Supply fuse

[JohnW2]

One of the problems with offering assistance or opinions on a DIY forum is that it has to be a case of "do what we say rather than do what we do". We all take (calculated) risks but it's a grey area when we suggest others do likewise since such suggestions might come back and bite.

Indeed so - and even when it's things that 'we all do' (but shouldn't), it's not usually appropriate to suggest, let alone 'advise', that others should do it (in context, particularly 'DIYers'). At least when 'we' do things, we are hopefully fully understanding of whatever risks we might be taking - someone with less knowledge may well not have such understanding!

Hell, I don't know why I'm still alive when I think of the stupid and not-so-stupid things I've done in my lifetime. Having survived (so far) the lessons learned from such events doesn't mean I'd recommend others to try doing likewise.

I suspect that there are few of us who couldn't say much the same.

Kind Regards, John

 

[skotl]

Please read that very carefully!
You are not trained
You are not legally authorised
You will not have the appropriate protective equipment
You do not know what hazards to look for
To be allowed to open or work within that cut-out. Once the fuse is removed it WILL expose a live terminal that may be protected by a fuse size up to 630A. Get it wrong at best you WILL be in hospital for a long time.

This seems to be a totally unnecessary knee-jerk! The OP said absolutely nothing to suggest that he had the slightest intention of touching the cut-out himself. His one and only question was whether the "supply company" would replace it free-of-charge or whether they would charge him for doing it!

Kind Regards, John

He has already admitted to opening the metal cover, he has already suggested that the fuse will be pulled to do the CU change. He has already stated that the tails will be changed by possibly entering the meter connections.

I would rather he gets used to the fact that he or an electrician shouldn't be doing any of this before he risks himself or another getting injured...

I have to say that I'm completely with Westie on this one. We have indeed all toyed with things that perhaps we shouldn't have, but this is definitely a step too far - the risk to life and property far exceeds what is typically discussed on this forum.

 

[RF Lighting]

I also agree. Whilst I am guilty of removing cutout fuses, and I know I shouldn't, I will not touch metal clad cutouts. It's simply too dangerous. Not only is there a risk of being killed in a molten copper fireball, they are also normally full of asbestos too, so to advise anyone, especially a DIYer to do anything other than to report it to their DNO goes against everything I beleive.

I recently reported a cutout the same as pictured in the OP to my DNO. Even they will not work on it. Instead they are going to cut the supply cable outside the property to allow them to replace the cutout safely.

 

[JohnW2]

This seems to be a totally unnecessary knee-jerk! ...

I have to say that I'm completely with Westie on this one. We have indeed all toyed with things that perhaps we shouldn't have, but this is definitely a step too far - the risk to life and property far exceeds what is typically discussed on this forum.

It would, IMO, have been perfectly reasonable for westie to have just pointed out that the OP should not have looked inside the cutout (because it was dangerous etc.) - but the rest of the 'lecture' seemed (again IMO) rather OTT to me, since there was absolutely no indication that the OP had any intention of touching it any further - he was merely asking whether or not the 'supplier' would charge for replacing it. However, opinions obviously vary.

Kind Regards, John

 

[ban-all-sheds]

This seems to be a totally unnecessary knee-jerk!

Not at all.

He opened the cutout.

He fully deserved everything Westie said.

And more.

 

[westie101]

Some instructions we work under to pondor

3. RECOGNITION OF DISTRESS OR INTERFERENCE
3.1 It is essential that all staff who are required to work on or test cut-outs shall be able to recognize evidence of distress to which a cut-out may have been subjected.
The following points need to be considered in making an assessment on the condition of a cut-out:
 Removal of or damage to security seals
 Observable significant physical damage to any of the components of the cut-out
 The existence of a recent fault condition
 An on-going no supply
 Evidence of overheating, including, discolouration of any of the connected cables or security blocks
 A slight smell of burning or evidence of burning/scorching to the Service Termination
board
 Discolouration of the cut-out contacts
 Discolouration of the fuse and fuse carrier
 Security of the wall fixings of Service Termination Board (formerly referred to as the Meter Board) or the fixing of cut-out to Service Termination Board
3.2 It is important to adopt a methodical approach to fault diagnosis by looking for evidence of distress at each stage including a visual inspection prior to the removal/replacement of the fuses.
3.3 When any evidence of distress is identified, further work or testing shall only be carried out by a suitably trained Competent Person with the appropriate operational authorisation who shall decide whether or not the cut-out needs to be made Dead.

6. PERSONAL PROTECTIVE EQUIPMENT (PPE)
Precautions for working on Live LV cables are specified in the Distribution Safety Rules
(Rule 8.6.2) and Explanatory Note 20. Personal Protective Equipment which is
appropriate to the risk shall be worn when working on Live cut-outs. It is a requirement
of CP606 Procedure G19 that arc resistant coveralls are worn for all LV operational work and work at LV cut-outs. Additional protective equipment is required as follows:-
6.1 For work on the outgoing terminals only: approved eye protection and protective gloves shall be worn for the removal of the fuse and up to the stage when all Live metal has been shrouded. This additional PPE shall again be worn for the replacement of the fuse.
6.2 For cut-out replacement work, work on the Live contact of a cut-out or in cases where possible distress or supply failure is being investigated – an approved face screen (visor) constructed with no metal parts shall be worn together with approved insulated gloves plus the protective kid leather overglove.
These shall be worn for the removal of the fuse and up to the stage when all Live metal has been shrouded. This additional PPE shall again be worn for the replacement of the fuse.

