100amp Switch Fuse required or not required?

[Input]

Hi All

When upgrading a fuse board privately or commercially, if the board is right next to the meter (or within a distance less than 3m's) is a 100amp switch fuse required?

I've seen them installed when CU's are installed more than 3m's away.

But generally most electricians I've seen just upgrade the board and do not install a switch fuse after the meter if within close proximity.

Are they wrong in not installing one?

Does this come up as a C3 on the EICR? And if upgrading many CU's for council should Electricians be notifying them that the Switch's are required?

If they don't spec it should the sparks contractor be telling them they must have one?

 

[Deleted member 26818]

No, the Regs. allow for protection to be placed within 3m.
An isolator would be useful to enable replacing the CU at a later date.

 

[buzzlightyear]

answer to no, are you thinking 100amp isolator.

 

[Pete999]

Hi All

When upgrading a fuse board privately or commercially, if the board is right next to the meter (or within a distance less than 3m's) is a 100amp switch fuse required?

I've seen them installed when CU's are installed more than 3m's away.

But generally most electricians I've seen just upgrade the board and do not install a switch fuse after the meter if within close proximity.

Are they wrong in not installing one?

Does this come up as a C3 on the EICR? And if upgrading many CU's for council should Electricians be notifying them that the Switch's are required?

If they don't spec it should the sparks contractor be telling them they must have one?

Are you an Electrician?

 

[Ian1981]

It's usually the DNO who specifies a fused isolator if the tails are greater than 3 meters as they will only protect their equipment upto 3 meters.

 

[davesparks]

I smell a rat here, the OP feigns ignorance yet refers to the 3metres rule as if he is not ignorant of it, and then specifies the situation of CU replacements for a council.

OP are you involved in specifying council house CU replacements by any chance?

 

[buzzlightyear]

a rat, me thinks has well .some body has been on this forum from Hornchurch?

 

[Pete999]

a rat, me thinks has well .some body been on this forum from Hornchurch?

As well.

 

[buzzlightyear]

But generally most electricians I've seen just upgrade the board and do not install a switch fuse after the meter if within close proximity.

come on Watson the games afoot!

 

[Input]

not a rat - human here! I'm an new electrician and work with electricians some have advised about the 3m rule and to have a 100 amp switch fuse if tails are longer, and some also say that an isolator just after the meter is required.

I'm just slightly confused - I've been working on council properties and the main sparks have not been installing an isolator of some kind after the meter when the board is at the origin.

Just trying to clarify

 

[Billsays]

Fine place Hornchurch.
However the op does seem a bit like he is fishing!
Local councils and housing associations do sometimes spec for an isolator after the meter if your changing the board .....and EDF want you to install an isolator BEFORE the meter when doing new laterals.

 

[Input]

yes fishing for answers not a witch hunt crikey!

in terms of the regs is an isolator required? after the meter and before the board

 

[davesparks]

not a rat - human here! I'm an new electrician and work with electricians some have advised about the 3m rule and to have a 100 amp switch fuse if tails are longer, and some also say that an isolator just after the meter is required.

I'm just slightly confused - I've been working on council properties and the main sparks have not been installing an isolator of some kind after the meter when the board is at the origin.

Just trying to clarify

Have you looked in your regulations book?
I'm surprised that this didn't come up during your apprenticeship but the DNOs generally stipulate that a maximum of 3metres of cable may be connected to their supply before a protective device is installed.
Note that this is a 3metre length of cable between the cutout and CU, not a 3metre physical distance between cutout and CU.

 

[Billsays]

Less than 3M no. But it can be an Employers requirement. I.e. In their specification.

 

[buzzlightyear]

ok ,you tell us!

 

[Input]

Many thanks

 

[davesparks]

yes fishing for answers not a witch hunt crikey!

in terms of the regs is an isolator required? after the meter and before the board

Your opening post gave the distinct impression that you were hiding something and fishing for someone to do your job for you.

When writing a post take time to be clear about what you are asking, and try to proof read it from the point of view of a person who doesn't know you and knows nothing of your situation.

An installation should have a main switch which isolates all live conductors (except some TP installs where the neutral need not be switched) this can be incorporated in a CU or DP or it can be a separate item.

 

[davesparks]

yes fishing for answers not a witch hunt crikey!

in terms of the regs is an isolator required? after the meter and before the board

Your opening post gave the distinct impression that you were hiding something and fishing for someone to do your job for you.

When writing a post take time to be clear about what you are asking, and try to proof read it from the point of view of a person who doesn't know you and knows nothing of your situation.

An installation should have a main switch which isolates all live conductors (except some TP installs where the neutral need not be switched) this can be incorporated in a CU or DP or it can be a separate item.

 

[Input]

Apologies, it's just i was working on council properties previously with another company and they always installed

Wylex 100A DP Supply Isolator

but now with another company also working on kitchen rewires and CU upgrades but we are not installing the above. And when mentioned they said due to them not being spec'd by the client so was just wondering whether these are a requirement so the installation has a means of isolation other than removing the main fuse...

 

[westward10]

Not liking it again Dave