# Element tripping house RCD, advice please.



## claypot (8/7/14)

Hey All,
I've just started running up my single vessel brew rig. Here: http://aussiehomebrewer.com/topic/57924-braumeister-nextgen-build/page-83#entry1196086
It has a 3kw heating element - EBay $17 : http://www.ebay.com.au/itm/220V-3000W-Stainless-Steel-Electronic-Tube-Heating-Water-Heater-Element-/351101449889?pt=LH_DefaultDomain_15&hash=item51bf46f6a1
All was going well during tests then went to fire it up for a brew and element tripped the house RCD strait away. I have an ammeter on the panel and I had been getting a spike to over 15 amps settling on 13 - 15 amps. I have the vessel earthed. I only have a multimeter at home and the element was not down to earth. I removed the vessel earth for a brief test, and the RCD didn't trip and no excessive current was drawn. Not really sure what's up as I can't mega the element until I go back to work in a couple of weeks. All appears to be sound in the panel. The rig is in the shed, that has a 16amp breaker, from house 32 amp breaker, from house common RCD. Only the house RCD is tripping, no breakers, rig amp meter only gets to 5 or so amps and is a very steady rise. I have another element on it's way - 20 + days.
Anyone having good / bad results from Chinese elements?
Any help much welcomed.
Cheers Clayton.


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## dicko (9/7/14)

I would advise you to seek the help of a person qualified in electrical installations.
The problem could be from many number of reasons.
Play safe mate.


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## Maheel (9/7/14)

if you check the resistance from the element power lug to the "vessel" are you getting 0
this would check the earth and a basic check on the element

it might also be earthing under load (buggered element inside etc)
your RCD might not like the +15amp ?

I had a RCD on my 15amp shed line that was part of a recall they found a fault in them and some would not trip.....
on the day i had it replaced it did not want to trip very well.... = dangerous

like Dicko said get a pro to have a look and stay safe


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## zappa (9/7/14)

This used to be a common problem in various elements back when I was an appliance tech. We usually put it down to cracks in the internal insulating material (often ceramic) that would cause an earth leak only when it started to heat & expand.

It could be just moisture in your case though. Doesn't take much to trip an RCD, even with extremely high resistance. Make sure the element is completely dry around the posts. 

If in doubt, take it to a sparky and ask them to check it for you though. Mains power can be deadly, especially when there's liquid involved. Not worth screwing around with if you're unsure about what you're doing.


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## hairydog (9/7/14)

Hey Claypot,

Elements are notorious to have current leakage to earth,especially if they are not manufactured to AUS standards,

RCD only need 30ma or more to trip,the element may have some moisture in mineral insulation within copper tube of

element,sometimes this improves or dries up the more its used.You can have the appliance tested and tagged by aproved

companys which will test leakage to earth,or try a new element,hope this helps.


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## claypot (9/7/14)

Hey All thanks for the replys.

Totally agree if your unsure or not trained in electrical installations you shouldn't be messing with it.
We only need look to the news to see sad examples of people injured and killed from the dodgy USB chargers.
On that note, I am not a residental sparky, however I have a Marine Egineers ticket that allows me to repair and maintain ships electrical systems whilst at sea.
It was my understanding that when fitting a RCD to a house board, the hot water service and oven is left off the protected side due to the elements causing them to trip. I have had a RCD fitted to my last 2 houses by 2 differnt sparky mates, who both left the hot water service and oven off due to the fore mentioned.
So my question to others is : Are your rigs working happily on RCD protected circuits when over 3kw? If so I may need to have an element manufactured.

Prior to the drama I was having I had tested the heating to boil for over 2 hrs to make sure all was good before adding / wasting grain. All went well. It probably sat for 3 or 4 days till I had the time. It tripped the RCD strait away.
I checked the resistance across the rig, vessel and earth etc all good.
Probably as zappa and hairydog have metioned, the smallest of unbalance across the phases from a less that perfect element is all it takes. And most likely due to the cheap element I'm using. All the same I will get the element megared at work to pinpoint the problem.
Cheers again.


