Domestic electrical advice? - Earthing stake

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Steve Wright
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I did think about pee'ing on it but used a watering can instead, so much more civilised  :-)

Thought it may give a bit more protection for the next few days if that is where the problem is.

Derek, it is a 30mA RCD but there is only one. I'll avoid changing the board if possible, need to spend a bit on the Seven before Spring. Looks like I need to brace myself for a large'ish bill.....

Ian, managing without the Marigolds, but washing up is playing havoc with me hands. Will pop into the Body Shop next time we are in town. Provided we have any money left in the bank after this.

Norfolk AR - Member since 1996
2cv7
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If you do not want to spend any money just get him to do an rcd test and Za test. Max Za on TT system with a 30ma rcd up front is 1667 ohms but less than 200 is advised as preferable.... If the rcd is a BS 61008 then it needs to trip within 300ms on 1x trip current and 40ms 5x trip current, BS 4293 is 200ms. Also the test button must operate the device.  Or you could just chuck the toaster in the bath and see what happens....Just remember many sparks are clueless about TT systems....

Spend the money for a new board on some upgrades.

Elliott

Derek Batty
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Hi Elliott 

the poor  sod wont be able to sleep tonight ,,wondering what it’s going to cost ,, most systems on iom are TT except new developments 

derek

left Yorkshire came to iom 1971  never seen an earth rod till got here 

Mark w
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Ive read recently that a lot of folks having home electric car charging points fitted are having to have a supplemental earth rod driven to meet the "new"regs .

If you think you might have an electric car in the future see if you can get any remedial work done so that it meets the charger requirements so you dont have any need for another upgrade at a later date .( think where you might fit a charge point ) 

Steve Wright
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That's really interesting Elliot, it may be within spec.

It's definately a TT system. There is no earth connection in the power feed, just live and neutral, plus an earth stake outside, near the front door.

How is Za measured? The Hotpoint engineer had a device that plugged into one of the 13A wall outlets. I was unsure how you could measure earth impedance when you only have a Live, Neutral and Earth connection to work with.

The RCD is BS 4293 so needs to trip within 200mS at 5x current.

I guess the electrician will be able to do these measurements and maybe provide certification with a bit of luck. Not being tight when it comes to safety but don't want to spend where it's not necessary.

Think I'll pass on the Toaster test, thanks :-)

Steve

 

Norfolk AR - Member since 1996
Jonathan Kay
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Ive read recently that a lot of folks having home electric car charging points fitted are having to have a supplemental earth rod driven to meet the "new"regs .

If you think you might have an electric car in the future see if you can get any remedial work done so that it meets the charger requirements so you dont have any need for another upgrade at a later date .( think where you might fit a charge point ) 

If anyone's wondering what's special about charging EVs at home it's when they or the charging point are outside the house with a specific type of earthing system.

Good advice to think ahead.

Jonathan

PS:

I've heard of dogs being surprised peeing on electric fences for livestock(probably urban myth!)

We've recently discussed the megger trick on apprentices. Mythbusters have covered both the third rail and the electric fence: Busted and Confirmed respectively. 

Ian B
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Steve, the plug in device compares the earth to the neutral at the socket. As neutral should be at similar potential to earth it can measure the difference between them - if the neutral is floating significantly above earth potential at the socket then it indicates the earth at the socket is not a good connection to "ground".

The Completely Superior Ride Seven Wink

Ian B
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Alternatively, it's just magic Laugh

The Completely Superior Ride Seven Wink

Wrightpayne
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Electrikery!

Derek Batty
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So I can say ,,,before I retired I was not an electrician.  ,,,I was a magician ,,specializing in words 

derek