Lighting circuit powered from 15A ring main

[cormier]

I have a need to install some wall lights in a kitchen and for various reasons cannot access the 5A radial lighting circuit. Is it permissible to take a spur from the 15A ring main (which I can access) provided that it has a 5A fuse and switch incorporated. There will be 6 x 20W low voltage tungsten and 6 x 20W slimline fluorescent lamps connected along the spur. Also can I assume that the total current drawn will be approximately 1A (I have read somewhere that fluorescent lamps must be over-rated when doing this sum). Many thanks for your help.

 

[Scoby_Beasley]

No expert but could you clarify your 15A ring? Should be 30/32A.
15 sounds like a radial.

 

[Inspector]

No - Not permissible

... but it will work

 

[ban-all-sheds]

Why is it not permissible?

 

[unphased_spark]

Ban you beat me to it , spur through a FCU WITH 2.5mm then 1.5mm the other side should be fine making sure the correct fuse is in place 6amp

 

[plugwash]

unphased_spark it is normal parctice to use a 3A fuse if you are running a single light

and 6A plug sized fuses don't exist afaict

 

[Inspector]

Not permissible because it is possible to inadvertently fail to isolate during maintenance of the spur supplied lights. ie you isolate the kitchen lighting circuit but the lights off the spur remain live. This is bad practice.

 

[Big_Spark]

Not permissible because it is possible to inadvertently fail to isolate during maintenance of the spur supplied lights. ie you isolate the kitchen lighting circuit but the lights off the spur remain live. This is bad practice.

You and I, the NICEIC, the ECA and most Electricians in the UK will disagree on that point Inspector.

There is nothing wrong with the circuit as explained, it is not bad design at all, and if you have an NICEIC Technical Handbook available you will see it is perfectly acceptable so long as the spur is fused correctly.

I would guestimate that 80% of all under-unit lighting in kitchens is powered using this method to prevent vertical cable runs on kitchen walls..for obvious reasons.

 

[AdamW]

I would guestimate that 80% of all under-unit lighting in kitchens is powered using this method to prevent vertical cable runs on kitchen walls..for obvious reasons.

Ah, but then people are EXPECTING that... however, this post is about wall lights. Every house I have ever been in with wall lights in the living room had the lights wired in to wall switches on the lighting circuit. Must say I have never seen them in kitchens though.

To me it does sound like bad design to wire lights in to FCU's on the ring/radial... although from what I have learned I wouldn't think it would contravene regs. I will sit right in between FWL and Inspector on this one

From what Inspector says, it sounds like he is assuming there will be a switch BETWEEN THE FCU AND THE LIGHTS. You would know if your lights aren't isolated by the way they are currently emitting light. Is it allowable to do this? I would think not as then it would easily be mistaken for a lighting circuit switch (take it off the wall: one T&E in, one T&E out).

Is it not necessary to have the FCU in a visible location? In other words would it perhaps be worth the hassle of accessing your lighting circuit to avoid having a big ugly switch in the middle of your soon-to-be very bright kitchen?

 

[securespark]

Adam, mate, I shall call you Paddy Ashdown due to your prolonged fence-sitting!! May you get a sore ar*e!!!

 

[Big_Spark]

Ah, but then people are EXPECTING that... however, this post is about wall lights. Every house I have ever been in with wall lights in the living room had the lights wired in to wall switches on the lighting circuit. Must say I have never seen them in kitchens though.

I think you will find that when he re-posts these will turn out to be undercupboard, and possibly in-cupboard lights..look at their power ratings..dead give-away.

To me it does sound like bad design to wire lights in to FCU's on the ring/radial... although from what I have learned I wouldn't think it would contravene regs. I will sit right in between FWL and Inspector on this one

Nothing link having an opinion is there

From what Inspector says, it sounds like he is assuming there will be a switch BETWEEN THE FCU AND THE LIGHTS. You would know if your lights aren't isolated by the way they are currently emitting light. Is it allowable to do this? I would think not as then it would easily be mistaken for a lighting circuit switch (take it off the wall: one T&E in, one T&E out).

Whilst it is not usual to install an additional light-switch, it is not uncommon either, it will depend on the actual set-up. But there is nothin bad in the design or against the Regs in doing this.

Is it not necessary to have the FCU in a visible location? In other words would it perhaps be worth the hassle of accessing your lighting circuit to avoid having a big ugly switch in the middle of your soon-to-be very bright kitchen?

Like your sockets and Spurs for other purposes such as feeding unswitched, under-unit sockets for fridges and freezers?

 

[kendor]

Just to add on an above comment regarding lights not being isolated, also NEVER assume a circuit is isolated just because a light isn't on (the fitting/lamp may be faulty) always test a circuit with a reliable instrument to make sure it is dead (something an electrician will do as a matter of course but should be common sense for anyone attempting to work on electrics).

 

[il78]

I always miss the good arguments...

 

[unphased_spark]

Plug,

Apologies, actually mean't 3amp for the FCU but typing quicker than thinking and hit 6 thinking still thinking > light circuit........ Cheers

 

[Big_Spark]

I always miss the good arguments...

Well you usually start them