Rcd as main main switch?

[whazza22]

Just a quick one.

Is it acceptable to have a 63a 30ma Rcd as a main switch?

Can't see why not but just thought I would see what others say?

 

[plugsandsparks]

Could be, or not depends

 

[whazza22]

What would it depend on?

 

[plugsandsparks]

Whats on the board and comm or domestic

 

[Newbie90]

Domestic, one bed flat.

1 lighting circuit, 1 ring, cooker and shower

 

[GLENNSPARK]

i think i`d be using a DP mainswitch (a 100mA s type RCD would be good for this)...
RCBOs for the finals...

 

[Newbie90]

i think i`d be using a DP mainswitch (a 100mA s type RCD would be good for this)...
RCBOs for the finals...

The rcd was supplied with the 6 way consumer unit. I prefer rcbos but are too expensive

 

[Crosswire]

I hate having RCD's as a main switch. Does not "minimise inconvenience in the event of a fault"

If anything, it does the opposite.

 

[GLENNSPARK]

I hate having RCD's as a main switch. Does not "minimise inconvenience in the event of a fault"

If anything, it does the opposite.

yeah well thats it isn`t it...
to the O/P....look,
you`v got four finals in there....i mean whats this C/U anyway?..electrium? crabtree?

whats the earthing arrangements as well...

 

[Des 56]

Yes there is minimising inconvenience,but I suspect that reg was put in there mainly for commercial or factory operations, where the whole place gets to be sitting idle whilst a single problem gets sorted and it then becomes of importance :nono:

In a domestic,how inconvenient is the loss of all circuits ? when there is a power cut, or someone does not have a shilling for the meter,it matters not what is the make up of the board in that situation
The twin Rcd jobbies are in themselves a botch of what may be the true intentions of the reg when applied to domestic

My own home has one Rcd covering the whole of the installation,yet it's never inconvenienced me at all :26:

Its applied in domestic but the way I look at it, One Rcd is not as good as 2 Rcds which is not as good as 1 rcd and a few Rcbos which is not as good as all rcbos which is not as good as all rcbos and an emergency light
It can become never ending :death:

I kmow it is not the done thing these days,but it's no big deal either
The Rcd board could be used, then he could install an emergency light,get it shoved in for some sort of home comfort should the Dno or a fault play games with the install and cause the ultimate inconvenience for the householder

 

[GLENNSPARK]

Yes there is minimising inconvenience,but I suspect that reg was put in there mainly for commercial or factory operations, where the whole place gets to be sitting idle whilst a single problem gets sorted and it then becomes of importance :nono:

In a domestic,how inconvenient is the loss of all circuits ? when there is a power cut, or someone does not have a shilling for the meter,it matters not what is the make up of the board in that situation
The twin Rcd jobbies are in themselves a botch of what may be the true intentions of the reg when applied to domestic

My own home has one Rcd covering the whole of the installation,yet it's never inconvenienced me at all :26:

Its applied in domestic but the way I look at it, One Rcd is not as good as 2 Rcds which is not as good as 1 rcd and a few Rcbos which is not as good as all rcbos which is not as good as all rcbos and an emergency light
It can become never ending :death:

I kmow it is not the done thing these days,but it's no big deal either
The Rcd board could be used, then he could install an emergency light,get it shoved in for some sort of home comfort should the Dno or a fault play games with the install and cause the ultimate inconvenience for the householder

well i know i advocated the application of the RCBO here Des...on the basis there were only 4 finals...
any more and i would have suggested a split load....

 

[Des 56]

well i know i advocated the application of the RCBO here Des...on the basis there were only 4 finals...
any more and i would have suggested a split load....

I think your advise was spot on Glenn

I was more trying to make a point to the general forum that I don't get too excited when the "Oh my God, one Rcd" type reactions come into some threads

That's not to say I would advise the guy to go instaling them instead of a better class of set up

 

[Deleted member 26818]

It's acceptable (just) in a new installation.
Not really for a replacement, unless it's a like for like replacement.

