EARTH LEAKAGE MEASUREMENTS

It is a requirement of the Wiring Regulations that electricians measure the earth leakage currents in an installation upon completion of their work.
By testing that the earth leakage is within acceptable limits we can have more confidence that the installation will not suffer from unwanted or nuisance tripping.
Many electricians, however, do not fully understand all the requirements and implications of the Wiring Regulations, so this video has been compiled to help everyone have a greater understanding.
An electrician will often be called upon by a customer with an RCD that is tripping every day, every evening and so on. The electrician may carry out certain tests in an attempt to uncover the cause, but may miss certain vital clues because the tests are not carried out fully.
In this video we hope to address those issues and hopefully help you to gain more knowledge in order that you can confidently approach those nuisance tripping problems.
A logical and methodical approach to fault finding for nuisance tripping will often uncover the problem.
To view all our videos, click on the following link
/ @learnelectrics4402

[@paulhayles6947]

I never change a consumer unit without checking the earth leakage. If it’s off the scale I inform the customer there’s a pre-existing problem. Then I normally decline the job unless they want RCBOs fitted. Otherwise you’re only inheriting a major headache that could cause serious grief. My tester cost £70. Best £70 I ever spent. Amcal is the brand. Great video again. 👍

[@learnelectrics4402]

Absolutely right Paul. I never quoted for a job without checking leakage and Zs first.

[@daveroberts832]

Excellent upload as always Dave. Always well presented, informative and clearly explained. Keep it up!

[@learnelectrics4402]

Thank you Dave. Always trying our best and so glad you find the videos useful. Dave.

[@sajad459]

Like always a simple but professional tutorial video, good as Dave. Thank you.

[@learnelectrics4402]

Thanks Sajad. Thanks for the support. Dave.

[@garyplant487]

Another fantastic video. So clearly explained. Dave, you have a knack of being able to teach well. Keep it up please... 👍

[@learnelectrics4402]

Thank you Gary, trying my best, must be the thought of that Spanish wine.

[@Muka-62]

Passed my 18th Edition with you mate managed to hit 80% still learning with you 👍thank you

[@learnelectrics4402]

Thanks for the compliments Trevor. Keep learning something every day, that is the secret. I've been in the game over 40 years and there is always something new to learn. Keep watching, lots more videos on the way. Dave.

[@krzysztofradys7276]

Super wytłumaczone.

[@learnelectrics4402]

Thanks for watching, appreciated.

[@adamoakes3367]

Brilliant tutorials, very clear and easy to understand, well done mate, please keep up the good work.

[@learnelectrics4402]

Thank you Adam, we appreciate your comments. Lots more videos to come. Dave.

[@solomondaniel6149]

Excellent video Dave well planned and explained in a very simple way so anyone can understand the contents and context very well wish you luck and all the best for many more such videos I’m a fan of your videos u r doing a great job

[@learnelectrics4402]

Thanks so much, great feedback. Lots more videos to follow. Dave.

[@krazylad84]

Absolutely marvellous content like always Dave. Looking forward to more videos. Thanks again for the great work ! much appreciated

[@learnelectrics4402]

Glad you are enjoying them and more importantly that you are learning something. Yes, lots more to come. Dave.

[@krazylad84]

@@learnelectrics4402 sometimes electricians change distribution board and afcourse prior tests need to be done before changing but this test can detect earth fault and gives you a clue if the new consumer board will trip or would be a success .

[@christopherblomeley6925]

Crystal clear and practical, many thanks. Christopher. ..

[@learnelectrics4402]

Thank you Christopher, thanks for watching.

[@eldernuru22]

Very educative. You just cleared my doubt on how to carryout a background leakage test. I await more of this kind. Thanks a lot.

[@learnelectrics4402]

Thank you, happy to help. Dave.

[@kingofthetrowel1725]

Been looking forward to this video for a while 👍 brilliant again dave 👌 i now know what earth leakage is 👍👍🙌🏻🙌🏻 absolutley brilliant explanation for a non sparks like myself to understand 👍

[@learnelectrics4402]

That's a fantastic bit of feedback, thank you so much. More videos planned, pass the message on, that's all we ask. Dave.

[@BAYUMBE]

Thank you once again Dave. Very good presentation. It is very illustrated. Very helpful when balancing your consumer unit during selectivity.

