DNO Fuses etc

[hightower]

I'm now reading "Student's Guide to the IET Wiring Regs" and it's pretty good. But I'm on the point of responsibility and such. It states that the service head fuse should only be removed by the DNO, which got me wondering what people do to isolate the supply when they replace a consumer unit?

They go on to say it's quite good practice to fit an isolating switch between meter and consumer unit for this purpose, but if there isn't one fitted how do you isolate to replace the CU? Furthermore, would you fit a separate isolation in this instance (ie at the same time as replacing a CU)?

And I suppose final question on the matter, why don't the DNO provide some sort of isolation on the service head as standard? Actually, I think I've just answered this one in my head - because that would allow the supply to be isolated before the meter making it easier to tamper with the meter.

 

[Bobster]

If you use the search function on this forum, there are literally hundreds of threads on this subject.

Some people have the seal fairy visit, others the DNO to remove the fuse.

Edit: If you are going to pull a main fuse, disconnect all outgoing loads first, remember the live side of the fuse probably has a 400A fuse backing it. After you've pulled it take the fuse out of the carrier and insert the empty carrier (this covers any exposed parts)

If the fuse carrier looks damaged or cracked, get the DNO to do it for you.

Not sure I should be giving this advise to a trainee as it's not strictly following the rules.

To be fair, it applies to pulling any fuse, try and remove the load first.

 

[hightower]

If you use the search function on this forum, there are literally hundreds of threads on this subject.

Some people have the seal fairy visit, others the DNO to remove the fuse.

You are 100% correct, my apologies - I should know better working in IT as well..... Just done a search and overwhelmed with thread count.

 

[Bobster]

You are 100% correct, my apologies - I should know better working in IT as well..... Just done a search and overwhelmed with thread count.

I've added a note to my post.

 

[hightower]

I've added a note to my post.

Yep - wasn't after advice as such, not going to lick my fingers and give it a try tonight. Just one of those types of questions that arises for everyone I suppose.

 

[D00DY_T00DY]

I'm now reading "Student's Guide to the IET Wiring Regs" and it's pretty good. But I'm on the point of responsibility and such. It states that the service head fuse should only be removed by the DNO, which got me wondering what people do to isolate the supply when they replace a consumer unit?

They go on to say it's quite good practice to fit an isolating switch between meter and consumer unit for this purpose, but if there isn't one fitted how do you isolate to replace the CU? Furthermore, would you fit a separate isolation in this instance (ie at the same time as replacing a CU)?

And I suppose final question on the matter, why don't the DNO provide some sort of isolation on the service head as standard? Actually, I think I've just answered this one in my head - because that would allow the supply to be isolated before the meter making it easier to tamper with the meter.

Some do have a double pole switch installed with the words "only to be used by a competent person(s)" some don't.. I haven't seen one
And before you had to call the dno to test your CU.. However most people turned everything off and all that was tested was the tails and then the dno or the engineer testing it would take responsibility because he turned the power back on