To view a list of all our LearnElectrics videos, click on the link below. There are many videos on many electrical topics including Installation, Part P, 18th Edition, Testing, Certification, Lighting, Sockets, Ring Circuits and much more. ua-cam.com/channels/YaJQnpO4XAp0yCgqzMkmfA.html
Hello, Starting course in September , just trying to learn some basics before hand , and this was very useful to watch . Thank you so much time well spent and was well worth it . Please keep up the great work 🙏.
Thank you Roslyn, great feedback. The videos are aimed at new starters like yourself. Tell your college friends, the more people that watch the videos, the more we can make. Good luck with your apprenticeship, it really is a good trade to be in. Learn a little bit every day, it all adds up to great knowledge. Dave.
Excellent content like always Dave. Even though the concept looks pretty easy but there is always something new to learn in your videos. Much appreciated thanks
Thanks for the positive comments. Our approach is to show just one concept or piece of information at a time - one theme, one video, rather than go into information overload. Glad you enjoy the videos, there are lots more to come. Dave.
Another excellent instructional video from Learn Electrics - thanks. Where do you get the slide images from ? They are so clear and explain exactly how the RCD works - I've not seen anything so comprehensive and at the same time concise. Did you draw them yourselves ?
All my own work and thanks for the compliment. At the end of the day I want people to learn, so a good drawing is essential. Thanks for watching. Dave.
Sir, to us you are a very knowledgeable person and a excellent teacher.Thank you for sharing your knowledge with us 👍.Q:My house often trip when there's a even a slight lighting strike or indirectly (EMI). Can I install RCCB Auto restart device and how to wire it up? Thanks
The idea of an RCBO/RCD in domestics is that it dead trips and doesn't reset Might I suggest that you check what the earth leakage is with a clamp meter on a good day. You may find it is already around 15mA and all RCD devices can trip anytime after 15mA, usually around 22mA. Not at exactly 30mA as many think. Hope this helps. Dave.
Anything to make life easier Andy. We used to change the batteries in the smoke alarms at Xmas, an easy time to remember. We've got 10 year batteries in now, still working out a memory jogger for that. Hope you are keeping well, we all deserve a curry night out when this covid is over.
thanks for the wonderful video, my new apartment RCDs for newly installed Shower Heater kept tripping as soon as the 4 pole heater switch is switch on, brand new shower heaters were installed correctly. Suspecting wiring mistake done by the apartment builder. Can you advise any clue or step-by-step guide to diagnose this issue? thanks in advance!
Could be lots of things Alan. My first thought is neutral wires in the wrong RCD. Put the RCD to ON with all the power to the shower set to OFF, and the switch to OFF Then turn the shower switch ON. If the RCD trips immediately (the same instant in time), especially if it is both RCDs that trip, then it could be that the Line for the shower goes to one RCD and the Neutral goes to the other RCD. This is an imbalance. Get the sparky to come back and put the Neutral into the other Neutral bar so that Line and Neutral are on the same RCD. Hope this helps, Dave.
Thank you. Very simple and concise! I have an ATS system switching between my off-grid installation and company power based on my battery bank voltage and off-peak tariff but when I am pulling >2kw often my main panel RCD trips...not sure what might be causing it. Any ideas? Thank you!
If you have lots of devices plugged in and each has a few mA of earth leakage, you will reach a point where they all add up to 25 to 30 mA and the RCD will trip. The good way is to unplug everything and plug in items one at a time until it trips. If it trips with the same item each toime that could be the problem. Try running the same items but spread across two RCDs. Good luck. Dave.
@@learnelectrics4402 Thank you Dave. This is inline with my experience. Unfortunately it will be difficult to divide loads between RCDs on the main panel due to lack of space. I guess I have to forget the ATS automation and have the switch between offgrid and company mains on a manual fashion with few loads on.
My humble suggestion: The inbuilt test button can only assure that the electromechanical trip mechanism which consists of multiple moving components such as springs, levers, pivots, pins, links and cams are working properly. This cannot tell you the trip time. So I test rccb once a year with third party tester and note the trip time which should not exceed 300 millisecs.
