LIGHTING CIRCUIT FAULTS FOR ELECTRICAL ASSESSMENTS and FAULT FINDING

We have often been asked about the type of lighting faults that you might be expected to find during an electrical assessment. And we have also been asked about the types of faults to expect in installations of a certain age.

Not surprisingly, they are pretty much the same faults and it should be within the capabilities of everyone to find these during an inspection and test on an actual installation or during an electrical inspection and test assessment.
In the domestic world, lighting circuit faults are common and we will show you some of these in this video from LearnElectrics.

This video is No.142 on our YouTube channel where we have videos on a wide range of electrical topics.

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Always work safely, electricity can be dangerous. If you are unsure, stop and seek advice.
This video is provided for guidance only. Every electrical situation is different, please check and ensure that you are applying this learning information to your own individual circumstances correctly and safely. If in doubt, stop and seek competent advice.

[Anonviewer]

3rd year apprentice here, very helpful video, I wish this was explained to me in this way when I first started as this would have been a catalyst to my learning. Thank you.

[danielteyehuago]

Watched it thrice for a deeper understanding... Asking questions takes you directly to problem easily...

[jmohammad]

Absolutely brilliant video typical and common faults which you will find on a daily basis when being called out to fault finding on luminare circuits. Nicely explained and very methodical method which I follow. Thanks Dave keep these great video's coming much appreciated and wanted.

[BasebossSports]

Amazing video honestly. Clear and simple to understand. Thank you for this video. It has helped me loads!

[danielteyehuago]

Wow! This is very informative, thanks for sharing it with us Dave. It worth it and the best tutorial on the topic for me.

[AngelaPeters-fytc]

Hi Robert here not Angela lol, another excellent video especially the large easy to follow diagrams. One thing though am i correct in saying that on a1 way light switch the brown live wire on the switch cable terminates in the common but on a 2 way or 3 way lighting configuration that same brown wire terminates in L1 and the black strapper cable from the 3 core goes into the common and also either gets carried on through to the common on the either 2nd or 3rd switch depending on the set up. Its remembering this which is tricky i guess it comes with practise thankyou so much your videos are a godsend they really are.

[NurCanastel]

Thanks for your help very well explained best tutor thanks

[seandempsey]

Fantastic video Dave as always 👍 I have come across most of these faults at some point in my career. Mostly as a result of DIY . I don’t see them at all these days. Maybe that’s a sign the DIYers are leaving the electrics alone and sticking to putting shelves up .
Thank you you reminding me with another good brain work out.👍👍❤️

[three-phase]

Very good video, well thought out scenarios thoroughly explained by the graphics in an easy to follow manner.

[EdwardBretherton]

awesome videos Dave, they all help fill up the knowledge, how about a video or two on prep for lvl3 exams on all subjects

[MMG_MoonManGuitar]

Another great video. Always good for refresher training. Thank you as usual mate.

[ahmadtareqslamzadeh]

Thanks again for your very helpful video.

[BelajarBaik]

It's a very interesting review.☺☺☺

[MS-Patriot]

I have found the trapped insulation problem and loose terminals within pre wired connector blocks on outdoor lighting accessories from the well known DIY suppliers. Check all screw connections, saves getting the ladder out twice!

[mohammadshirifeshki]

Thank you Dave. I have got a question about insulation resistance test on lighting circuit. When there is so many spotlight oncircuit, some electricians do the test bu 250 rather than disconnecting all light and doing 500v test. Some connecting line and neutral and just doing test between them and earth. Is it right way?
Does it comply with regulation?
Sorry if you find it irrelevant question.

[no_short_circuit]

Thanks again for the video. I may be wrong here, but at 3.09 you say "the current flows through the switch to the common terminal and up to the switch block". Your diagram shows the switching line coming from L2 to the switch block?

[zippymo]

I did a lighting circuit fault find 2 weeks ago. Customer complained of a burning smell and coming after he switched on the lights and then the lights tripping.

After a few investigation we lifted up a floorboard to get acces to a joint which I couldn't get to from the light fitting, and saw a huge rat had clamped onto the switch wire. The burning smell was the rat cooking when the current was flowing through him. There were also live maggots eating him out 🤢🤢🤢🤢.

[KM-zmiy]

Thank you Dave for the detailed explanation. If possible, I can communicate with you to discuss some questions related to street lighting circuits, as I have been working in this field for a long time and I face some technical problems due to the inability to understand how to choose the appropriate method to protect these circuits and people from electrical hazards. One of the problems is, if the luminaires are LED type and feed by a 3phase (4by16mm2) cable system. Is it ok or not to use the armor of the (4by16mm2) cable as a cpc instead of a copper cpc to reduce the cost of materials?. The second question: is it a must to use an RCD in addition to the circuit breaker in these circuits?

[chalakfaris]

can you make a video about testing motor in circuit

[michaelrichard]

How would you fault find the neutral cable in the wring rcd fault