Advice and an opinion

[mercurystar999]

2 gang lightswitch at bottom of stairs on a new rewired property has three core from upstairs in it, plus switch wire from downstairs light. My opinion is that it is fine as you need to be competent to even take the switch off. Another mate of mine is saying it has 2 supplies and contravenes regs.

Opinions please

 

[green-hornet]

the 3 core from the upstairs switch is the strappers for two way switching. There will be no other circuit in the switch. There can be more than one circuit in a switch and this does not go against any regulations, all electricians will know the danger and do safe isolation.

If the supply is three phase then the switching must be labelled to warn of any voltage above 230 which you would have if more than one phase is brought into the switch.

 

[a1spark]

Hi GH. The 3-core from upstairs will most likely be on the upstairs circuit therefore there will be two circuits in the downstairs switch, It is a requirement to install a warning notice ..usually inside the switch to notify of the situation..similar to the requirement for a 400v situation.

 

[green-hornet]

Hi GH. The 3-core from upstairs will most likely be on the upstairs circuit therefore there will be two circuits in the downstairs switch, It is a requirement to install a warning notice ..usually inside the switch to notify of the situation..similar to the requirement for a 400v situation.

If the switch wire is in the downstairs switch with a three core to the next landing then it would be safe to say its one circuit from the bottom of the stairs, unless at the top of the stairs there is another switch wire.

In which case the bottom switch will have one circuit, and the upstairs switch will have two, however because it is domestic and from the same phase there will always only be 230 volts at the switch.

Which is why electricians will be aware of this and isolate accordingly, there is only a requirement to label when more than one phase is taken to any switch which would be above 230 volts.

 

[a1spark]

G.H. I see now how you are reading it but i see it as the three core running from the downstairs two-way on the 2-gang then up to connect with the Live & s/L at the ist floor landing .for the landing light. Then also at the downstairs 2-gang the Live & s/L from the ground floor hall light { which the Op describes as the switch wire]..... This is standard wiring in Hall & landing switch set up on 2-gang plates in domestics.... you theory is ,of course ,also plausable.

On the point about warning of more than one circuit in the switch and therefore in an enclosure ,I was referencing 537.2.1.3.

 

[green-hornet]

I think given the narrative (description) we are both right.

We do indeed at least need to know what is in the second switch on the landing.

 

[NozSpark]

Doesn't the reg say something like..

any accessory that is supplied from multiple circuits with seperate points of isolation must have a warning label stating "........."

IMO in a normal house then isn't the Isolation switch the single point of isolation and not the MCB!

 

[Andy™]

2 gang lightswitch at bottom of stairs on a new rewired property has three core from upstairs in it, plus switch wire from downstairs light. My opinion is that it is fine as you need to be competent to even take the switch off. Another mate of mine is saying it has 2 supplies and contravenes regs.Opinions please

but its only 1 supply. unless you have 2x service heads and one side of switch from each. and nothing wrong with muliple circuits either. very common in commercial/industrial

 

[mercurystar999]

Sorry if i have confused.

The 2 gang switch switches the downstairs light which is fed from downstairs circuit and also has just a three core and earth which switches the upstairs light fed from the upstairs circuit.

 

[mercurystar999]

It really is just a question as to whether it is ok to have 2 circuits in one switch.

 

[green-hornet]

Then it is two seperate circuits and is normal practice, there should be no issue about any safety problems because the wiring described is fully acceptable. There would be no requirement to label if both circuits are from the same phase.

 

[batty]

It really is just a question as to whether it is ok to have 2 circuits in one switch.

Has been done like this for years and really you should not be touching electrics unless you are competant. Any assessory you buy will have this stated on it unless you buy it from a wholesaler and then you should be qualified anyway.

 

[mercurystar999]

Sorry i should of been clearer. I totally agree with you and have wired this way for years but i was picked up on it by an old timer that deemed it necessary for me to wire the upstairs landing light off the downstairs circuit so as not to have 2 circuits in the downstairs light switch. He also always puts it down as a deviation when doing pir's.

I was fed up of arguing so just changed it as the place was empty anyway.

 

[batty]

Sorry i should of been clearer. I totally agree with you and have wired this way for years but i was picked up on it by an old timer that deemed it necessary for me to wire the upstairs landing light off the downstairs circuit so as not to have 2 circuits in the downstairs light switch. He also always puts it down as a deviation when doing pir's. I was fed up of arguing so just changed it as the place was empty anyway.

Don't worry he's probably a borrowed neutral or live believer.

 

[initforthemoney]

Another mate of mine is saying it has 2 supplies and contravenes regs.

Wrong....

 

[ADS]

Sorry i should of been clearer. I totally agree with you and have wired this way for years but i was picked up on it by an old timer that deemed it necessary for me to wire the upstairs landing light off the downstairs circuit so as not to have 2 circuits in the downstairs light switch. He also always puts it down as a deviation when doing pir's. I was fed up of arguing so just changed it as the place was empty anyway.

Hi mate,

How exactly did you change it?

If you have changed it so that the downstairs circuit now feeds the landing light, then the landing light will have it's line from downstairs and it's neutral from upstairs, that does contravene the regs.

You were better off leaving it as it was, unless you're running a neutral from downstairs as well.

 

[mercurystar999]

Hi mate,How exactly did you change it?

If you have changed it so that the downstairs circuit now feeds the landing light, then the landing light will have it's line from downstairs and it's neutral from upstairs, that does contravene the regs.

You were better off leaving it as it was, unless you're running a neutral from downstairs as well.

Why would it?

Just took a 1.0mm twin and earth to the upstairs landing light from downstairs and disconnected the supply to the upstairs light.

 

[Evans Electric]

Couple of months ago we did a 12 gang switch with 6 circuits in it . Put the 400v warning on but to be honest the number of circuits is down to safe isolation . If I took a 2 gang switch off I would be checking to see if there were 2 circuits , its quite common after all .

Doubtless I will be shot down in flames .

 

[batty]

I would think people would be more at risk having up and down on one circuit ie. landing light on downstairs circuit due to fact they would think its on upstairs circuit.

 

[ADS]

Why would it?Just took a 1.0mm twin and earth to the upstairs landing light from downstairs and disconnected the supply to the upstairs light.

Hi,

That's why I asked how you'd changed it

If you've run a 1.0mm up, then you've took the neutral as well, so not a problem with borrowed neutral.

Where you would come unstuck in that situation is if (as I've seen many a time), the landing light switch upstairs was also a two gang, normally switching the bathroom light as well. This would mean you'd have two circuits at this switch instead.

What would you do then?

To be honest, you could have a three gang switch and three different circuits in it and it still complies.

It's up to the 'competent' person working on the installation to confirm 'safe-isolation'.