Good question Chris. The whole point of voltage drop calculations is that you don't have the circuit so long that the volts drop exceeds the maximum permitted. If you need longer circuits and still need the same load, you may need to increase the cable size and do the calcs again. Longer circuits are more likely to reduce tripping as the resistance has increased. Hope this helps. Dave
No. But they both did similar jobs. An ELCB - Earth Leakage Circuit Breaker is a voltage leakage detecting device. These have/are being replaced by RCDs Residual Current Devices that detect current leakage. Generally, RCDs give better protection to humans and animals.
where does the leakage current go if there is no earth, like in older lighting circuits for example? What would happen if you borrowed a cpc from a nearby socket as a less disruptive method of earthing circuit? Would this just mess up the earth fault loop impedance? Thanks
Leakage current will go by whatever path it can find, extraneous metalwork, people, wherever it can get. Trying to eliminate leakage is a preferred option rather than using other circuits. each circuit should have its own earth if required. Dave.
Thank you again for a very clear explanation. Would it be possible to do a video on how DC saturation of the coil interferes with the RCD operation? I'm an adult learner and can't get my head round that.
Don't try and overcomplicate things, the important thing is to fit the right type of RCD and we have that on our list for a video. Just think of saturation as measuring the rise and fall of water in a bucket that is half full - easy. Now try and measure the rise and fall if the bucket is full to overflowing, saturated. You can't really see a change if everything is spilling over. Does this help? Dave.
We do residual voltage tests to detect any residual voltages in electrical equipment/electronic cabinets that are still present in the circuits after the main source has been isolated. A safety verification. Not the same as RCDs. Dave.
Sir is that mean the RCD is a requirement in TN systems too ? I am living in TT grounding country. For TN systems will there be any problems of unwanted tripping of RCD due to earth and neutral voltages ?🙏 And thanks for the video s.👍
Nice one dave well explained again 👍👍👌👌 are you still going to do an earth leakage video , on why it does it and how etc I know it’s briefly mentioned in this video but would like to see more on the topic to understand 👍👍
Just to keep you in the loop. Thursdays video is on device selection, switches, breakers and RCDs Then, next week is a video on Earth Leakage Measurements. Dave
There are some old buildings without earthing and bonding, I guessed using RCD would be some help in these cases, but bs7671 forbids using them in TNC systems. Do you have any idea why they say this? I know that it wont be a perfect protection but at least RCD will improve the safety of that old buildings.
@@learnelectrics4402 Yes they can't solve the fault when it happens, but at least when someone touches the body of electrical equipment, RCD would survive him. Without RCD, he will die. When BS7671 forbids it, that seems similar to saying : If your car does not have a healthy brake system, you are not allowed to install airbags :)
If the line and neutral are the same, or within limits, the RCD will not trip. If there is leakage N to E then it won't take much to make it trip. Take a ,look at this RCD testing video ua-cam.com/video/PXKaq_1DmgU/v-deo.html
@@learnelectrics4402 thanks for the reply👍. Normally an earth to neutral will imbalance the rcd causing it to trip correctly, as in 99% of cases. I assume the fault i had ( neutral to earth dead short) would & should trip the rcd, but in a couple of fault finding missions, the rcd was blinded somehow!! I can only assume that the earth was at the same potential as the neutral, thus the rcd didn't trip. I can assume that the main earth was not efficient in the dwelling.
That's not how RCDs work. If you have another look at the video you will see that the RCD looks for a difference between in and out currents in the phase and neutral.
Very similar. The three phases are 120 degrees apart so the difference between all three phases should be what is in the neutral. I might include 3 phase RCDs in our soon to be finished video on RCDs. Good question.
To view a list of all our LearnElectrics videos, click on the link below.
There are many videos on many electrical topics including Installation, Part P, 18th Edition, Testing, Certification, Lighting, Sockets, Ring Circuits and much more.
ua-cam.com/channels/YaJQnpO4XAp0yCgqzMkmfA.html
I know how an RCD functions, but they way Dave explained it is magical and has given me more of an indepth understanding. Thanks again
Thanks for the great comment. Really appreciated and lots more to come.
I’m not an electrician but would love to learn more. This video was really helpful and digestible, thanks a lot!
Glad you enjoyed it and thank you for watching. Dave.
Hello,
Starting course in September , just trying to learn some basics before hand , and this was very useful to watch .
Thank you so much time well spent and was well worth it .
Please keep up the great work 🙏.
Glad it was helpful, lots moire to come. Spread the word. Dave.
I love these videos - I have recently started as an apprentice and the short, concise and clear explanations of concepts are invaluable. Thank you!
Thank you Roslyn, great feedback. The videos are aimed at new starters like yourself. Tell your college friends, the more people that watch the videos, the more we can make.
Good luck with your apprenticeship, it really is a good trade to be in. Learn a little bit every day, it all adds up to great knowledge. Dave.
thank you sir, your animation & picture help me alot to understanding about the electrical work! i LOVE the way you teaching. God Bless U
You are very welcome, happy to help. Thanks for watching. Dave.
The best explanation ever watched on this subject
Thank you very much, appreciated.
Excellent content like always Dave. Even though the concept looks pretty easy but there is always something new to learn in your videos. Much appreciated thanks
Thanks for the positive comments. Our approach is to show just one concept or piece of information at a time - one theme, one video, rather than go into information overload.
Glad you enjoy the videos, there are lots more to come. Dave.
Thank you, sir. I was having a problem understanding how rcd works and now I'm not afraid to write my test today no more😁
Brilliant. Glad it helped and thanks for watching.
Very good explanation im understanding better now
Glad it helped, thanks for watching.
@@learnelectrics4402 I will continue to watch
RCD saved my life today. Thank you Henri Rubin and Charles Dalziel
Brilliant that you are here to tell the tale. Hopefully you learnt where things went wrong. Dave.
Another excellent instructional video from Learn Electrics - thanks.
Where do you get the slide images from ?
They are so clear and explain exactly how the RCD works - I've not seen anything so comprehensive and at the same time concise.
Did you draw them yourselves ?
All my own work and thanks for the compliment. At the end of the day I want people to learn, so a good drawing is essential. Thanks for watching. Dave.
This one, as with the others, was perfectly explained…..
Thanks Joel, great feedback. Dave.
Great video.
You are always a game-changer.
We appreciate your efforts.
I appreciate that, thanks.
Sir, to us you are a very knowledgeable person and a excellent teacher.Thank you for sharing your knowledge with us 👍.Q:My house often trip when there's a even a slight lighting strike or indirectly (EMI). Can I install RCCB Auto restart device and how to wire it up? Thanks
The idea of an RCBO/RCD in domestics is that it dead trips and doesn't reset
Might I suggest that you check what the earth leakage is with a clamp meter on a good day. You may find it is already around 15mA and all RCD devices can trip anytime after 15mA, usually around 22mA. Not at exactly 30mA as many think. Hope this helps. Dave.
@@learnelectrics4402, Thanks you Sir I will try rectify the problems.🙏
the best possible explanation thanks.
You're welcome and thanks for watching.
Great video information 👍❤, please make a video information for LATCHING RELAY.
Ok coming soon, I've put it on the list. Thanks for watching, appreciated.
This is good mate. More like this please.
Lots more to come. Dave.
Good video mate. Retired 16th edition.
I started with 14th. How things have changed.
Best ever. Very very informative. Thanks a lot
Glad it was helpful and thank you for watching. Appreciated.
This is Awesome thank you for sharing this.
Very welcome Patrick. Lots more to look at and lots more to follow. Cheers. Dave.
This vid is brilliantly clear and direct 👍👍👍
Glad you think so Stephen, appreciated,
@@learnelectrics4402 (I say it as a non-electrician who understood every word.)
Great sugestion of the Clock change test schedule Mr B :)
Anything to make life easier Andy. We used to change the batteries in the smoke alarms at Xmas, an easy time to remember. We've got 10 year batteries in now, still working out a memory jogger for that. Hope you are keeping well, we all deserve a curry night out when this covid is over.
@@learnelectrics4402 Absolutely mate! Its been far to long!!
Too true Andy.
really appreciate all the content! massive help at level 3!
My pleasure, everything we can do to help make it all worth while. Dave.
Great video
Thanks for watching, appreciated, Dave.
thanks for the wonderful video, my new apartment RCDs for newly installed Shower Heater kept tripping as soon as the 4 pole heater switch is switch on, brand new shower heaters were installed correctly. Suspecting wiring mistake done by the apartment builder. Can you advise any clue or step-by-step guide to diagnose this issue? thanks in advance!
Could be lots of things Alan. My first thought is neutral wires in the wrong RCD.
Put the RCD to ON with all the power to the shower set to OFF, and the switch to OFF
Then turn the shower switch ON. If the RCD trips immediately (the same instant in time), especially if it is both RCDs that trip, then it could be that the Line for the shower goes to one RCD and the Neutral goes to the other RCD. This is an imbalance. Get the sparky to come back and put the Neutral into the other Neutral bar so that Line and Neutral are on the same RCD. Hope this helps, Dave.