 

[Welchyboy]

Although not inherently wrong, it is frowned upon and it would be a last resort for me
I would not sit comfy with the fact of installing a single RCD up front for my own reasons, if they do get any issues in the future, be it with the installation or a dodgy appliance, and it trips and they can't re-set it, then as you installed it it will likely become your emergency to try and get to them ASAP and get their power on again,

I would at least try and install a dual rcd so that if you do get problems they can run a few extension leads and lamps out and give you a little breathing space if needed

having said that with only 4 circuits and if its a new install you should be ok, but you know how things have a habit of coming back to bite u lol

 

[Heisenberg]

It may not be an inconvenience to some, but some of the biggest computer problems come about because of dodgy power supplies. I can promise you this, if a PC loses its power in the middle of doing something there is always the chance that the HD will be corrupted beyond repair, resulting in catastrophic data loss. So having the main switch go, whilst someone is using a PC is not an ideal situation.

A mate of mine who was frustrated with his PC simply switched it off at the mains, and was then surprised when he switched it on again and it wouldn't boot. The upshot was that he lost everything on there, including some pictures of his young newly born son. I'm still not sure if his wife is talking to him.

The point I'm trying to make is that these days, your average home has more and more devices in it that don't like sudden loss of power.

 

[Newbie90]

That would still happen if there was a fault on the ring main causing the mcb to trip.

 

[Rampantchilli]

Minimise inconvenience in the event of a fault

well inconvenience can be perceived differently depending who you are, and what your doing.
Rcd trips while your washing machine is on at night, turns off your alarm clock, your clothes ain't ready for work in the morning and your late. That's inconvenient.

your baby has to have his music playing to get to sleep, your 'on the job' with mummy and the power cuts, that's frustrating.

Your 83 in your house on your own, the Rcd trips, no lights no power no central heating, you fall over the coffee table and break your hip, you lie on the floor for 3 days, in agony, til you freeze to death, more than a little inconvenient. But at least the electrician saved £60 on his job, that you paid him what he asked for.

really tho, where is the harm in using 2 rcds, or in this instance 4 rcbos

 

[Heisenberg]

That would still happen if there was a fault on the ring main causing the mcb to trip.

Of course, but a much more likely occurrence if the whole install was on an RCCB.

 

[Crosswire]

Domestic, one bed flat.

1 lighting circuit, 1 ring, cooker and shower

I can see why they did it in this case, as the install is too small to practically subdivide. If RCBO's cost the same as MCB' everyone would use them, everytime. Shame really.

 

[Fin170]

As a minimum Split board, sockets on rcbo and everything else on the rcd side with at least 2 spare ways

To improve on that

All RCBOs

Or as it's a bungalow you could probably divide up the light (and possibly socket) circuit easily. Maybe they have their boiler controls spured from the ring? Run a dedicated spur from the board for it (non rcd). Add an emergency light, Add fire alarms (we do this free (-materials) if it's straight forward) or install a double socket by the fuse box on it's own circuit

The basic convince upgrade possibilities are endless pending budget

 

[Octopus]

Just a quick one.

Is it acceptable to have a 63a 30ma Rcd as a main switch?

Can't see why not but just thought I would see what others say?

Acceptable - maybe just, good practice - definitely not.

 

[Engineer54]

The rcd was supplied with the 6 way consumer unit. I prefer rcbos but are too expensive

Do you think these RCBO's are too expensive?? Combine with these RCBO's with one of their CU's and you have a very reasonably priced all RCBO CU!! An all RCBO CU is the real deal, these dual RCD CU's are nothing but a compromise, and can be a bloody headache trying to find leakage faults...

TYPE B - 10kA, Consumer Units, Fuse Boards, Fuse Box, MCB, RCD from Wyeverne Electrical

 

[vicghirawoo]

Yes you can. And it is cheaper to purchase a main distribution panel with a RCD main breaker than having individual circuit RCD breakers.

 

[Octopus]

Yes you can. And it is cheaper to purchase a main distribution panel with a RCD main breaker than having individual circuit RCD breakers.

BUT you wouldn't install like that in a new/rewire situation because it wouldn't comply with the regs,

 

[dazzer-b]

bloody hell you are making that question hard work, its a switch to isolate the supply, an rcd does that so yes its fine.

 

[dazzer-b]

Acceptable - maybe just, good practice - definitely not.

this answers the question perfectly, just winds me up when busy boddies get involved to try and answer the question better than others to prove how superior they are.

 

[Octopus]

this answers the question perfectly, just winds me up when busy boddies get involved to try and answer the question better than others to prove how superior they are.

