Switched Neutral On Tt ?

[Jcspark]

Could someone just confirm this ?

As per my previous posts, Ive made up a 400amp isolator with 5 powerlok sockets attached to the bottom.

Its a tt supply that we will provide the earth rod for. The client will fit an RCD to the install so as to meet disconnection times.

Its dawned on me (2days before the job!) that perhaps the Neutral should be switched also as its TT. The manufacturer does not do a 400a fused TP and Switched N isolator.

The neutral bar inside is disconnect able , by spanner via a small link.

Thoughts please ?

reply 

This is just a post to get my count up so to post pics!

Hi

Sorry trying to get post count up so I can post pics...but not happening.

 

[Andy™]

Ask someone competent to do the job.

 

[Blue Duck]

Just don't whatever you do ask Andy....

Oh wait.....

 

[Andy™]

Just don't whatever you do ask Andy....

Oh wait.....

have you read this other thread?

basically

'ive been asked to install 400a powerlocks. what do i do, bearing in mind ive never touched anything more than domestic single phase. and its too late to get someone else because ive already said i can do it'

 

[Jcspark]

I am competent, it just not an areas that Im that familiar with. Like all good business owners its about using the correct people and being properly prepared. Do you think all bosses would be competent in the practical/design side of every job they undertake ? 

Anyway Ive confirmed today that indeed we need 4 pole isolation. A slight oversight on my part, That aside we have pretty much got the design nailed. We are omitting an RCD but have a signed declaration from the client that this is a deviation and that they are installing RCD protection on their part of the install.

We have had one rod down so far at 1m and readings of 60Ohms on soft ground so confident of a decent Ra in the end up, although still not meeting disconnection times.

 

[Andy™]

you may be competent at what you normally do, but you are not competent at what you are trying to do now

 

[Jcspark]

I like a challenge and Im not a "can't do" type of person Ill fire a few pics up see what you think if anythings looks bad then I welcome the advice.









We are hoping to source a 4 pole fused isolator today which should fit straight in ( Same manufacturer ) 

 

[Andy™]

what material is the base made from? hope its not magnetic (did you buy it like that?)

 

[Jcspark]

Comon Andy, give me some credit , Its solid plastic. 

It was basic metal spreader plate that came with enclosure, I had to adapt something to avoid EC ....obviously.

 

[Blue Duck]

So this wasn't a can you teach me to such eggs thread....

I can understand your reasons andy. I noticed the "shall I spike the gas meter" thread has reared it's ugly head again..........

Nice bit of kit there jc what it being used for?

 

[Jcspark]

Thanks BD, its power supply for BBC temporary studio for commonwealth in Glasgow. 

As mentioned not my usual line of work so open to any criticism of the install.

 

[Blue Duck]

Good stuff

I think Andy's just trying to sort the wheat from the chaff, it's hard these days as there is so much chaff about clogging up the forum with things that are really quite basic and  quite worrying.

 

[Andy™]

well if he did build that himself, then it does look like he has done a good job of it

 

[benji]

Might need a spreader box on the top ?

 

[Sidewinder]

You could argue that if this does come under BS7671 then this is a "site built assembly", see 612.4.5 & GN3, along with cross references from there and requires all of the tests etc. associated with that.

The term "site built assembly" has now fallen into the ark, but, should be familiar with the competent.

If it is NOT a "site built assembly" under BS7671, then I would suggest that it comes under the LVD and requires certification against that with the required testing and documentation against BS EN 61439...

Otherwise a nice build on the face of it, I just hope that you have PII in case it goes wrong and kills someone, or burns a BBC mobile studio to the ground

 

[NozSpark]

Comon Andy, give me some credit , Its solid plastic. 

It was basic metal spreader plate that came with enclosure, I had to adapt something to avoid EC ....obviously.

But is that plastic just regular plastic or is it non flame propagating plastic?

 

[Sharpend]

Crikey at this rate he'll be taking a hammer to it!!

 

[NozSpark]

I only thought about that because they did a flame test on some pedastal fans on Fake Britian yesterday. ... needless to say, the flame did not go out by its self

 

[binky]

well if he did build that himself, then it does look like he has done a good job of it

it that an apology, or as near as we will ever get? :slap

 

[Andy™]

it that an apology, or as near as we will ever get? :slap

dont push your luck!