smoke detection/rcbo yes or no

[richy3333]

Your last comment is not correct, I have taken the comments from the latest edition of BS7671 that was only bought from the IET about a month ago and the definition does not appear to have changed.

The issue with the lighting circuit should really be determined by the size of the bathroom because if the ceiling height is less than 2.25m or the bottom of the luminaire is below 2.25m then Reg 701.411.3.3 must be adhered to that requires the lighting circuit to be RCD protected in accordance with Reg 415.1 which requires the RCD to have a 30mA rating.

Now as BS5839-6 clearly indicates that smoke/heat detectors should not be on an RCD rated at 30mA such a circuit should not be used.

The problem this introduces is that many domestic bathrooms in the UK do not have ceilings that allow for the bottom of the lights to be greater than 2.25m (7ft 4") from the floor. Clearly many do, but you would need to be sure first to ensure full compliance with both sets of regulations. My personal thought, and clearly others will see it as they wish and that is fine, that to ensure full compliance regardless if the snoke/heats are on their own circuit then you are on safe ground.

Just wondering Outspoken:

Why are you suddenly such an expert on domestics when by your own admittance you hate 'them' and don't do 'them'?

Why did you only buy the BGB last month when the Regs changed last year? I presume the update doesn't apply to you?

I don't understand why you are waffling on about bathrooms and smokes? What relevance is this to the discussion? How many smokes do you see in the bathrooms of average houses? I guess you must live in a mansion, being super-paid as an industrial spark

 

[stuartcourt]

Jesus ****ing wept Im going out

 

[Outspoken]

Just wondering Outspoken:

Why are you suddenly such an expert on domestics when by your own admittance you hate 'them' and don't do 'them'?

Why did you only buy the BGB last month when the Regs changed last year? I presume the update doesn't apply to you?

I don't understand why you are waffling on about bathrooms and smokes? What relevance is this to the discussion? How many smokes do you see in the bathrooms of average houses? I guess you must live in a mansion, being super-paid as an industrial spark

Bit touchy aren't you, Jesus Christ chap, you want to calm down or you'll have a heart attack. I bought a new regs book about a month ago because the last one was literally rained on when I left it on the roof of my car so I replaced it...is that acceptable to you ???

As for the experts on Domestic, I can bloody well read the regs book you know and have enough knowledge and experience to be able to understand what it and other regulations say.

Perhaps you might like to read the thread from the beginning and you will perhaps understand. No-one has said put a smoke in the bathroom so the waffle is from you as you have not bothered to read the posts correctly. The mention of bathrooms came from that comments regarding putting smokes on the lighting circuit...I suggest you reread what I wrote so you see the point I was making in the discussion with Sparktus.

 

[SPARTYKUS]

"ow as BS5839-6 clearly indicates that smoke/heat detectors should not be on an RCD rated at 30mA such a circuit should not be used."-tricky that bit, I'd say, one of those situations you might find yourself in with conflicting regulations.

I guess if you had smokes in a house with cabling buried in walls, that really needed to be on a 30mA RCD, another regulations conflicts with this, there must be a priority betwixt the regulations?

the technical/skilled thing I cannot back up, it was in reference to a post I vaguely remember on here so more digging required. :teeth_smile:

 

[Outspoken]

Spartykus, I think it demonstrates that that regulating bodies need to speak to each other when there is conflicting information being put out by their various publications. I believe we have all encountered examples over the years.

Clearly each and every installer should do what they personally feel is right for the installation they are dealing with, we can all sit in front of a computer and spout regulations but in reality the range of works that sparks are asked to undertake in the range of domestic properties is such that people simply need to apply bags of common sense so long as they clearly do not break any of the regulations under which you could be prosecuted or you are able to reasonably justify any deviation.

 

[Toonlad]

Just wondering Outspoken:

Why are you suddenly such an expert on domestics when by your own admittance you hate 'them' and don't do 'them'? Has never said he has never done them in the past.

Why did you only buy the BGB last month when the Regs changed last year? I presume the update doesn't apply to you? Maybe he bought a digital copy or a new replacement

I don't understand why you are waffling on about bathrooms and smokes? What relevance is this to the discussion? How many smokes do you see in the bathrooms of average houses? I guess you must live in a mansion, being super-paid as an industrial spark
nothing to do with how much you get paid, What relevance is this to this DISCUSSION

Let the lad have his say, he is being constructive and giving reason to his interpitation of the regs. If you had read his posts, yes he said he steers clear of them, But does not mean he hasnt got experiance of them. He said he would look into the regs when he got home, and he has done that, didnt need to but he has done none the less.

Lets just sit back and read what is said here, and if you or I have a different oppinion, then reply with support and reason as to why. This is how we learn, and this is why subjective regultions can be changed, as the clever people are not always that and miss the simple things.

