bathroom circuit - expert needed!

[craigtdann]

I want to have two settings for my bathroom lights - all on or just those over the bath on.

I will put those over the bath on one circuit and the rest on another. I will have a two pole switch which switches both circuits and a single pole switch which switches just the lights over the bath.

This should work fine.

However - I would like to be able to dim the lights over the bath so I plan to use a dimmer switch instead of a single pole switch for the over the bath circuit.

Again all sounds good...however....

I'm worried that if the two pole switch is on and the dimmer is on there is effectively live on both sides of the dimmer - does this matter? will it burn out the dimmer? I'm planning on using an MK logic plus if that matters.

I know I could put the dimmer after the two pole switch so the bath lights are always controlled by the dimmer, but I would like them to always be at max brightness when all lights are on.

Any help appreciated (including other ways of doing the circuit).

Thanks

Craig.

 

[riveralt]

In my view you would be better off having two switches separately controlling the two sets of lights you want in the bathroom.

A dimmer to switch on and control the light over the bath and a single gang switch to switch on and control the rest.

You can fit a grid switch arrangement using kit like this:

http://www.tlc-direct.co.uk/Main_Index/Wiring_Accessories_Menu_Index/Grid_System/index.html
Also this work is notifiable to your Local Authority Buidling Control.

 

[EFLImpudence]

I'm worried that if the two pole switch is on and the dimmer is on there is effectively live on both sides of the dimmer - does this matter? will it burn out the dimmer? I'm planning on using an MK logic plus if that matters.

I don't see anything wrong with what you want to do.

240V at both ends of the dimmer equals 0V.

 

[ban-all-sheds]

Craig - the law requires you to do this work safely and to apply for Building Regulations approval before you start, and in that application describe how you will ensure that your work complies with P1.

Honestly - given the grasp of electrics that your questions indicate I think you'll struggle to do that.

 

[craigtdann]

Thanks for the advice, but that doesn't answer my question.

This is supposed to be a DIY message board for people to learn - I'm looking for the information so I can design the bathroom circuits before talking to electricians and the building regs people.

I'm trying to determine what's possible before I speak to people. I like to have a good idea of what I'm talking about before I enter into these conversations - not so I can do it myself, just so I can hold a reasonable level of conversation.

If the answer to all questions is to pay an expert then we might as well close the forum down and all look in the yellow pages.

Could you try and be more helpful and describe what's wrong with my question? or better still answer my question.

Thanks.

 

[EFLImpudence]

I thought I had.

What else would you like to know?

 

[craigtdann]

Thanks EFLImpudence - I thought this was probably the case, but was worried some dimmers might be intelligent PCBs which would cause a problem.

My response was aimed at ban-all-sheds. I get a bit frustrated sometimes that posters on this forum are more intent on demonstrating their superiority rather than helping numpties like me to get a grip of the basics so we can talk to electricians/plumbers etc with knowledge rather than just having to accept whatever they say.

Thanks again - much appreciated.

 

[ban-all-sheds]

Yes, of course.

Reading this:

I want to have two settings for my bathroom lights - all on or just those over the bath on.

I will put those over the bath on one circuit and the rest on another. I will have a two pole switch which switches both circuits and a single pole switch which switches just the lights over the bath.

This should work fine.

However - I would like to be able to dim the lights over the bath so I plan to use a dimmer switch instead of a single pole switch for the over the bath circuit.

Again all sounds good...however....

I'm worried that if the two pole switch is on and the dimmer is on there is effectively live on both sides of the dimmer - does this matter? will it burn out the dimmer? I'm planning on using an MK logic plus if that matters.

I know I could put the dimmer after the two pole switch so the bath lights are always controlled by the dimmer, but I would like them to always be at max brightness when all lights are on.

Any help appreciated (including other ways of doing the circuit).

it really was blindingly obvious that you planned to use a registered electrician to design and install.

I'm not trying to be superior, and there's nothing wrong with your question, per se, it's just that the fact you're asking it shows that you don't know much about what, according your your post, you intended to start fiddling with.

As for your design Q - I concur with riveralt - just have a 2-gang switch.

 

[riveralt]

Thanks for the advice, but that doesn't answer my question.

I feel insulted - since you also asked for alternatives - one of which I gave - which would have resulted in a neater finish than the one you proposed.

This is supposed to be a DIY message board for people to learn - I'm looking for the information so I can design the bathroom circuits before talking to electricians and the building regs people.

Just because it is a DIY site doesn't abrograte responsibility from the either you the OP or those responding to your question in implementing important elements of the law. Whether you choose to take the legal advice as well as the electrical advice is up to you.

I'm trying to determine what's possible before I speak to people. I like to have a good idea of what I'm talking about before I enter into these conversations - not so I can do it myself, just so I can hold a reasonable level of conversation.

You appear to have been doing up your bathroom for over 5 months - don't you think circuit design should have been one of the first things you should have considered. By the way if you intend to get a registered electrician in then they will design the circuit not you!

If the answer to all questions is to pay an expert then we might as well close the forum down and all look in the yellow pages.

I gave you my advice free - I have not charged you.

Could you try and be more helpful and describe what's wrong with my question? or better still answer my question.

I have done - but now wish I hadn't bothered.

 

[craigtdann]

riveralt - sorry - my reply was not in any way aimed at you - I apologise if I caused any offence - this was certainly not my intention - your suggestion is fine - however I wanted to be able to flick all lights on with one switch - this wouldn't be that easy with a dimmer in a grid with a switch for the other lights.

Although I don't agree that the lighting circuit would be one of first things you'd do in a bathroom?!?

Also I don't agree that the electrician should design the circuit - that stops be being a DIYer! I'm interested in what is possible and would like him/her to explain why I can't have what I want (see below for where frustration comes from).

Thanks again - I didn't mean to cause offence

Ban-all-sheds - apologies to you as well (I guess I was having a bad morning). It's just I've seen several posts on this forum in the past (not necessarily my own threads) where a novice is made to feel inferior and is just told to speak to an electrician/plumber/authority without being told the answer to their question. Giving this kind of advice is fine and is correct, but I think it's better to answer the question as well - I probably mis-read this was another of those occasions.

BTW my father, father-in-law and brother-in-law are all qualified electricians (40, 40 and 15 years experience respectively), but they always tell me what they think I should do and not what is possible (i.e you'd dont want a dimmer) - this is a subtle difference which I find frustrating - it obviously boiled over!

Thanks for taking the time to help though and apologies to you and riveralt again.

I will try not to project my frustrations into the forum in future!