[@williamlau7179]

Your video speed & voice is so smooth that I happily finished watching & learning. U r awesome! Thanks for addressing my query of yr earlier video. Just checked my newly purchased smart clamp meter 25$ that the lowest à is 15mA (not good). So, can't measure individual MCB a few mÃ. But still can do the job for main 3-phase rcd. Thank u again for a very professional concise lecture👍🍻.

[@learnelectrics4402]

Nice of you to say so William. Thank you very much. Glad you like the videos and lots more to come. Dave

[@mutawadada6311]

Am absolutely happy i found this channel

[@learnelectrics4402]

Welcome aboard, thanks for watching. Dave.

[@currentsolutions8467]

Brilliant video. Made simple, very simple. Dave you have a brilliant ability in making complicated learning material easy for numties like me. Thanks mate

[@learnelectrics4402]

We were all numties once. Just keep learning and please tell others about our channel. The more that watch, the more videos we can make. Dave.

[@salmanather2125]

Thanks Dave for another fantastic upload

[@learnelectrics4402]

Thank you Salman, always appreciate your support. Dave.

[@smartchip]

Great video, it has been a norm for this guy, thank you,

[@learnelectrics4402]

Thanks for watching and supporting the channel, appreciated. Dave.

[@JIBS.]

Excellent as always. A godsend to anyone coming in to the trade especially trainees/apprentices & those already working within the industry

[@learnelectrics4402]

Thanks for the really nice feedback, appreciated. Lots more videos to come.

[@jonathanwilliams8309]

You are brilliant Dave. And your videos are very helpful 👍

[@learnelectrics4402]

Glad you like them Jonathan, thanks for the feedback. Dave.

[@user-qi8tv2sj4m]

Mate, this is top gold information.

[@learnelectrics4402]

Glad you think so, appreciated.

[@n1kn]

Thank you for another well planned and presented video. You have a outstanding teaching style, and your resources are always a great bridge from your words to my understanding.

[@learnelectrics4402]

Thank you Nik, great feedback. I was lucky that 40 years ago I worked with three outstanding engineers who believed in the learner taking priority. I have copied and improved upon their style ever since. Thanks again. Dave.

[@johnnybuoy9551]

Great Video and Thorough explanation. 1 Question: What if we find a high Leakage Current value? How to resolve it? What are the steps we can take to minimize the already leaking current?

[@learnelectrics4402]

Good idea for another video. Thanks for watching.

[@jeswin501]

Excellent and brillliant explanation 👍

[@learnelectrics4402]

Glad you liked it and thanks for watching. Appreciated. Dave.

[@munafmufc01]

Awsome information thank you so much 😊

[@learnelectrics4402]

So nice of you, thanks.

[@danielteyehuago1633]

Thanks for sharing it with us...

[@learnelectrics4402]

My pleasure, thanks for watching. Dave.

[@30mAkills]

Thanks for enlightenment. I have a Lutron DL-6054 ACA Leakage Tester. I found out that even though meggering value of the circuit is perfect (> 40 megOhms) RCCB nuisance trips. Reason : Megger injects DC voltage in de-energized circuits with all loads disconnected. So it misses leakages of appliances, capacitive leakage of wiring. I read somewhere that the downstream wiring length (from each RCCB) should not exceed 250' length in order to minimise capacitive leakage. So both meters compliment each other. My humble thought.

[@learnelectrics4402]

Thanks for the info. Appreciated and thanks for watching.

[@babyprince84uk]

Thanks a lot! Would love to see a video for clean earthing arrangement and IT rooms arrangement

[@learnelectrics4402]

Noted and thanks for watching. Dave.

[@cemprotecta]

Kudos! Quite informative and practical stuff given here. Thanks

[@learnelectrics4402]

Thanks for the feedback and thank you for watching. Dave.

[@brianhewitt8618]

Excellent Dave , now for the advanced 3ph VD 😊👍

[@learnelectrics4402]

Thanks Brian. You like to keep me busy. Great support, appreciated. Dave.

[@brianhewitt8618]

but its worth it though😊😊👍👍@@learnelectrics4402

[@naturalremediescheshire]

Awesome work Dave, thank you

[@learnelectrics4402]

You are very welcome, glad that you found it useful. Dave.

