Switch fuse for tt submain

[Bellendian]

Hi,

My solution in this scenario has always been to get a Lewden switch fuse unit, and replace the 100A main switch with a wylex s-type RCD to achieve earth fault protection.
With this new requirement in the 18th, am I no longer going to be able to do this?
If not, does anyone know of an off the peg solution?

Cheers

 

[davesparks]

Which new requirement of the 18th?

 

[suffolkspark]

Yes.... Fit a lewden rcd?

Part number is 100/100/2/S

 

[MDJ]

I understand your thinking, but lets look again at the question, Switch fuse for a TT submain? Based on your question I would say any 2 pole if single phase or 3 pole if 3 phase, would you like to re submit your question?

 

[Strima]

I understand your thinking, but lets look again at the question, Switch fuse for a TT submain? Based on your question I would say any 2 pole if single phase or 3 pole if 3 phase, would you like to re submit your question?

Wouldn't that be a four pole for three phase?

 

[MDJ]

Wouldn't that be a four pole for three phase?

No never be able to split the Neutral on three phase lol, an example, if a 4 pole contactor fails, and it has been known, you co

Wouldn't that be a four pole for three phase?

If it has a Neutral yes, many machines have not though

 

[Strima]

No never be able to split the Neutral on three phase lol, an example, if a 4 pole contactor fails, and it has been known, you co

If it has a Neutral yes, many machines have not though

As this is for a distribution circuit on a TT system then four pole would comply whereas a three pole wouldn't as we should isolate all live conductors on a TT system.

Ideally all machines should be shut down and all loads should be removed before disconnecting the supply however I would guess this is domestic so a bit of a mute point.

Haven't seen many decent size machines in a domestic setting unless she's been single for a while...

 

[Deleted member 26818]

I think the OP is talking about installing the Lewden RCD into a Wylex enclosure.
Which would mean the type testing would be invalid and the unit would no longer comply with the required standard.

 

[Nigel]

FDB Electrical will build an RCD to any specification you want.

Enclosed Units | FDB Online - https://www.fdbonline.co.uk/collections/enclosed-units

 

[suffolkspark]

I think the OP is talking about installing the Lewden RCD into a Wylex enclosure.
Which would mean the type testing would be invalid and the unit would no longer comply with the required standard.

Na hes on about fitting a lewden off the shelf switch fuse and putting a wylex typeS rcd in it.... Which he doesnt need to do as lewden make a typeS rcd, perhaps he just didnt know

 

[Bellendian]

Yep spot on suffolk. Just got to persuade wholesalers to stock the Lewden RCD now. Should do, there are loads of TT supplies round here so its not like I'm the only one thats going to need it...
Cheers

 

[suffolkspark]

Denmans have them on the shelf mate, easy to pick up online too

 

[Octopus]

Am i being a bit thick here but what about over current protection on tbe sumain?

 

[suffolkspark]

The fuse....

 

[Octopus]

Of course

Maybe Lewden should make such a product for the market.... Not exactly difficult ....