7. SHROUDING OF LIVE TERMINALS
7.1 When a cut-out fuse carrier is removed the Live fixed contact shall be shrouded as soon as possible.

7.2 Wherever possible the shrouding of the Live fixed contact shall be done using a proprietary shroud. Where a proprietary shroud does not exist it may be possible to manufacture a device by cutting a cut-out fuse carrier in half and blanking the cut end in such a way that when the half carrier is inserted in the Live fixed contact the half carrier completely shrouds the Live metalwork. This would be acceptable for the majority of cutouts in service

Looking at the photos it looks as if it is quite possible that the one shown may be of a type we are not permitted (this DNO) to work upon whilst live IN ANY CIRCUMSTANCES, as the hinged cover looks to be removable!

These cut-outs are all generally in excess of 50 - 60 years old and some date to before WW2.
For anyone that is untrained to open them or interfere with them is potentially a serious safety matter so we do not play "the nice guy" in any circumstances. It's better to cause some upset than to pick up the pieces afterwards.

Though, despite their age if they are left alone and only dealt with by trained staff they are fine.

As a point I've noticed a few times that some customers seem to think the device is their property and they have the right to interfere with it. As we all know it is not and they don't

 

[JohnW2]

We don't know (and may well never know) how much, if any, of this discussion the OP has seen (other than Jackrae's initial response), since he hasn't been seen again since westie posted his first message in the thread.

Kind Regards, John

 

[RF Lighting]

He probably killed himself messing with that ancient cutout...

 

[JohnW2]

He probably killed himself messing with that ancient cutout...

Not impossible, but very unlikely, given that we have no reason to think that the OP was ever going to go anywhere near the cutout again.

Although the OP has been given (if he's read it) some very important safety information, his questions have not really been answered. The nearest to attempts to answer his questions were the first two responses, which were somewhat contradictory. The first questioned the need to change the cutout ("fuse") and said that if it were changed, the OP would probably be charged. The second suggested that he contacted the DNO to get it replaced, and said (I would assume correctly) that this would be done without charge.

Perhaps without realising it, the OP may well have been asking an important question. In order for the OP's work to be done, the cutout fuse will have to be pulled at some point in time, and westie has suggested that the cutout "quite possibly is" of a type from which even DNO personnel would not be prepared/allowed to remove the fuse. If that is (or may be) the case, then the OP should be advised to first ask the DNO to 'upgrade' the cutout (as the OP more-or-less suggested/asked), in order to facilitate the subsequent pulling of the fuse.

Kind Regards, John

 

[Graham3232]

I’ve seen one of these old 1920/30s metal cut-outs go bang before, it was like a bomb going off and made a right mess! It just arced away until the cable melted. Fortunately no one was near at the time.

I also just has one changed the other day by Northern Power Grid. Just tell them you are planning a rewire and or the meter fitter refused to change the meter due to the age of the cut out. They will usually send a surveyor round same day and a contractor round usually next day to replace it with a modern plastic one and provide a proper earth terminal (assuming TNS earth onto the lead sheath). They will also dig the street outside to make the cable dead before changing metal cut-outs. There will be no cost to you as it is their network/equipment.

There was an old notice stuck to the wooden backboard ‘in the event of equipment or electricity faults, send a postcard to the local electricity office stating your address’. Those were the days

 

[Iggifer]

I recently had WPD change one of these - there was a grommet missing in the top so used that as an excuse to get them out - knowing full well they would just change the cut out.

They smashed the thing to f**k to replace it, rather than try and remove the cable from it.

Says something about how dangerous these cutouts can be/are

 

[JohnW2]

They smashed the thing to f**k to replace it, rather than try and remove the cable from it.

Whilst the cable was still live? !!!!

Kind Regards, John

 

[RF Lighting]

That's how my DNO used to do it. They would carefully smash the cast iron and ceramic to remove it in pieces from around the cable. They no longer do this, and cut the cable outside in the street instead.

 

[JohnW2]

That's how my DNO used to do it. They would carefully smash the cast iron and ceramic to remove it in pieces from around the cable.

Hmmmm ... interesting! How could they be sure that such a 'brute force and ignorance' approach was not going to result in the L & N conductors coming into contact, with all the possible consequences that people here have been warning about?

They no longer do this, and cut the cable outside in the street instead.

That sounds much more sensible!

Kind Regards, John

 

[Adam_151]

Hmmmm ... interesting! How could they be sure that such a 'brute force and ignorance' approach was not going to result in the L & N conductors coming into contact, with all the possible consequences that people here have been warning about?

I imagine it was probably a case of cracking the section that is filled with pitch first and then opening it like an egg away from the fuse contact.

I imagine that with PPE and a jointer who'd been doing them that way for years accidents were reasonably far between, but still possible on occasion which I presume is why the practice has been stopped.