Its a good thread, good discussion lets leave it to that please.

Regards
Toony

 

[Darkwood]

Posts 24 / 25 kinda hit the nail on the head ...you can't do right for doing wrong; Here we have conflicting regulations one that governing the safety/dangers of the cable <50mm and the other that's trying to maintain the function of a critical safety device but the way I see it as ive already pointed out that the mains linked detectors in houses will give light and sound audio warnings for many months after power failure and still operate so I cannot understand why covering a detector with a rcd is such a no no. As for the reg' that asks for a recognised difference in the cable colour again this doesn't happen in domestic, sparkies don't buy a full coil of alternative coloured sheath just to run a what would be a short in length circuit, they use the cable already in their kit. Im not discussing larger projects here like commercial industrial or multiple occupancy building here im just talking your average sized domestic install. I personally don't do domestic but do come across fire alarm installs on larger projects, im currently taking over a multiple occupancy building where each flat has its own independent fire alarm off the flats CU and all communal areas like entrances, hallways etc has a full monitored system independent of each flat.

 

[richy3333]

Bit touchy aren't you, Jesus Christ chap, you want to calm down or you'll have a heart attack. I bought a new regs book about a month ago because the last one was literally rained on when I left it on the roof of my car so I replaced it...is that acceptable to you ???

As for the experts on Domestic, I can bloody well read the regs book you know and have enough knowledge and experience to be able to understand what it and other regulations say.

Perhaps you might like to read the thread from the beginning and you will perhaps understand. No-one has said put a smoke in the bathroom so the waffle is from you as you have not bothered to read the posts correctly. The mention of bathrooms came from that comments regarding putting smokes on the lighting circuit...I suggest you reread what I wrote so you see the point I was making in the discussion with Sparktus.

Not touchy at all. My periods not due for a couple of weeks and I'm way to chilled to get angry
It's just that I've read other threads you've posted on many of which you appear to be in conflict with established forum members?

 

[Outspoken]

Not touchy at all. My periods not due for a couple of weeks and I'm way to chilled to get angry
It's just that I've read other threads you've posted on many of which you appear to be in conflict with established forum members?

With respect, just because someone is an established member does not mean their view is always right...not saying anyone is specifically wrong either, with the Regs a lot is down to interpreting what they are saying in their gobbldigook legalise and all who use them will read different bits differently, that is life.

However just because you think I had a conflict with someone doesn't really mean you should just jump in feet first unless you have read all the posts in a given thread because otherwise you end up in conflict potentially...I know that as I have done similar on a different forum (not electrical) and felt silly after..

 

[telectrix]

i would not, myself, install a fire alarm ( meaning a control panel with detectors, call points and sounders ) on a RCD. even if it meant surface wiring or earthed conduit for the drop down a wall. however, in a domestic situation with interlinked smoke detectors i would prefer to connect into a frequently used lighting circuit.

 

[tazz]

The important part missing here,is the fire alarm or mains smoke detector is there to protect life, dont make it the caurse of taking life. Personally and by the 5839, i would like to see supply taken from mcb, with no rcd protection, but if this means in domestic premises, increasing the risk of electic shock, then the wiring regs come first,
If all wiring is tested and fully compliant, there is no reason for an rcd or rbo to trip

 

[GLENNSPARK]

if you want the smokes RCD protected, trhen you must use a RCBO so that a fault in another circuit can't take the smokes out. at the end of the day, it's your call.

better them pulled of a lighting point (via FCU)....that way if you lose the power to the smokes/heats....the lighting will/should also be out......
the best way of giving smoke/heat alarm cables additional protection as well as having a clear indication of a loss of supply......

 

[tazz]

Would not disagree with that.....The be all and end all, you write your cert for the wiring making sure all is safe, and on the BS5839 p6 cert you write the variation that a rbo has been installed to comply with iee due to bathroom ceiling level, or any other Iee reg that applies.

 

[Darkwood]

I see all your sides here but one thing you all forget is if power is lost to a standard domestic mains detector with battery back-up it will still function for years .... consider a battery only detector and how many years it lasts before battery goes low.... so the whole argument about losing power is not relevant ....... im struggling to see some of your concerns here... so the danger of the detector losing power isn't a concern so the BS 7671 regarding cables <50mm takes a higher risk unless the occupants go on holidays for 3 yrs and in that time the mains trips and when they return they don't notice cos the battery is dead and that night they get killed in a house fire.....well I'll take the risk to stand my day in court if that occurs...

 

[tazz]

I see ll your sides here but one thing you all forget is if power is lost to a standard domestic mains detector with battery back-up it will still function for years .... consider a battery only detector and how many years it lasts before battery goes low.... so the whole argument about losing power is not relevant ....... im struggling to see some of you concerns here...

This was my comment earlier, and is very relevent