[@pinchermartyn3959]

Excellent. Many thanks. GREAT learning tool.

[@learnelectrics4402]

You are welcome, your comments truly appreciated.

[@WesleyRSA100]

Fantastic Video 🙏

[@learnelectrics4402]

Glad you enjoyed it, thanks for watching. Many more to come.

[@munafmufc01]

Brilliant explanation thank you so much. Happy New year to everyone

[@learnelectrics4402]

Thanks for watching and Happy New Year to you too. Dave.

[@grantrodgers2829]

This absolutely explained the fundamental aspects. Thank you

[@learnelectrics4402]

Thank you Grant, lovely feedback. Much more to come. Dave.

[@ahsamahi4385]

Thank you for the valuable information thumbs up 👍

[@learnelectrics4402]

My pleasure, thanks for watching.

[@hussmortada]

Thank you once again very insightful.

[@learnelectrics4402]

Very welcome, thanks for watching.

[@johndominguez2290]

I do not who You are, but thank you so much for your help.

[@learnelectrics4402]

Thank you John. A really nice comment and very much appreciated. Dave.

[@mossmm73]

Thanks for your video great benefit for updating an revision

[@learnelectrics4402]

Glad it was helpful and good luck with your career. Dave.

[@swrdashy]

thank you so much for your explanation...

[@learnelectrics4402]

You're most welcome, thank you.

[@Smart-Skippy]

Thank you so much! Great Video!!!

[@learnelectrics4402]

You're very welcome, thanks for the feedback. Dave.

[@vincenthigginbotham8729]

Good advice

[@learnelectrics4402]

Glad you think so Vincent, it makes the effort worthwhile. Dave.

[@davidpatterson1574]

A very understandable explanation, thank you

[@learnelectrics4402]

Thank you for watching, appreciated. Dave.

[@selvaraj8746]

Very much helpful

[@learnelectrics4402]

Glad to hear that, thanks for the comments.

[@RichardFreeman-ke2gz]

Thanks🎉so much.. ..it is very appreciated

[@learnelectrics4402]

Thank you Richard. Dave.

[@BAYUMBE]

Wonderfull lecture as always. Fantastic Dave. Keep it up please.

[@learnelectrics4402]

Thank you Omar, nice feedback. Dave.

[@Golgotasperantei]

Excellent! Thank you very much!

[@learnelectrics4402]

Glad it was helpful and thanks for watching. Dave.

[@shannonj1000]

Hi there great video, I do have a questions, if the RCD on the board is tripping, & won’t reset how would you test, if you are unable to put on a load.. thanks

[@learnelectrics4402]

Turn every breaker off at the CU. Will the RCD reset. If yes, turn the mcbs on one at a time and see if it trips. If it does not trip, turn the breaker off again and turn the next breaker on. Repeat until you find the faulty circuit and then home in on the fault. Unplug everything, reconnect one at a time. have a look at this video on the link. kzbin.info/www/bejne/homukqSVZqmgnbc

[@bharatgurung5848]

Thank you so much for explaining.

[@learnelectrics4402]

My pleasure. Thanks for watching, many more on the channel and lots to come. Dave

[@truthwillout7909]

Very informative, great video

[@learnelectrics4402]

Thank you, great comment. Dave.

[@evanc1721]

Very good! Can I nest RCDs? Like having 3 phase RCD and then an RCD for each phase (so that just 1 phase goes down). Also can I have a lower limit (nested) RCD for the hotub? Last but not least, what will happen to 3 phase appliances if just one phase is interrupted? Many thanks!

[@learnelectrics4402]

Not recommended to have 3 phase equipment protected by single phase RCDs. We should not run 3 phase devices on just 2 phases. Any RCD upstream of another should be less sensitive, a time delay S-type for example to maintain proper discretion, the protective device nearest the fault trips first.

[@30mAkills]

Request to post video on Kirchhoff's First Law or Kirchhoff's Current Law.

[@learnelectrics4402]

Have you had a look at this video on our channel. Click on the link. thanks for supporting the channel. dave. kzbin.info/www/bejne/nnvMoJaagNF7a7s

[@rowles13]

Great video pal.

[@learnelectrics4402]

Thanks for the positive comment, appreciated. Thanks for watching, Dave.

