RCD being used as a main switch

[Paul Hamill]

Is it against the regs to use and RCD as a main switch ? I have been told it is but Im struggling to see anything that confirms so. Im looking at 314.1 in the regs book but that doesn't say anything about an RCD being used as a main.

Any feedback would be greatly appreciated.

 

[Midwest]

That's going to make some domestic CU's with TT supplies problematic.

 

[Paul Hamill]

Im not installing one personally but I am inspecting a lot of facilities and there has been RCDs used as main switches. Thats why I ask.

 

[Midwest]

Sorry, as its a Bank Holiday being a bit flippant. You could use an S Type RCD as main switch on TT supply, as it negates issue of internal single insulated manufacturers tails on dual RCD's, shorting on metal enclosure. You could use a 30mA RCD as main switch on small garage CU etc. But if you used a 30 mA on larger installs, it would (not) provide very good division of services, would it?

Edit

 

[Leesparkykent]

The regs aren't going to explicitly state about using an RCD as a main switch etc. Its about division to minimise disruption.

 

[Flanders]

As lee says its about avoiding disruption from nucence tripping i think there is a reg number for that , so try looking in the regs book for that

 

[Octopus]

In some cases its unavoidable ....

 

[Paul Hamill]

I know its going to cause nuisance tripping and not ideal but I am was looking for a reg to back up that its not correct. We are doing inspections and have been told to pull it as being a Life health safety issue. Thats the term they use out here for a C1. Would any of you back home write it up as a C1 ?

 

[Octopus]

I know its going to cause nuisance tripping and not ideal but I am was looking for a reg to back up that its not correct. We are doing inspections and have been told to pull it as being a Life health safety issue. Thats the term they use out here for a C1. Would any of you back home write it up as a C1 ?

Absolutely NOT

C3 maybe but I think you would struggle to justify that.

 

[Leesparkykent]

I know its going to cause nuisance tripping and not ideal but I am was looking for a reg to back up that its not correct. We are doing inspections and have been told to pull it as being a Life health safety issue. Thats the term they use out here for a C1. Would any of you back home write it up as a C1 ?

no

 

[Flanders]

I know its going to cause nuisance tripping and not ideal but I am was looking for a reg to back up that its not correct. We are doing inspections and have been told to pull it as being a Life health safety issue. Thats the term they use out here for a C1. Would any of you back home write it up as a C1 ?

How can there be a danger to life or property due to the main switch being an rcd, remember as others have said some installations have to have an rcd as a main switch , the most it would get is a code 3 or just info

 

[Paul Hamill]

Thats my argument, to me its not unsafe to be used as a main, just bad practice in certain situations. Thanks for the replies.

 

[Midwest]

Unless the property had essential medical equipment reliant on electrical supply.

 

[Deleted member 26818]

For many this is not just bad practice, it's a non-compliance which would in some cases warrant a code C2.

 

[Midwest]

Reminds me of another from our American cousins;

 

[Des 56]

I know its going to cause nuisance tripping and not ideal but I am was looking for a reg to back up that its not correct. We are doing inspections and have been told to pull it as being a Life health safety issue. Thats the term they use out here for a C1. Would any of you back home write it up as a C1 ?

Whilst trying to justify some sort of reason for a perfectly healthy electrical system,it was suggested that Granny could tumble down the stairs in the dark and meet her maker ( her faulty Teasmade failed to make the late night cuppa)

The moral of the tale is that Granny should not rely on a single Rcd or she may be safer drinking squash

When one Rcd was the norm,the terrible danger should have been made known to the 100% who managed to survive

 

[Deleted member 26818]

Not aware that one RCD has ever been the norm?

 

[Flanders]

Not aware that one RCD has ever been the norm?

Ive seen a lot of house on tncs supplys with one main rcd , some i know were built in the early 90s when the 16th addition had just com out.

 

[Deleted member 26818]

One RCD covering everything, or just one for down stairs sockets?

 

[Ian1981]

Coding is down to the inspector of the installation.
If you feel strongly that a rcd main switch gives potential danger then code it.
If you think it's inconvenient at best but isn't a safety issue note it on the eicr.
An rcd tripping causing loss of power to the upstairs lighting can still occur with a dual rcd db yes hopefully the upstairs sockets aren't effected and a bedside lamp can be used for lighting.

 

[Des 56]

Not aware that one RCD has ever been the norm?

Then you never lived in my part of the world to see in the early seventies
If there happened to be any sort of circuit breaker it would have been a voltage operated elcb
The Rcd that replaced these were fitted to almost every household electrical system that existed in that location

 

[HandySparks]

Then you never lived in my part of the world to see in the early seventies
If there happened to be any sort of circuit breaker it would have been a voltage operated elcb
The Rcd that replaced these were fitted to almost every household electrical system that existed in that location

Quite.
Loads of houses on a TT supply with one upfront ELCB or RCD.

If total loss of power is regarded as a significant safety issue, then emergency lighting or an automatic-start backup generator should be installed to cater for power cuts. Or a UPS fitted to specific items of essential equipment.

 

[Specialist]

Yep: Front end ELCB or RCD covering the whole installation was the norm down here too, still lots of them in daily use.

 

[driverman]

OP, are you referring to a domestic installation?
On a distribution system, many installations use a RCD as main isolation switch.

 

[electric al]

Err how can a bedside be used and how can the sockets not be affected ?? The point is the rcd is the main isolator switch and also controls all circuits !

 

[Ian1981]

Err how can a bedside be used and how can the sockets not be affected ?? The point is the rcd is the main isolator switch and also controls all circuits !

Talking about a dual rcd db and that you can have up lights on one rcd and up sockets on the other thus if rcd protecting up lights trips then at least a bedside lamp can be used on the upstairs sockets so there can be some light.
Read it again!

 

[electric al]

 

[electric al]

Picture of one such installation I visited
Just today

 

[Ian1981]

Picture of one such installation I visited
Just today

I'm lost!
I was referring to a dual rcd consumer unit I would have to go and read through the entire thread again to see what context I brought this up with.
Hope you commented on lack of circuit identification tho

 

[electric al]

Yeah good idea - re read the thread .
The convo wasn't about a dual rcd .

 

[Ian1981]

Yeah good idea - re read the thread .
The convo wasn't about a dual rcd .

Na thread was a week ago we've all moved on since!

 

[electric al]

Always best to stick to the point . Seems you like to throw the odd Spaniard in the works . Still there ? Move on fella

 

[Ian1981]

Always best to stick to the point . Seems you like to throw the odd Spaniard in the works . Still there ? Move on fella

Like this thread, I already did "move on"

 

[electric al]

Be relevant then . Commenting on Australia in a geography exam , when the
Question is about China will get you marked down lol

 

[MrLights]

I've never ever used RCD's in a domestic installation. Split load 2 RCD boards are not for me! 100A main breaker/isolator with RCBO's is the only way. AMEN

 

[i=p/u]

Double pole

 

[Mike Johnson]

Double pole

Only true Double Pole RCBO's not those silly things with fly leads.

 

[ferg]

Not bad.. more than 3 years old and still an active thread.

 

[Mike Johnson]

I some times feel as though I have been resurrected as well, especially first thing in the morning.

 

[LastManOnline]

I've never ever used RCD's in a domestic installation. Split load 2 RCD boards are not for me! 100A main breaker/isolator with RCBO's is the only way. AMEN

Amen to that. My preferred method since 1998.With the 63 amp main switch in place of the 100 amp (don't have them yet)