element resistance

[electrocuted]

good afternoon,

got called to a shop where the rcd is tripping, checked everything and the only thing causing the tripping is a filter coffee maker with 2 separate elements.

The question is how do you test the elements in term of resistance of the elements.ahd how do you work out what kind of results you look for .

thanks for the replies

 

[ianmacd]

If the RCD is sripping wouldn't it be earth leakage not the resistace of the elements otherwise wouldn't the MCB trip instead?

Ian.

 

[green-hornet]

If you have one do a portable appliance test on the coffe machine, my tester has a digital reading and a pass or fail indicator.

 

[a1]

What meter and model might that be Green-Hornet?

Thanks.

 

[Gforce]

If the RCD is sripping wouldn't it be earth leakage not the resistace of the elements otherwise wouldn't the MCB trip instead?Ian.

my thoughts exactly-though Im just learning. maybe if the element is broken in some way and the live is exposed onto the surface as such-wouldnt the metal of the element be naturally earthed for safety and this is maybe where the earth leak is coming from.

I dunno just spit balling-I look forward to this sherlock holmes part of the job lol.

 

[green-hornet]

I have the kewtech KT 71 listed in screwfix for

 

[electrocuted]

the machine works if you move it the non rcd side,but trips the rcd ,there is an earth leakage which I am assuming is caused by the elements.

 

[green-hornet]

In that case the machine and not the wiring is at fault.

I had a call from a rewire I did, they complained that every morning the rcd tripped.

First thing I did was to get the portable appliances checked out in the kitchen (the every morning was the clue) turned out to be a toaster.They was convinced it was the wiring, until I turned the toaster on then 2 minures later the rcd tripped.

Her reply was funny that, I was making toast when it went off last time!

 

[Theorysparky]

I have the kewtech KT 71 listed in screwfix for

 

[batty]

Could also test with insulation tester if you havn't got pat tester. Test live to earth and neutral to earth at 250v and see what resistence is you could just do it across plug top.

Batty

 

[seajayess]

Use an insulation tester on the elements between the element and CPC, if you try a pat tester it will prob fail it unless you can alter the parameters of the tester. If you want to know if the elements have failed use a low resistance ohms meter on the element between Line / Neutral element connections, use power triangle and ohms law to calculate the resistance of the elements, don't forget if the elements are connected in parallel you will need to calculate what the Resistance should be CJS

 

[green-hornet]

i have the same onegood for testings stuff in rented properties and rcd trip faults

wouldnt recommend it if all i did was pat testing

I agree I only got it because of a one off jobby but does come in handy for such events that I described