[@konstantinosdm4391]

Great content as always,what about dc leakage? If I have a ac leakage clamp meter do I need to buy a dc leakage clamp meter to measure it?

[@learnelectrics4402]

Yes you can get DC current meters. They work different to AC. Thanks for watching.

[@godfreyssemagobwe4284]

Thanks so much sir for that wonderful explanation please kindly big up.

[@learnelectrics4402]

Thanks Godfrey, glad that you like the videos. Thanks for watching. Dave.

[@yanalnaghawai1872]

Great video as usual, i have a question: Does the leakage current increase the electricity bill ???

[@learnelectrics4402]

Yes it does, its like a dripping tap and a dripping tap will fill a bucket. The customer is paying for electricity that is not going through their appliances. It can be many pounds a year.

[@ibrahimabdullah4430]

Thank you Sir 🙏😊

[@learnelectrics4402]

Thanks Ibrahim. appreciated.

[@evanc1721]

Also, one more question - at my distribution panel it is very hard to use a clamp as all wires are tight. Can I use something with pins (like a multimeter) instead? Many thanks!

[@learnelectrics4402]

No, you are measuring current. If you don't use a clamp meter, you will have to break into the circuit to attach the meter. Can yo find some slack on the wires outside the CU box, it will still be the same current going through.

[@JamesgeraldWard]

Thanks, brilliant

[@learnelectrics4402]

You're welcome, thank you. Dave.

[@Stelyyabs24]

Brilliant vid, Bit confused to how you would test a RCD on the load side with a clamp metre?? As the line is connected via the bus bar??? Only leaving the neutral to clamp around? Can you please explain? Regards Nicholas

[@learnelectrics4402]

Test each MCB output cable individually. Hope this helps.

[@Stelyyabs24]

@@learnelectrics4402 Was thinking along them lines…..Thank you for the confirmation

[@donalfinn4205]

Absolutely tops!👍☘️

[@learnelectrics4402]

Great feedback, appreciated. Thanks. Dave.

[@glennstokes5841]

Thank you very informative

[@learnelectrics4402]

Thanks for the feedback Glenn. It all helps. Dave.

[@gbelectricks]

Great video, how about if you attended for a nuisance rcd tripping. Suppose you carry out an insulation resistance test and all is good. Then you maybe load the circuit up and switch things on and perform another insulation resistance test and again all is good all readings are above well 2M ohm. So say you approach the problem next with an earth leakage clamp meter. So you put your clamp on line and neutral, energise and switch things on then the Rcd trips straight away. How would you suggest to diagnose a faulty appliance with an earth leakage clamp if it trips off too quickly (where IR tests fail to show the fault when the circuit is dead)?

[@learnelectrics4402]

If you know from testing you have a high leakage current and suspect appliances, then unplug everything and retest with clamp meter. One by one plug back in and check leakage reading each time. Sometimes we have even plugged appliances into an extension lead and plugged them into sockets on the other RCD. Let the customer use it for a day or so and see if the problem shifts to the 2nd RCD. Nuisance tripping really is a pain at times. Also, from experience, check EVERY screw in the consumer unit is tight, L/N/E. Make sure you take precautions, live electric. Even a loose screw can cause RCD problems if it shakes. I had one in a pantry and every time they opened the door it hit the CU and tripped the RCD - 4 neutral screws as loose as ever. Good luck. Dave.

[@gbelectricks]

@@learnelectrics4402 these intermittent tripping jobs can be a real challenge to narrow down. It can be a accumulative effect which by itself can be difficult to locate. We had a job recently that showed up as high IR when switched off. Anyway after many return visits to the site we found the problem to be an outside lighting circuit supplying 4x son fittings. When the ballasts got hot it shorted down to earth on 3 out of the 4 fittings. Sometimes you’ve just got to persevere!! Enjoying all your content so far, keep it up 👍

[@30mAkills]

Megger and Leakage tester compliment each other.

[@alextaramsari]

Another great video!! Any suggestions for a good clamp meter with miliohm? Thanks again!

[@learnelectrics4402]

Thanks for the feedback. Clamp meters, we never give recommendations as it can lead to all sorts of horrible situations, but there are at least 4 manufacturers out there that make very very good meters. Get a good meter and it will be your friend for years and years. Thanks for watching and plenty more videos on the way. Dave.

