Examples of, anyone?

[the pict]

Can anyone give me examples of
"Use of electrical seperation to supply an individuall item of equipment",
and as above for more than one, I have read through 418.3 etc but I cannot find an example, I know that it is outside the remit of BS7671 to provide examples for everything, the book would run to several volumes, however a few examples would help
Pict

 

[BigBreakfast]

Think of selv for one as an example .

 

[the pict]

Yes in a domestic situation the shaver point is selv but it is the "provision of a SELV circuit" I should have asked what in your experience in a commercial environment are examples you have come across equipment wise and why was it seperated and how,
Pict

 

[Richard Burns]

A shaver point is not SELV it is separated but it is not ELV.

 

[the pict]

Absoulutly correct Richard, I stand corrected, I was thinking of the seperated aspect, but I really must pay more attention, more caffiene required
Pict

 

[DaveyD]

a few examples would help
Pict

Hi Pict, What about an isolating transformer in a radio/tv repair workshop.
Regards, Dave

 

[the pict]

Good one Davey, to be honest I am struggling to find any other than similar to your suggestion probably schools colleges etc, elv lighting apart
Pict

 

[stef]

Hi pict, try 110 V tranny for electrical hand tools, low voltage transformer for 12v downlighters, high/ low voltage transformers in substations, transformers for door bells, mobile phone chargers from the 90s ( not the modern ones you get today cos they aren't sepparating, really), ...

 

[StuSpiers]

Blackely units in schools.

Although they don't supply one item they are for bench sockets usually.

 

[stef]

Learned something new, had to google this Blakely unit to see what it was.

 

[RogertheBodger]

Electric arc welding set, Neon signs.

 

[ackbarthestar]

Separated circuits, as suggested by others, don't have to be SELV.

Any circuit that employs the use of a isolating transformer where there is no earth return path on the secondary side. Hand tools, pumps compressors, used in cable tunnels where there is restricted access/movement see section 706

 

[Risteard]

A shaver socket is an example of electrical separation supplying an individual item.

 

[Deleted member 26818]

To be honest, a shaver socket does not really fit the bill as an example.
A better example would be a bell circuit that uses a transformer that fits into a CU.

 

[silverfox1]

Worked on some operating theatres where the equipment was all supplied via Isolated Power Supply panels.

 

[Edd]

To be honest, a shaver socket does not really fit the bill as an example.
A better example would be a bell circuit that uses a transformer that fits into a CU.

Why do you say its not a good example? They have 2 outputs one of 230v and the other 110v, both fed from an isolating transformer, no earth conection. In my eyes its sole means of protection is electrical seperation, its not relying on selv or any other means. your bell example is using selv as its main means of protection.

 

[Deleted member 26818]

Why do you say its not a good example? They have 2 outputs one of 230v and the other 110v, both fed from an isolating transformer, no earth conection. In my eyes its sole means of protection is electrical seperation, its not relying on selv or any other means. your bell example is using selv as its main means of protection.

A shaver socket is not an individual item of equipment that is supplied via a separated source.
An item of equipment plugged into the shaver socket would be supplied by a separated source, however such an item would fall outside of the scope of BS7671.

 

[Edd]

however such an item would fall outside of the scope of BS7671.

Can you point to where please, as i have always put on Domestic EICR's that the shaver point was a form of electrical seperation. and on comersial I would use a site transformer as electrical seperation. The NIC has never told me I was wrong. But I always like it if they are

 

[Adam W]

I would have said a shaver socket is a better example than a door bell - a door bell would be SELV. Separated yes, but also ELV which wasn't asked for.
A shaver socket is probably the example they're looking for.
An isolating transformer supplying more than one item of equipment could be a site transformer.

 

[Deleted member 26818]

Both a shaver socket and a site transformer are examples of a source of electrical separated supplies.
However neither are individual items of equipment suplied by electrical separation.