dual rcd board problems

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poheZ

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I have had two board changes this week, both have had a borrowed neutral on the landing light (2way)! Is this a problem anyone else has found alot?

 

Mr Sworld

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It's a very common problem and as 17th recommends that lighting circuits on different floors are on separate rcd's/rcbo's you are going to see it a lot more!

 
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yes, i've changed loads and i'd guess about 75% have borrowed neutrals, now you try telling customer of the need to sort this out, you may as well slip yer striped jersey and swag bag on, rcbo's wont help as both will trip on switching, 17th ed should have simply been an amendment to the 16th and soley concerned bathrooms/rooms of higher risk and all types of external wiring, job done, my money is on a revised issue coming very shortly and not before time

 
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Most customers won't be interested, they will say it worked fine before you changed board. I find when quoting for board changes if you say about wiring faults. They don't understand that if you have neutral to earth faults it will trip out Rcd's. You have either got to allow for this in your price or quote per hour to sort out faults. Either way you may not get job.

Batty

 

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yes, i've changed loads and i'd guess about 75% have borrowed neutrals, now you try telling customer of the need to sort this out, you may as well slip yer striped jersey and swag bag on, rcbo's wont help as both will trip on switching, 17th ed should have simply been an amendment to the 16th and soley concerned bathrooms/rooms of higher risk and all types of external wiring, job done, my money is on a revised issue coming very shortly and not before time
No chance!!!

The biggest problem with a shared neutral is nothing to do with RCDs RCBOs tripping...

Its when some poor spark (or diy Bob!) is working on the upstairs light circuit isolated at CU..

& someone switches on light supplied from downstairs circuit...

and gets a shock from wires now energised that should be dead!!!!

(hopefully not a fatal shock! :( )

The fact that the OLD cu could not identify NON compliance with

reg 314.4 17th {This is then bit about ALL circuits being separate from other circuits!!!}

this was reg 314-01-04 16th in Brown Book AND Yellow book 1992!!!

The fact that we sparks have NOT been adhering to guidance that goes back 16years+...

then that is NOUGHT to do with 17th edition me thinks!!!!

just historical bad practice!!

 

Apache

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OK - how do you wire the lighting on the stairs? Should the neutral for both switches come from the same lighting circuit (upstairs?)

 

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OK - how do you wire the lighting on the stairs? Should the neutral for both switches come from the same lighting circuit (upstairs?)
wherever the particular bulb gets its live from..

it must get its neutral from the same circuit!!!

for some weird reason people think is OK to cross lighting circuit wiring..

but if thats OK then why not swap socket outlet wiring as well???

Just wire your upstairs & downstairs lights as norm..

and run 3-core+e between any switches you need as two way!!

somewhere, cant remember at the moment, but it advises to have separate circuits suppling landing & hall..

such that if one circuit fails you still have light at either top of bottom of stairs! ;)

 

sirsparkabit

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wherever the particular bulb gets its live from..it must get its neutral from the same circuit!!!

for some weird reason people think is OK to cross lighting circuit wiring..

but if thats OK then why not swap socket outlet wiring as well???

Just wire your upstairs & downstairs lights as norm..

and run 3-core+e between any switches you need as two way!!

somewhere, cant remember at the moment, but it advises to have separate circuits suppling landing & hall..

such that if one circuit fails you still have light at either top of bottom of stairs! ;)
I hope not specs i always wire my landing light into my downstair circuit that does the hallway light.Blushing] :)

I read a long time ago this was the way to do it ,specifically to avoid the dangerous borrowed neutral situation.

I think i might be out of date Please don't use the birch twigs on me:_|Pray

 

daryl631

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I am doing board change at the mo all lights in house on one circuit owner would not rewire lights,also wiring double extension in same house so separated upstairs and down on new circuits best could be done with this one.

 

daryl631

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I am doing board change at the mo all lights in house on one circuit owner would not rewire lights,also wiring double extension in same house so separated upstairs and down on new circuits best could be done with this one.
forgot to add new extensionBlushing
 

daryl631

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morning got day off waiting for plasterers to finish yawn,doing electrics part time at the mo trying to build up bussiness full time job as well need to get the money in before jumping ship on job.Pray

 

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I hope not specs i always wire my landing light into my downstair circuit that does the hallway light.Blushing] :) I read a long time ago this was the way to do it ,specifically to avoid the dangerous borrowed neutral situation.

I think i might be out of date Please don't use the birch twigs on me:_|Pray
ok boys pull up a chair... its story time... :D

I will get the story book out........

when we last left our hero he was stuck in the swamp of exported earth....

this weeks book is...

Domestic Electrical Installation Guide, ISBN 0-9548791-1-2 {this is an NICEIC publication 2005}

let us continue... bottom of page 101..

Chapter 8.12 Lighting circuits - general.Lighting in household premises should be served by one or more designated radial final circuits, according to the size and layout of the property. Where practicable more than one circuit should be provided, even in small premises, so as to avoid the loss of all lighting should one circuit be disconnected due to the operations of its circuit protective device.
{turns the page.. page 102! :) }

It is desirable for areas such as a hallway and stairs to be served by separate circuits so that some light for the stairs is still available should one of the circuits be disconnected..
obviously this is just guidance..

but I suppose it does meet the requirement of 314.1 (iii) pg 39 the big red book quite well???

314.1 Every installation shall be divided into circuits, as necessary to;(iii) take account of danger that may arise from the failure of a single circuit such as a lighting circuit.
:) :)

now then......

where are those birch twigs!!! ]:)

ADMIN!! you seen who's borrowing the BIRCH TWIGS? ?:|

If they are in the back of Theory's cave .... tell him we need them back NOW! X(

If its Slipshod........ we can wait till later when he's finnished... Blushing

If they are left in Steptoe's yard????? :_| :_|

there a gonna!!!

we shall just have to wait until we can grow some more in the forum garden!

Guiness Drink:p

 

Admin1

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Oh, and Congratulations on passing your 2,000 mark, Sir. Applaud Smiley

 

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Oh, and Congratulations on passing your 2,000 mark, Sir. Applaud Smiley
oh eh... 2000+

its a good job you didn't have a Millennium bug in the forum.. Y2K compliant eh what??? :^O

It would of been a bit embarrassing if traffic lights had stopped..

hospital monitoring equipment failed

air traffic control systems crashed........???

hang on there WAS a problem the other day with an air-traffic control computer somewhere....?

Hope I didn't cause it........ Blushing 'Y2K' did exist!!

just like KME taking my sole at '666' ]:) ] :) ]:)

ohhhh this is getting scary! :eek: :O:O:O:O

 
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