Rules and Guidelines
Want to participate in the discussions? Please read our Community Rules and Guidelines. Need some help? Visit Support and Answers.

  • State Not Answered
  • Locked Locked
  • Replies 110 replies
  • Subscribers 32 subscribers
  • Views 18443 views
  • Users 0 members are here
Options
You may also be interested in
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

On the subject of pulling the DNO fuse.

alanblaby
There have been a couple of reports here of the DNO confronting electricians who have pulled their fuse.


It's getting closer to home, a work colleague was doing a CU change on a domestic house last week, no isolator fitted, so he pulled the fuse (no seals present).

South Nottinghamshire.


Around 90 minutes later there was a knock on the door, a guy from Western Power was investigating a power loss at the property, reported by the Smart Meter phoning home.

He gave the sparky a talking to, and warned they are getting strict in pursuing people who do it, he said meter fiddling was rife, so any loss of power is checked out asap.
  • 0
    I think we are all agreed pulling DNO fuses is not a good idea I think that we need for them to understand that sometimes it's unavoidable due to circumstances  I get why it's not allowed  I think the main concern is if its done to enable someone to steel electricity. But I understand that in some substations there are KWh meters which record the consumption of all the customers on it  so if they suspect steeling surely they can add up all the meter readings for a given area subtract that from the subs meter and after allowing for street furniture use if it don't add up correctly they know someone's on the fiddle then you hey can look more closely instead of being on our backs every time we pull a fuse
  • 0
    Just a random thought ...


    Almost new fuse holder secured to a board which is in good condition and is easily accessible. Not a lot of danger.


    Old service head on a tatty old board with multiple redundant screw holes in a damp poorly lit cellar. That's when you need to get out your arc shield and marigolds.


    I think that you have to have one clear rule and "don't touch" is easiest. Or you could, like SSE, trust properly credentialed electricians.
  • 0

    Kelly Marie:

    I think we are all agreed pulling DNO fuses is not a good idea I think that we need for them to understand that sometimes it's unavoidable due to circumstances. . . 




    There are virtually no circumstances when it is allowable. The fuse belongs to neither the electrician nor the householder and it should not be touched. All DNOs have a procedure for them to temporarily isolate the supply, and the HSE believe that this method of working - arranging for the DNO / Meter Operator to draw the fuse is acceptable. It is good that companies like WPD are able to spot tampers with the new smart meters, as well as being able to investigate them immediately. 


    Regards,


    Alan. 

  • 0

    Chris Pearson:

    . . . Almost new fuse holder secured to a board which is in good condition and is easily accessible. Not a lot of danger. . . 




    Have you ever seen a faulty cutout “let go” whilst being fairly near it? It is incredibly frightening, and surprising how long it will burn for, throwing molten metal at anyone in range. An electrical arc flash has a temperature hotter than the surface of the sun, and an explosive force of several sticks of dynamite. You really don’t want to discover it in the cupboard under the stairs, or anywhere else for that matter. . . 


    Regards,


    Alan. 

  • 0
    Perhaps such dangerous equipment in people's homes should have been maintained properly and replaced by the 'owners' before getting into that condition.
  • 0

    geoffsd:

    Perhaps such dangerous equipment in people's homes should have been maintained properly and replaced by the 'owners' before getting into that condition.




    Well said Sir, well said.


    Z.

  • 0

    Have you ever seen a faulty cutout “let go” whilst being fairly near it? It is incredibly frightening, and surprising how long it will burn for, throwing molten metal at anyone in range. An electrical arc flash has a temperature hotter than the surface of the sun, and an explosive force of several sticks of dynamite. You really don’t want to discover it in the cupboard under the stairs, or anywhere else for that matter. . . 



    It's not my field but I was told by a lecturer on protection course last year that DNO disconnection times are rather longer than BS7671 and indeed the design of some LV distribution systems is intended to have the cable burn back within the insulation/sheath and extinguish itself before the substation fuse operates, meaning other customers remain connected. Which is fine buried underground well away from people, but means the risk assessment for a live cutout in a building is a bit different to pulling a fuse in "normal circumstances"
  • 0
    Indeed. An aluminium conductor will burn back down into the insulation until it goes out (which could be a long way from what is believed to be the cable end). A copper conductor is likely to just burn until hopefully a fuse operates, as copper has a much higher melting point. 


    Regards,


    Alan.
  • 0
    With all this talk about protective equipment, I had a smart meter fitted a couple of weeks ago (1960's property, WPD is the DNO).  No sign of PPE to pull the fuses, not even gloves.


    David
  • 0

    Arran Cameron:

    What is the situation like in other countries? Are electricians and homeowners allowed to remove the DNO fuse?


    Has anybody actually seen an arc flash caused by shorting out a service head?



    Here in sunny Thailand there's no such animal as a DNO fuse, the wires in your incoming MCB (or fused knife switch) go directly to the meter (on a pole in the street) and thence to the local transformer.


    Want to work dead on your installation? Pull the live tail out of the meter (seals? what seals?) and do the deed. When done poke the wires back in and you're good to go.


Community Rules & Guidelines