Thats an interesting thought - thanks for that. That would get my paperwork sorted, but I suppose it is a bit of a fudge, as the underlying problem still exists.
Since my original post, I actually have a dual rcd board that I took out from another job which could be adapted to solve this issue.
Thanks for all the replies. Indeed I agree with all, complete brain freeze and forgot my original reasoning for splitting the earth was nothing to do with the RCD's, but to avoid using the PME over such a large distance to the outbuilding. The complication with trying to work out a solution, is...
Yes you are absolutely right, must be this heat, my brain is swiss cheese right now. Surely there must be a way that i can ensure a fault in the outbuilding will not cause the RCD in the main house to trip but only the RCBO on that circuit, or is my design fundamentally flawed ?
Unfortunately the main board is covered by a single Type AC RCD, so i added an MCB to cover the SWA thinking the RCD would cover that cable. I didnt think for a second that even with earths separated that selectivity would be an issue. If that is the case then ill have to put in a 100ms time...
Hi
Ive looked around and i cant see this particular scenario being discussed.
I think i may have been a numpty, but bear with me.
I have just completed an electrical install into an outbuilding. Its distance meant i went with installing its own earth rod, thus not exporting the pme from the...
Ok, thanks. Interesting to get people's views on that. Yes I notice a lot of sparkies using them on the RCBO neutrals once they've been shortened. I use them a lot inside CU's on the screw terminals, just wondered what the views were on using them within the MCB's etc.
How do you deal with stranded single cable into a MCB/RCBO ? Would you ever ferrule stranded 1.5 or 2.5 singles into a MCB/RCBO ? I can't see a reason why not except for the length of the ferrule pin, although i believe you can get different lengths. I dont believe there is anything in the regs...
Having a bit of a brain freeze moment.
I have a 2-core SWA cable running to an outbuilding. The sheath is used to earth this cable back to the consumer unit in the house which is TNC-S, while the outbuilding has its own earth electrode (ie it's TT) protecting its Consumer Unit. That's to say...
Done this loads of times before, but this situation is quite unique so bare with me.
I've been asked to cable up an out building at a country park which is about 30m from another out building which has mains supply already installed from a main building some distance away via a 10mm SWA buried...
He's a question for you.
What (if any) are the dangers of working INDOORS on an electrical circuit during a Thunderstorm ? Heck you would have to be stupid to work outside in one, but I was considering what would happen if there was a nearby strike and I was working on an open consumer unit...
Hi,
I'm getting conflicting stories about this, I wonder if someone could put this to bed once and for all.
I'm replacing a consumer unit in the next few days, and it currently has the common grey tails going from the isolator to the existing consumer unit, one is ,marked "L" then other marked...
Hi, I've had an unusual result from taking a Ze at a clients house and wondered what everyones take on it would be:
The property is TN-C-S
A Ze reading from a disconnected Earth to Line gave a reading of 0.45 ohms
A Ze reading from the Line and Neutral gave a reading of 0.33 ohms
A TN-C-S...
Hi. Now I'm pretty sure why this is happening, but I thought I'd check.
Just did a standard RCD test at a client, and the RCD failed the test. Did a Ramp Test to check it and it finally tripped at 100mA. It's an AC RCD, so my guess is it's an appliance or something leaking DC current high...
Lets see if my Competent Persons assessor agrees shall we before you make assumptions as to whether I'm competent or no !! Answer the question, don't make comments about me.
Hi,
I've got to put in an additional consumer unit into quite a large property and rather than daisy chaining them back to a single MCB in the main board which is RCD protected, I wondered if this a better solution: The property is served by TNC-S with an isolator switch.
Connect new tails into...
I've not come across this before. The current regs state it should be on a 32A MCB. I've been asked to re-wire a bedroom which will involve extending this ring. It already serves two other bedrooms and the lounge. I know I probably should tell the client to upgrade this MCB to 32A, but is it...
Thanks for the comments. Certainly can understand its height if this was a commercial property but it's a private residence with an elderly couple. Every time it trips they have to get a long pole to reset the breaker, they are unable to climb ladders anymore
Ive been called in to check and repair some electrics in a large domestic garage/workshop that keep tripping, but I've been confronted with a CU that's at least 3m ffl (it's a high ceiling with open rafters). As I've got to test everything in the CU, I'm highly tempted to recommend to move it to...
I've been called in to complete a job started by someone else and I just wanted to ask the following:
Basically it's to provide power to a garage and then on to provide power to a Summer House. What has been done already is a PVC conduit has been buried under the patio between the main house...
I'll post a photo tomorrow, but it's a lot, at least 1cm or more. The only place copper should be showing is at the neutral or earth bars, the bus bar should be covered. As a matter of interest the codebreakers book states any copper showing on line conductors is at least a C2
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc