Pulling cutout fuses

[davesparks]

We see a lot of threads asking what to do about isolation for a CU replacement with lots of talk of the seal fairy and just getting on and pulling the fuse.
It gets me wondering whether you do the same outside of the domestic world?

Does the seal fairy visit the heavy duty (over 100A) cutouts as often in your experience?

And another related question, do DNO's replace larger cast iron cutouts as a rule the same way they do in domestic?

 

[DPG]

Is anyone else seeing loads of adverts mixed in with posts today?

 

[marconi]

If you do it - I would not and I recommend you do not - then at least make the effort to wear the appropriate PPE. I have used this company to equip personnel who connect high energy density batteries for 20 odd off-grid solar applications because of the very high short circuit currents. There are many others.:

Electric Arc Flash Protection Clothing | Electricity Safety - https://www.thesafetysupplycompany.co.uk/c/4536001/1/electric-arc-flash-protection-clothing.html

And this company provides insulated tools which we use to work on the batteries, inverters and solar arrays - again there are others:

Leading Manufacturer Of Insulated Live Work Tools - https://www.boddingtons-electrical.com/

What does your professional insurance stipulate you do or do not as a skilled competent person? In the world I once worked, an industrial setting, this work had to be done by the site's Approved Person (LV) or AP(HV).

 

[littlespark]

Hypothetically, you could pull a main fuse with no load whatsoever.
Domestic, that should be easy to trace tails to any downstream mainswitch and turn off.
Clamp meter to prove no current is flowing, then yank it out.

Depending on condition of fuseholder of course......

Tinkerbell doesn't need PPE

 

[Dustydazzler]

In a domestic you can just turn off the consumer unit at the main switch and then remove the cut out fuse without load...
I do carry insulated gauntlets to wear.
I have seen guys remove tails from electric meters while still live, which imo is more risky than pulling a cut out fuse...

 

[ChrisElectrical88]

In a domestic you can just turn off the consumer unit at the main switch and then remove the cut out fuse without load...
I do carry insulated gauntlets to wear.
I have seen guys remove tails from electric meters while still live, which imo is more risky than pulling a cut out fuse...

Seen this been done aswell. Not a fan.

 

[Dustydazzler]

Seen this been done aswell. Not a fan.

I once saw a time served sparks showing a 15 year old apprentice how to remove tails from a live meter...

 

[pc1966]

The DNO folk seem to pull/insert fuses on load, but rather them than me!

As said above, at the very least make sure the load is off. Worst thing you can do on accidentally inserting a fuse carrier on high load is to brick yourself and try to pull it out.

Most of the time folk don't think too much about clothing unless facing a real threat needing PPE, and for that you get proper arc-flash tops/trousers/etc. But one thing you ought to do anyway all the time you are working with possibly live systems is to wear natural materials such as cotton - yes it will burn under serious heat, but it won't melt and stick to your skin which makes any injuries much worse. Those polyester high-vis tops are a BAD idea here!

I have no idea what the DNO use in the way of PPE as it is not my area of work. In my case I have this for general head/face protection and it has some arc-flash rating:

TC42ESBJ | Penta White Safety Helmet with Chin Strap, Adjustable | RS

uk.rs-online.com

Most gloves for arc-flash are leather over a rubber insulating type, but you do get insulating gloves that have mechanical strength and arc-flash rating, mine are:

CATU CGM-00 Mechanical Insulated Gloves (500V) - Choice of Size

Insulated below 500V Work without leather overgloves Several sizes available

www.tester.co.uk

[automerge]1598293082[/automerge]
If you are getting overalls but don't need the full arc-flash rating that some jobs demand at the very least you can look at flame-retardant ones. Some are suitable for welding, etc, and go a long way to protecting you from small incidents, for example:

Men's Dungarees - Denim Dungarees & Overalls | Dickies® UK

Shop men's dungarees, overalls, boilersuits and coveralls. Browse a range of styles in denim or canvas with fully-functional features for casual or work wear.

www.dickiesworkwear.com

But of course if your job actually means PPE is needed then you should make damn sure the correct ratings of PPE are provided for you and they are looked after!

 

[freddo]

as much as I like fuse distribution boards like the MEM EXEL for their electrical protection I don't like pulling the fuses out.

I do miss the MEM boards with the red spot-finger shock fuses, so many have been replaced now. I don't miss the Kantark stuff so much, cool to look at but it's anyones guess if the old jammed in ceramic carrier will pull out without breaking.

 

[7029 dave]

Pulling fuses on any type of cutout, without the correct ppe is dangerous, the risk is even higher with industrial/commercial cutouts with j type fuses.
Please dont do it.!!

 

[littlespark]

Pulling fuses on any type of cutout, without the correct ppe is dangerous, the risk is even higher with industrial/commercial cutouts with j type fuses.
Please dont do it.!!

We dont....

Its the fairies

 

[Grant1987]

How bright is bright? Light can be measured in units known as lux, which is a measurement of illuminance and equal to 1 lumen per square meter. To put it into perspective, a typical overcast day is about 1,000 lux. Direct sunlight is upwards of 100,000 lux. The light intensity of an arc flash 3 meters from the source is over 1 million lux, and a more recent arc flash test recorded 13.1 million lux—approximately 130 times brighter than direct sunlight! Read that, now that’s bright

 

[pc1966]

The usual arc-flash threshold for PPE being necessary is 5 cal/cm2 as that is the onset of 3rd degree burns (i.e. not going to heal to as-before EVER).

To put that in to perspective, 1 cal/cm2 is roughly equivalent to holding a lighter on your skin for 1 sec!

 

[Dartlec]

Of course a sensible Government or Governing Body would have ensured by now that the smart meters being rolled out included an isolator, as some used to I believe.

Instead we have this situation where everyone knows what happens, but nods and winks and won't ever either ban it or put it in writing where it can be done.

I was told of a mythical scheme where certain competent persons could be trained and issued their own temporary fuse seals, which would be used when replacing the fuse - and then replaced when the DNO came along to check and replace with theirs. However, UKPN had never heard of it when I approached them, and were unable to give me any good advice on how to do things 'correctly' other than to point at the regulations.

 

[plugsandsparks]

Was watching NPG install a replacement 400A fuse at his sub and he used a device which plugged into the fuse carrier to make sure there was no or low load before inserting the fuse proper. Dont know what it was but it looked a bit technical to be nothing more than continuity tester.
He also wore full head gear , face shield and apron

 

[pc1966]

I have seen (product description, not first-hand) a fuse carrier for the 400A sort of range that allows remote connection of the fuse for safety, and to have two fuses so it can auto-reclose once to reduce fault outage time.

Forget where I saw it, alas