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## claypot (10/7/14)

So quick follow up. Pullelled the element and found a hole where it had been sat against the bottom of keg/vessel. If you dont earth your elements and rig your mentle! Must of been the vibration against the vessel as it pulsed.


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## Bribie G (10/7/14)

Nasty. I've found that (apart from a toaster) every RCD trip out has been due to some equipment where water and electricity has been in close proximity: cheapy floor steamer, not so cheapy Bissel carpet shampooer :angry: and a couple of electric kettles.

Good you can get a replacement, anyway. What had you been doing to it .. looks like it's been seriously insulted during its short career  you weren't trying a protein rest or something ??


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## mrsupraboy (10/7/14)

Looks like the rcd just saved Ur life


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## MaltyHops (10/7/14)

claypot said:


> So quick follow up. Pullelled the element and found a hole where it had been sat against the bottom of keg/vessel. If you dont earth your elements and rig your mentle! Must of been the vibration against the vessel as it pulsed.


That element looks like it's made of copper and if your pot is stainless steel and the element was in contact with the pot when wet, the hole may have been caused by:

_Galvanic corrosion_ ... _WIKI _

I left some copper tubing from a mash tun manifold on a s/steel plate to dry once and green copper oxide formed pretty quickly - doesn't happen when left on a plastic plate instead.


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## sp0rk (10/7/14)

claypot said:


> So quick follow up. Pullelled the element and found a hole where it had been sat against the bottom of keg/vessel. If you dont earth your elements and rig your mentle! Must of been the vibration against the vessel as it pulsed.


That looks like a blow out (seen many when I worked for an element maker)
Probably moisture in the element and it's shorted across the moisture
Chinese made elements are very notorious for moisture in the insulation powder
I'd say buy an Aussie made U Bend It element or hit up someone like Thermal Electric Elements, Roband or Heatcraft to source one to suit


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## claypot (10/7/14)

Bribie G said:


> Nasty. I've found that (apart from a toaster) every RCD trip out has been due to some equipment where water and electricity has been in close proximity: cheapy floor steamer, not so cheapy Bissel carpet shampooer :angry: and a couple of electric kettles.
> 
> Good you can get a replacement, anyway. What had you been doing to it .. looks like it's been seriously insulted during its short career  you weren't trying a protein rest or something ??


Yeah this All grain gig is all trial and error at this stage! I blame the Adelaide water for the build up!


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## claypot (10/7/14)

Cheers for the info maltyhops, but the element is stainless. I was concernered that the element was pushed against the vessel when I fitted it, didn't take the curve in the base into account.

Yip good point mrsupraboy, RCD was the way forward.....

Yeah sp0rk, I have heard good things from Romar elements in Vic, from a couple of other post's here so will get on to them. Will try the others you suggested too, cheers. That way I can get it made to the perfect measurements. $17 dollars delivered seemed to good to be true...


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## MaltyHops (10/7/14)

Maybe the problem is caused by beer stone buildup - see _Re: Element failiure explosion_ - maybe the build up insulated the element and being right next to the pot made it worse with less wort around it to carry heat away.

But was the element quite new when you put it into your system? Odd that you should get so much build up so quickly if so.


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## claypot (10/7/14)

MaltyHops said:


> Maybe the problem is caused by beer stone buildup - see _Re: Element failiure explosion_ - maybe the build up insulated the element and being right next to the pot made it worse with less wort around it to carry heat away.
> 
> But was the element quite new when you put it into your system? Odd that you should get so much build up so quickly if so.


That's a good read cheers.
Couple of good points there. Didn't really think about the amount of scale, as is first AG brew. It has done about 2 hours over various temps with just water during tests, it was still pretty clean after. Then about a 70 min mash at 65 deg, stepped to 70 deg for 10 min. Then a 70min boil. I think the location right on the bottom of the keg isn't helping as not getting much flow over it. The idea I had was that the whirlpool pipe in the bottom would cause enough swrilling flow, then carry into the grain bed via the slotted pot. However during the boil the pump is off.


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