Very clear explanation. Thank you.
Thanks for watching, glad you found it helpful. Dave.
Beautifully explained . Bravo
Thanks. Glad you liked it. Lots more to come. Dave.
Would it be a problem if a socket with RCD protection was put onto a circuit already protected with an RCD at the board?
No, except which one goes first? We are doing a video on RCD discretion soon.
Wow! This is very informative, thanks for sharing it with us. It worth it...wtc
Our pleasure Daniel. Keep watching, some good stuff coming up. Dave.
Thanks very much for this video ,it is vey clear and understandable
Glad it was helpful, lots more to come. Dave.
EXCELLENT PRESENTATION!😃
Thank you Trevor, appreciated. Dave.
Great tutorial. Thanks a lot .
Thanks Antonio. Dave.
Thank you. Very simple and concise! I have an ATS system switching between my off-grid installation and company power based on my battery bank voltage and off-peak tariff but when I am pulling >2kw often my main panel RCD trips...not sure what might be causing it. Any ideas? Thank you!
If you have lots of devices plugged in and each has a few mA of earth leakage, you will reach a point where they all add up to 25 to 30 mA and the RCD will trip. The good way is to unplug everything and plug in items one at a time until it trips. If it trips with the same item each toime that could be the problem. Try running the same items but spread across two RCDs. Good luck. Dave.
@@learnelectrics4402 Thank you Dave. This is inline with my experience. Unfortunately it will be difficult to divide loads between RCDs on the main panel due to lack of space. I guess I have to forget the ATS automation and have the switch between offgrid and company mains on a manual fashion with few loads on.
Very well explained. Thank you.
Glad you liked it, thank you.
Thank you
You're welcome, thanks for watching. Dave.
Great vid thanks
Glad you enjoyed it, thanks for watching.
My humble suggestion: The inbuilt test button can only assure that the electromechanical trip mechanism which consists of multiple moving components such as springs, levers, pivots, pins, links and cams are working properly. This cannot tell you the trip time. So I test rccb once a year with third party tester and note the trip time which should not exceed 300 millisecs.
This is exactly what it says in Section 11.6 of the OSG, page 129. Some good information if you have a look; and thanks for watching.
Thanks Dave, you have a talent for these videos
Keep up the great work !!
Nicely explained. Thanks. 👍🙂
Thanks, great feedback and appreciated. Dave.
Thank you Good Sir for sharing your valuable knowledge 🙂. Subscribed and look forward to viewing your videos.
Thank you Mophammad, thanks for watching. there are nearly 200 videos to watch, and growing. Dave.
what about voltage drop on long circuits. Could this lead to unwanted tripping
Good question Chris. The whole point of voltage drop calculations is that you don't have the circuit so long that the volts drop exceeds the maximum permitted. If you need longer circuits and still need the same load, you may need to increase the cable size and do the calcs again. Longer circuits are more likely to reduce tripping as the resistance has increased. Hope this helps. Dave
This guy is a legand
Wow, great feedback. Thank you, and thanks for watching. Dave.
I'm so amazed of your video's, but i still confused, are RCD's and ELCB the same? thank's before
No. But they both did similar jobs.
An ELCB - Earth Leakage Circuit Breaker is a voltage leakage detecting device.
These have/are being replaced by RCDs Residual Current Devices that detect current leakage. Generally, RCDs give better protection to humans and animals.
Can you do a quick video explaining the difference between a passive rcd, and an active rcd? - or if easier in answer to this question
A few people have asked for more on RCDs, its on the list. Thanks for watching. Dave.
where does the leakage current go if there is no earth, like in older lighting circuits for example? What would happen if you borrowed a cpc from a nearby socket as a less disruptive method of earthing circuit? Would this just mess up the earth fault loop impedance? Thanks
Leakage current will go by whatever path it can find, extraneous metalwork, people, wherever it can get. Trying to eliminate leakage is a preferred option rather than using other circuits. each circuit should have its own earth if required. Dave.
@@learnelectrics4402 agreed but when rewiring is not an option would using another circuits earth be better than no earth?
Which side does the supply cable enter on a three phase rcd, top or bottom?
If its marked 1 - 3 - 5 then those are the inputs and 2.4.6.the outputs. Hope this helps. Dave.
@@learnelectrics4402 thanks,does that sequence protect the test button if it's held for too long?
Thank you again for a very clear explanation. Would it be possible to do a video on how DC saturation of the coil interferes with the RCD operation? I'm an adult learner and can't get my head round that.
