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The 'occasional trip' and the 2.5A leakage current don't really go well together. 'Won't reset' would be better.
Measuring the leakage down the CPC or main earth doesn't show you what's being lost down parallel paths so it's not the most accurate way of testing..
I can't see how the RCD would hold if it 'is' leaking that much.
Is it a single RCD or dual RCD board?
Are you asking for hints/tips or just informing us of your working day ahead?
You can't use the current in mA, you need to use 2.5 Amps instead.
Not a dead short at 92 OhmsIf the cooker is on and it's leaking >30mA why has it not tripped then?
2,500,000 / 1000 gives milliamps Leave I in Amps, not Milliamps
A = 2.50A
IR = 230 / 2.50
IR = 92 Ohms
if I'm correct in my calculation you have a almost a dead short somewhere?
The Rcd is faulty and there is a dodgy ring on the hob, test the rcd as per usual, at times half, one and five on 0 and 180 degrees, that will sort that bit out, then you can look at whats going on with the oven.
Not a dead short at 92 Ohms
Dead short? We got slaughtered for saying that on the 2391.
Its a joint of negligible impedance that exists, acording to the lecturer!
Boydy
It has got me thinking and cannot work on it further until landlord gives permission. Thought it might give a few of you a puzzle to think about on your sunny Sunday afternoon. I am puzzled as to why the RCD has not tripped because outwardly it looks like a Neutral Earth fault, but I have not checked yet to find out more specifically where the the problem is. The lighting and smokes are not on the RCD. Also as someone, has mentioned here already, the occasional RCD trip could be unrelated to this high residual current. Hopefully I'll get the job and will be able to satisfy my curiosity.
The 'occasional trip' and the 2.5A leakage current don't really go well together. 'Won't reset' would be better.
Measuring the leakage down the CPC or main earth doesn't show you what's being lost down parallel paths so it's not the most accurate way of testing..
Is it a single RCD or dual RCD board?
not a `dead short` anyway...as its earth fault...Not a dead short at 92 Ohms
hot?...or just measured cold?Ah yes, the current in Earthing Conductor is just part of the story. In this case it is in a block of flats so the services main bonding paths in the flat could be nicely carrying a proportion of any earth leakage current. The RCD "occasional" trip could be something else and may not even happen again. The tenant's brand new very basic cooker IR is OK, the install of this was the reason for being there in the first place.
do you think this would do the trick?It may be accumulated unless everything else is disconnected but still, I would expect to have to use an elastic band or a lock out device to hold the RCD on.
As others have already said, clamp the tails to see the true leakage of the install, you always have a good few 100 mA or so of circulating earth currents sloshing about the system on a TNC-S earthing conductor from the supply side. This is external to your installation.
hot?...or just measured cold?
well.....there you goes then..Cold. Good point about it being hot because the customer stated it tripped after it had been used for a while.
Valid point, what was I thinking eh! Obviously an earth fault as it's the rcd that's tripping.not a `dead short` anyway...as its earth fault...
do you think this would do the trick?
Valid point, what was I thinking eh! Obviously an earth fault as it's the rcd that's tripping.
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Who knows, I'd rather not try! I'm sure someone has though.
sorry Mike....lol..Oh God this is getting a little Embarrassing now, surely UK sparks knew that and was just pulling your leg, dear God surely.
I live in a flat (TN-C-S), just measured with an EL clamp meter, on the main earth it shows 247ma... and clamped on both tails shows 2.93ma. i imagine the leakage is coming from the computer. Interesting as this thread has just answered my question aswell.
Cold. Good point about it being hot because the customer stated it tripped after it had been used for a while.
I suspected you wouldn't be able to, personally I don't like holding my finger on them when MCBs pop, makes me jump when your not expecting it.
safe isolation?
Oh God this is getting a little Embarrassing now, surely UK sparks knew that and was just pulling your leg, dear God surely.
Surely you have switched a breaker on and its popped? You know, when someone rings you and says the breaker wont go on, so you go and have a look and switch it and it flicks off... Doesn't require safe isolation. I suppose the bit about not expecting it was not the right word.
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Yes I did know that, I have a way of using incorrect terminology some times!
Thank god thats that worry over with then lol
`til it gets to 2391 time...lol..
Eh?...
hmm...Post 12 about the elastic band was a joke....
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