Looking for opinions

[Battlecrease]

Hi all,
Dont know if this has been covered in the past but I cant find it if it has . I have recently received an email from npower informing me that if I require an 80amp MCB installing in place of a 100amp isolator that they are not allowed to do this anymore due to amendment 3 but they can install 100amp isolators from scratch now correct me if I am wrong but I do not see any differential between SWITCH /RCD / MCB under amendment 3 definition they are all classed as switch gear and if npower cannot do it then no-one else is allowed to do it how the hell does the job get done?
Furthermore I also deal with Quartz electric who carry out a similar role around the Merseyside area and they dont have a problem with installing MCB OR RCD but are not allowed to work outside their jurisdiction So how the hell can this situation arise at different DNOs ? interpreting amendment 3 differently, If you have had a similar experience let me know or if it is dealt with differently around the country let me know also Im sure this is just the tip of the ice berg.

 

[davesparks]

Re: Looking for opions

Why would you want an 80A MCB?

 

[YoungScud]

Re: Looking for opions

Distribution systems are excluded from the scope of the Regs, so I'm not sure what npower are on about.

 

[Spoon]

Re: Looking for opions

I'm with dave on this and curious as to why the OP wants a 80A MCB fitted.

 

[Battlecrease]

Re: Looking for opions

Sorry for the confusion I have just repeated the email from npower that if I required an 80amp MCB they will no longer fit one?
Problem is new sub-board ,long run for tails buried in fabric of the building and tails require RCD protection ,Easiest option would be to RCD protect tails, second option surface mount tails so no need to protect tails either way I cant see how they can differentiate between the 3 devices they are all switchgear, or are they?

 

[DPG]

Re: Looking for opions

Are you sure you mean an MCB and not a fused isolator? What is the reason for an MCB being required? Daz

 

[davesparks]

Re: Looking for opions

Sorry for the confusion I have just repeated the email from npower that if I required an 80amp MCB they will no longer fit one?
Problem is new sub-board ,long run for tails buried in fabric of the building and tails require RCD protection ,Easiest option would be to RCD protect tails, second option surface mount tails so no need to protect tails either way I cant see how they can differentiate between the 3 devices they are all switchgear, or are they?

Protecting the tails with an RCD is not normally a viable option anyway so that point is largely irrelevant.
My point about the MCB is that you wouldn't ordinarily want an MCB protecting the distribution circuit which feeds the CU as an HRC fuse will give a far better degree of discrimination.

 

[Battlecrease]

Right I do not require , want or have requested an 80amp MCB I am just relating an email I received recently from npower and am curious wether anybody else has come across this as I am struggling to understand how they can differentiate between switch/MCB/RCD as far as I am concerned it is all classed as switch gear and secondly how different DNOs manage to interprate things differently

 

[Spoon]

Right I do not require , want or have requested an 80amp MCB I am just relating an email I received recently from npower and am curious wether anybody else has come across this as I am struggling to understand how they can differentiate between switch/MCB/RCD as far as I am concerned it is all classed as switch gear and secondly how different DNOs manage to interprate things differently

As youngstud has mentioned in post #3, "Distribution systems are excluded from the scope of the Regs"

 

[Battlecrease]

Cheers Spoon, I was thinking the same but cant understand why npower would volunteer themselves to be included in the regs at the cost of losing work and money.