You need to read post #24 too.

 

[vicghirawoo]

bloody hell you are making that question hard work, its a switch to isolate the supply, an rcd does that so yes its fine.

Couldn't agree with you more!! Let's move on. :83:

 

[Richard]

i think i`d be using a DP mainswitch (a 100mA s type RCD would be good for this)...
RCBOs for the finals...

Why would you use a 100mA s type as the main switch as opposed to just a main switch?

 

[Bengaz]

Domestic, one bed flat.

1 lighting circuit, 1 ring, cooker and shower

There should be minimum 2 lighting circuits and 2 ring mains in that flat using a minimum of a dual RCD board (DP main switch) (£46 complete). That wouldn't cost any more surely and fully comply.
Fully minimizing inconvenience...

 

[Octopus]

Couldn't agree with you more!! Let's move on. :83:

I couldn't disagree more with you.

If the installation is new, or a replacement CU then a single RCD DOES NOT comply with BS7671. A small flat with 3 circuits should have an RCBO for each circuit.

 

[dazzer-b]

I couldn't disagree more with you.

If the installation is new, or a replacement CU then a single RCD DOES NOT comply with BS7671. A small flat with 3 circuits should have an RCBO for each circuit.

oh well.... im sure you'll sleep at night

 

[baldyphil]

Just to hurl another moggy in... so the general consensus is that using an RCCB as a main switch is not considered good practice due to the 'convenience factor' meaning it doesn't meet the minimum split load requirements of the 17th, but... how about a household with 16 circuits split equally over 2 separate crabtree boards - one board uses 80A RCCB as main switch whilst the other has a 100A DP as main switch and no RCD protection (this isn't hypothetical, btw, but characteristics of a property I worked at recently). If the 100A DP was swapped for an RCCB (80A would easily meet the everyday requirements of the board), would this be deemed good practice as it would effectively give the same level of protection and convenience as an upgrade to a split load 16-way board at a fraction of the cost to the client? Apologies for the verbal diaorrhea...:smiley2:

 

[GLENNSPARK]

Just to hurl another moggy in... so the general consensus is that using an RCCB as a main switch is not considered good practice due to the 'convenience factor' meaning it doesn't meet the minimum split load requirements of the 17th, but... how about a household with 16 circuits split equally over 2 separate crabtree boards - one board uses 80A RCCB as main switch whilst the other has a 100A DP as main switch and no RCD protection (this isn't hypothetical, btw, but characteristics of a property I worked at recently). If the 100A DP was swapped for an RCCB (80A would easily meet the everyday requirements of the board), would this be deemed good practice as it would effectively give the same level of protection and convenience as an upgrade to a split load 16-way board at a fraction of the cost to the client? Apologies for the verbal diaorrhea...:smiley2:

eh?....
try safety...as in you don`t want all the lighting to stop working...should the RCD let go...
and whilst were at it...ever heard of accumilated earth leakage....
split final circuits up as evenly as possible between 2 RCDs...or each final with its own (RCBOs)
think before posting nonsense will you

 

[Engineer54]

Why would you use a 100mA s type as the main switch as opposed to just a main switch?

This only makes sense in a TT installation, where the up front S type RCB is providing back-up protection on failure of the 30mA RCD(s). Not much point on a TN system, .....that'll be giving you 3 levels of protection!! lol!!

 

[dazzer-b]

Just to hurl another moggy in... so the general consensus is that using an RCCB as a main switch is not considered good practice due to the 'convenience factor' meaning it doesn't meet the minimum split load requirements of the 17th, but... how about a household with 16 circuits split equally over 2 separate crabtree boards - one board uses 80A RCCB as main switch whilst the other has a 100A DP as main switch and no RCD protection (this isn't hypothetical, btw, but characteristics of a property I worked at recently). If the 100A DP was swapped for an RCCB (80A would easily meet the everyday requirements of the board), would this be deemed good practice as it would effectively give the same level of protection and convenience as an upgrade to a split load 16-way board at a fraction of the cost to the client? Apologies for the verbal diaorrhea...:smiley2:

ive installed a 15 way split load DB on numerous occasions, you only have 1 more way. ok i did have the option of splitting up the lighting circuits and rings.

i say go ahead there are a lot of busy people on this site that get their tears out and find something negative with every post.