[@dennisfowler7873]

Hi professor D… with todays problems regarding DC leakage into AC circuits which affects ac RCD’s…can a clamp meter measure the dc current….THANKS

[@learnelectrics4402]

Not using the clamp coil Dennis, but one of my clamp meters has separate plug in leads to measure DC current as you would with a multi-meter. Dave.

[@dennisfowler7873]

Thanks…alway searching for an answer…👍👍

[@hussmortada]

Just a question, if each RCD is reading 9mA would we expect the reading at the main switch to be 18mA?

[@learnelectrics4402]

In theory yes, but this will often vary depending on interference patterns. cable resistances etc. At 9mA that is good.

[@hussmortada]

Thank you very much, very helpful as always!

[@garethgordon9141]

How does clamping the line and neutral together determine the earth leakage current? Surely the full current without an earth leakage component needs to be known in advance?

[@learnelectrics4402]

Because the clamp meter will subtract the neutral current from the line current. Any number displayed must be the earth leakage. Hope this helps.

[@jonerasmus9399]

Can any clamp meter work or is it specific to a "earth leakage clamp meter "

[@learnelectrics4402]

Any clamp meter that will show the low numbers that you will be expecting. I use two clamp meters, one in amps for work on big motors and industrial circuits and a second one that will give me milli-amps for leakage tests.

[@proadlekopy]

Awesome

[@learnelectrics4402]

Glad it helped.

[@Dog-whisperer7494]

Can any clamp meter be used to measure earth leakage? Excellent video thank you

[@learnelectrics4402]

Any clamp meter but as we say in the video, Sean, it is best done with a meter with a mA range. I have one with milliamps, which is great, and it will show readings less than 1mA, but the 2nd meter, the bigger 400 amp clamp meter shows most small readings as zero as it won't range down to little readings. Horses for courses. Dave.

[@Dog-whisperer7494]

@@learnelectrics4402 thank you that’s a big help I may have to buy a new clamp meter

[@johnmangcao5793]

Does this earth leakage current adds to electric bill or increase it? Thanks

[@Webbster77]

BRILLIANT EXPLANATION

[@learnelectrics4402]

Thanks Tony. Feedback always appreciated. Dave.

[@MultiOutdoorman]

And re-label the re-located circuits too ! Cheers

[@learnelectrics4402]

Absolutely, thanks for the input. Dave.

[@davidwingrove7004]

BS 7671 or the latest edition of the “Wiring Regulations” are not mandatory they are a code of practice. Compliance with them will almost certainly satisfy the Electrical at Work requirements which are mandatory.

[@learnelectrics4402]

Absolutely, that;s why I always advocate compliance. Thanks for watching. Appreciated.

[@Stile30]

I understand why you need to keep everything turned on when checking leakage on RCD. But why you said that all MCBs need to be turned off except one which is measured? I assumed when measuring MCB leakage current that also all other MCBs are turned on to simulate real life. Please, explain?

[@learnelectrics4402]

If you want to check leakage on just one MCB when tracing problems then you need to turn the others off to stop them affecting your readings. You are trying to narrow down your search area to pin point the problem.

[@Stile30]

@@learnelectrics4402 thanks for your fast reply. I understand but I think that other MCBs will not affect on differential current on measured MCB when other MCBs are ON. Leakage on certain MCB will be same whether other MCBs are ON or OFF. Or I am completely wrong?

[@webber977]

new sub for you Dave been trying to sort an intermittent trip problem , was thinking of hiring an exorcist ,but checking for earth leakage may be a better option , cheers mate

[@learnelectrics4402]

These problems are a devil to find. Patience and notebook about each change you make are helpful. Good luck. We are planning a video soon just on intermittent tripping. Bet you've got it sorted before then. Dave.

[@surujzaman2294]

good morning, how are you sir,

[@learnelectrics4402]

I'm good. Thanks for watching.

[@lekgadimanemasegare3095]

I WANT TO WRITE A TEST BUT IM 68YEARS OLD HOW CAN I DO

[@learnelectrics4402]

Not sure which test you want to take. Contact a local training centre and they will guide you through the various test options, learning packages available. Good luck.

[@tzm1843]

Excellent! Thank you!

[@learnelectrics4402]

Glad it was helpful and thank you.