Don't try and overcomplicate things, the important thing is to fit the right type of RCD and we have that on our list for a video. Just think of saturation as measuring the rise and fall of water in a bucket that is half full - easy. Now try and measure the rise and fall if the bucket is full to overflowing, saturated. You can't really see a change if everything is spilling over. Does this help? Dave.
@@learnelectrics4402 Thank you for your prompt reply. What video on your playlist covers selecting the correct type of RCD?
We've not done that video yet. A few have asked so we'd best pull our finger out. Thanks for the interest in our videos. It won't be long.
You’re the best !
Well thank you very much Masoud, brilliant, please tell others about the channel. Thanks for watching, lots more to come. Dave.
What is a Residual Voltage Device?
We do residual voltage tests to detect any residual voltages in electrical equipment/electronic cabinets that are still present in the circuits after the main source has been isolated. A safety verification. Not the same as RCDs. Dave.
Sir is that mean the RCD is a requirement in TN systems too ? I am living in TT grounding country.
For TN systems will there be any problems of unwanted tripping of RCD due to earth and neutral voltages ?🙏
And thanks for the video s.👍
If installed correctly then no problems. In the UK we must install RCD devices in domestic dwellings. Thanks for watching. Dave.
Nice one dave well explained again 👍👍👌👌 are you still going to do an earth leakage video , on why it does it and how etc I know it’s briefly mentioned in this video but would like to see more on the topic to understand 👍👍
Yes, its intended to include it in the next RCD video - choosing types of RCD as these replaced ELCBs. Thanks for the great comments. Dave.
Just to keep you in the loop.
Thursdays video is on device selection, switches, breakers and RCDs
Then, next week is a video on Earth Leakage Measurements. Dave
@@learnelectrics4402 brilliant stuff , I really do look forward to watching them 👌👌 cheers dave thank you 🙌🏻🙌🏻
You are very welcome, thanks for the positive comments.
There are some old buildings without earthing and bonding, I guessed using RCD would be some help in these cases, but bs7671 forbids using them in TNC systems. Do you have any idea why they say this? I know that it wont be a perfect protection but at least RCD will improve the safety of that old buildings.
You need a separate earth for RCDs otherwise they can't tell there is a problem.
Hope this helps. Dave.
@@learnelectrics4402 Yes they can't solve the fault when it happens, but at least when someone touches the body of electrical equipment, RCD would survive him. Without RCD, he will die. When BS7671 forbids it, that seems similar to saying : If your car does not have a healthy brake system, you are not allowed to install airbags :)
How does a neutral to earth fault stop an rcd functioning correctly? I've had this problem a couple of times , normally it would trip the rcd !!!
If the line and neutral are the same, or within limits, the RCD will not trip. If there is leakage N to E then it won't take much to make it trip. Take a ,look at this RCD testing video
ua-cam.com/video/PXKaq_1DmgU/v-deo.html
@@learnelectrics4402 thanks for the reply👍. Normally an earth to neutral will imbalance the rcd causing it to trip correctly, as in 99% of cases. I assume the fault i had ( neutral to earth dead short) would & should trip the rcd, but in a couple of fault finding missions, the rcd was blinded somehow!! I can only assume that the earth was at the same potential as the neutral, thus the rcd didn't trip. I can assume that the main earth was not efficient in the dwelling.
Can a RCD detect a external fluctuating current that is entering the property from say a main water pipe?
That's not how RCDs work. If you have another look at the video you will see that the RCD looks for a difference between in and out currents in the phase and neutral.
@@learnelectrics4402 but what if the fault is before the rcd?
RCDs work on faults downstream of them.
@@learnelectrics4402 is there any way an upstream fault can be detected though, maybe intermittent tripping?
you're a perfectly youtuber
Thank you Jordan and thanks for watching. Dave.
Great
Thank you. Lots more to come. Dave.
Can explain how a three phase RCD works?
Very similar. The three phases are 120 degrees apart so the difference between all three phases should be what is in the neutral. I might include 3 phase RCDs in our soon to be finished video on RCDs.
Good question.
Drawing, ie DRAW-ING and NOT "DRAW-RING".
Thanks for watchring.
That kettle will save you ten pounds a year, every year on your electricity bill
Its all about energy saving now Ryan, thanks for watching.
konnte mir des jz nich so gut merken
ich hoffe du erinnerst dich jetzt. Thanks for watching, lots more to come. Dave.