This discussion is locked.

You cannot post a reply to this discussion. If you have a question start a new discussion

Wylex 100A dp isolators in plastic enclosures.

Just wondered why these are not classed as "similar switchgear" to consumer units etc which are supposed to be in

non flammable enclosures in domestics.

Regards,Hz

Parents

0 gkenyon over 5 years ago

Alcomax:

If you consider the tails to the consumers equipment in TT as a circuit- I assume you do from earlier comments- that circuit has double or re-inforced insulation as the "sole protective measure" [ dictated by 531.3.5.3.2.201] and 412.1.2 tells us, in general terms, this measure shall not be used to any circuit with an earthing contact. So you cannot have an earthing contact for termination.

There is a particular error in the logic here.

412.1.2 is talking about where the whole installation (yellow highlight) is double insulation, it can only be provided where there is adequate supervision in place (green highlight), i.e. certainly nothing to do with an up-front RCD for a dwelling!

The part you are quoting about the earthing contact, is about socket-outlets with earthing contacts not being used for the circuit. It can be used for parts of equipment, which is what we are talking about here ... don't forget, sheathed cables (e.g. T&E) are considered to have "double insulation".

412.1.2 Where this protective measure is to be used as the sole protective measure (i.e. where a whole
installation or circuit is intended to consist entirely of equipment with double insulation or reinforced insulation),
it shall be verified that effective measures, for example by adequate supervision, are in place so that no change can
be made that would impair the effectiveness of the protective measure. Therefore this protective measure shall not
be applied to any circuit that includes, for example, a socket-outlet with an earthing contact, luminaire supporting

coupler (LSC), device for connecting a luminaire (DCL) or cable coupler, or where a user may change items of

equipment without authorization.

Conversely, if your argument regarding this Reg were to hold, the Reg would effectively preclude the double-insulated RCD enclosure from supplying an installation with BS 1363-2 or BS EN 60309-2 socket-outlets.
Cancel
Vote Up 0 Vote Down

Cancel

Reply

0 gkenyon over 5 years ago

Alcomax:

If you consider the tails to the consumers equipment in TT as a circuit- I assume you do from earlier comments- that circuit has double or re-inforced insulation as the "sole protective measure" [ dictated by 531.3.5.3.2.201] and 412.1.2 tells us, in general terms, this measure shall not be used to any circuit with an earthing contact. So you cannot have an earthing contact for termination.

There is a particular error in the logic here.

412.1.2 is talking about where the whole installation (yellow highlight) is double insulation, it can only be provided where there is adequate supervision in place (green highlight), i.e. certainly nothing to do with an up-front RCD for a dwelling!

The part you are quoting about the earthing contact, is about socket-outlets with earthing contacts not being used for the circuit. It can be used for parts of equipment, which is what we are talking about here ... don't forget, sheathed cables (e.g. T&E) are considered to have "double insulation".

412.1.2 Where this protective measure is to be used as the sole protective measure (i.e. where a whole
installation or circuit is intended to consist entirely of equipment with double insulation or reinforced insulation),
it shall be verified that effective measures, for example by adequate supervision, are in place so that no change can
be made that would impair the effectiveness of the protective measure. Therefore this protective measure shall not
be applied to any circuit that includes, for example, a socket-outlet with an earthing contact, luminaire supporting

coupler (LSC), device for connecting a luminaire (DCL) or cable coupler, or where a user may change items of

equipment without authorization.

Conversely, if your argument regarding this Reg were to hold, the Reg would effectively preclude the double-insulated RCD enclosure from supplying an installation with BS 1363-2 or BS EN 60309-2 socket-outlets.
Cancel
Vote Up 0 Vote Down

Cancel

Children

No Data

Wylex 100A dp isolators in plastic enclosures.

Community Rules & Guidelines