
But for anyone who is interested here's a few pages from the book.
View attachment 28870
View attachment 28871
And if you are wondering what tools the modern cable jointer might require to practise his trade, here's the list.
View attachment 28872
View attachment 28873

Love it...you would enjoy my book collection! ...only bit that let it down,was the ball "pane" hammer...not seen one of them...:yes:

 

[davesparks]

Love it...you would enjoy my book collection! ...only bit that let it down,was the ball "pane" hammer...not seen one of them...:yes:

Yes, I noticed that one, it's a bit late to tell the publishers though!

That book is WT Henley's 'practical cable jointing' fifth edition published 1940.

 

[PEG]

Yes, I noticed that one, it's a bit late to tell the publishers though!

That book is WT Henley's 'practical cable jointing' fifth edition published 1940.

Not got that particular journal,but i do have the appropriate Buck and Hickman catalogue,with most of the equipment listed for sale...i also have a collection of vintage tools,including joint box casts,for bitumen,and even a 9lb lead mould,for casting a "tee" on a water pipe,to save all that wiping!

...Born too late...i fear my lads first phone call,the day after my service...will be to the scrap-man...:smile5:

 

[davesparks]

...Born too late..

You and me both!

 

[Knobhead]

I was surprised to see you can still get CI through and breach joints for 11KV PILC-SWA. When I went to the EMEB I had to take one with me, EMEB didn’t use them but we did. The company still use them to this day.

I’ve never done an 11KV breach joint and I’ll be honest I wouldn’t even attempt one. There’s about 5ft of wiped joints around the lead sleeve. I’d be happy doing a modern breach using a cast resin joint.

I’ve still got my apprentice log books. There’s an entry 11/02/74 for a 11KV termination, 23/07/74 3.3KV through joint and 30/08/74 11KV through joint. A lot of my time was sat in muddy holes.

 

[driverman]

Thanks all!

So it sounds like it depends on their risk appetite & is potentially quite valid for them to say they need to dig outside.

I'll see what options they can suggest for a hole that doesn't wreck our driveway (though unfortunately there's no pavement outside - it's our Tarmac straight to the road).

Should i expect them to have a good record of where the service cable runs?

and on a slightly different note, the house was gutted & renovated in 2011, with all the electrics (on consumer side of the meter) completely replaced. Was it valid for that work to be certified with the fused neutral cut-out left in place? (does that certification only consider consumer-side bits, with meter, service head, etc handled totally independently under DNO regs??)

Let the forum know the out come please. Regardless of the neutral issue, as it is a metal clad cut -out, it wants changing anyhow by the DNO's own standards. The DNO should of been informed it was metal when the meter was changed. Meter fixers are not supposed to remove metal lid in order to remove fuse.

 

[monoloco]

Will do. Haven't managed to speak to anyone at DNO yet who knows what they're talking about, just their call centre. Will update after I call the local team in office hours this week and get it sorted.

 

[driverman]

Will do. Haven't managed to speak to anyone at DNO yet who knows what they're talking about, just their call centre. Will update after I call the local team in office hours this week and get it sorted.

When you have all info at hand and they still want to dig up the new tarmac that you have recently laid. Ask them instead of digging a joint hole in order to make safe your cable, ask them to carry out a local shutdown procedure. That means shutting down other properties also by giving them notice, possibly several weeks. There fore no need to dig up the tarmac.....Worth a try

 

[mechelec]

When you have all info at hand and they still want to dig up the new tarmac that you have recently laid. Ask them instead of digging a joint hole in order to make safe your cable, ask them to carry out a local shutdown procedure. That means shutting down other properties also by giving them notice, possibly several weeks. There fore no need to dig up the tarmac.....Worth a try

if it's a pole TX with two customers on maybe but not if it will affect any more customers.

 

[Knobhead]

When you have all info at hand and they still want to dig up the new tarmac that you have recently laid. Ask them instead of digging a joint hole in order to make safe your cable, ask them to carry out a local shutdown procedure. That means shutting down other properties also by giving them notice, possibly several weeks. There fore no need to dig up the tarmac.....Worth a try

And the cost? A couple of bags of cold roll is far cheaper.

The OP has to realise that the H&S of the DNO’s employees has a higher priority than his damned driveway.

 

[UKMeterman]

The op may wish to search YouTube for arc flash. This will give an idea of what can happen when things go wrong

 

[Knobhead]

Nice one, make the bags of cold roll a hell of a lot more palatable.

 

[monoloco]

And the cost? A couple of bags of cold roll is far cheaper.

The OP has to realise that the H&S of the DNO’s employees has a higher priority than his damned driveway.

Tony - I don't know if you're more polite in person, and manners just get lost behind the safety of your keyboard??

As I said in my original question, I came here to find out if there was a valid need to dig the joint hole, and as per my later reply I recognise, based on all the helpful replies, that there is (though might also be equally safe options that involve digging a hole in road surface that's already wrecked and pot holed by prev utility company work...)

and as for the local shutdown option - they just did it on Friday for a (unknown, but only 10mins) job on something in our local supply. So can't do any harm to ask.

 

[SPARTYKUS]

Ahhh TNS earth. Tell them to leave it as it is but change head, you'll never get one again. It'll probably be "upgraded" to the magic of the change of physics around the 50s/60s.

;-))

 

[driverman]

Tony - I don't know if you're more polite in person, and manners just get lost behind the safety of your keyboard??

As I said in my original question, I came here to find out if there was a valid need to dig the joint hole, and as per my later reply I recognise, based on all the helpful replies, that there is (though might also be equally safe options that involve digging a hole in road surface that's already wrecked and pot holed by prev utility company work...)

and as for the local shutdown option - they just did it on Friday for a (unknown, but only 10mins) job on something in our local supply. So can't do any harm to ask.

I think the DNO's are limited / restricted on how many planned shutdowns that can be carried out in same location, ie you wouldn't want your supply interrupted in a short space of time several times due to work going on locally. Emergency work of course is another matter. I would still go for the shutdown though. Don't forget, the DNO could of already of done the work, when their meter was changed

 

[monoloco]

I spoke to the DNO office yesterday and they were very helpful & forward leaning about finding a way to do it without a joint hole in the driveway. They want to come and have another look before deciding but volunteered that they had people that may be able to do it live, or with 2 weeks notice may be able to get the ok to dig on the road. They didn't rule out local shutdown, but we a bi hesitant about it due, as you say, to the Ofgen outage targets they're measured against.

Will update once they've visited and decided what to do.

 

[monoloco]

Came to see it today. Guy took one look and said it'll be no problem for him to do it live, and that he's qualified to do so, unlike the guys who originally came.

Due to do it next week (safely, I hope!).

Thanks for the all help / advice.

 

[monoloco]

Job done. Cut out replaced today, live, and safely.

 

[Leesparkykent]

Job done. Cut out replaced today, live, and safely.

Happy days, worked out well in the end.

 

[DPG]

Good to get feedback on what happened. Cheers. Daz