Thanks for a clearly explained video. Just a point to remember when referring to a six millimetre cable it refers to the cross sectional area of the copper and not the diameter of the copper wire. Back when I started in home renovation, I would measure the copper wire with a vernier and then wonder why 6 mm was not the diameter ? Of course not - 6 mm refers to the area - it should be written 6 mm2.
Interesting. I hadn't realised just how much running cables through insulated walls makes to the amperage rating of the cable. It's definitely, something to keep in mind when adding insulation to existing walls, ceilings etc.
I am an electrician ,and on cookers you should allow for diversity , this is an allowance in the electrical ie regs, that means you would never have the cooker on full load ,talking the full 10kw while cooking ,( every oven and ring on full power) this means a 32A CB would be OK with 4mm cable for a short run and 6mm for a long run of cable.
Thank you very much for your clear instruction and for following the regulations guidelines. I hope you can do much more youtubes about this subject. I have learnt lots from this.
I like this simple approach to calculating the design. I can't see a problem with using cable that's over-rated at is has less resistance and can cope with future changes to circuit usage. Diversity is an optional consideration if you don't want to spend too much on cabling etc. but it takes no account of future usage, so having larger cables is fine if you want to pay for it.
What do you mean take the "diversity" into account? Is that the tollerance of the cable? O you mean 1 usage of voltage between L1 and L2 ? He choose 230 Volt and that is between L1 and Neutral, so there is no square 3
Hiya. I'm enjoying your videos Buddy. Just thought I'd mention it, as you did choose to use a cooker as your example. Don't forget to apply diversity as it is highly unlikely to ever reach its maximum demand due to the thermostats in the cooker rings. In your example (44 A) it would be the first ten amps (10 A) then 30% of the remaining amps (approx. 11 A) PLUS 5 A if there's a socket outlet on the cooker isolator. So, your 44 A has gone down to 26 A. The next MCB up from that is a 32 A. I'd still use 6mm cable though.
Kevin McNicholas I've always been told to use 10mm by my boss..I suppose this would save money if working for yourself.. I've recently sat the 2391-52 exam,no one could give me a exact way too work out maximum demand/ diversity nt even in bs7671 book
cater4anytink Yeah, I know what you mean. I suppose it would be useful to if the oven was ever upgraded again. It's a trade off though, isn't it? If customer wants to pay for cable that is far and away able to deal with the demand, fair enough. Thing is though, why don't we do rings in 4mm instead of 2.5mm? Because of cost, that's why. And if your wiring a lot of houses that's going to be a lot of wasted money. If customer is willing to pay the extra i.e. maybe £45, let's say, instead of £30 then yes, do it in 10mm. Diversity is covered in the On-site guide.
cater4anytink checkout the best sparky in the U.K. he knows the regs in his head, can tell you the reg and the page its on, his name is john Collins, his training place is in dudley West Midlands, he is a great trainer, he used to teach at sbc college, he teaches in small groups, like two! On different meters, as everyone has different meters, etc, everyone knows him, especially the regs guys, ex military,
smartchip John Collins? Ha, ha... you mean 'Johnnie Ace'!! Oh, he's great. I love watching his vids. Very knowledgeable and puts things over in a way anyone can understand. Johnnie Ace, (tsk,tsk), is on the case. That's a great catchphrase. 👍🏼
Howdy. Nice presentation of rating the thermal overload case. There is, however, another equally important aspect. The short cicuit case. There must be enough "short force" feeding the breaker to enable fast breaking (=magnetic triggering) of the breaker. In my location the power companies will provide information of how much short current is available at the service cable junction. From this point forwards one must calculate the short current at the most distant appliance or socket and choose a breaker that will fast trigger. If the short current is too low to deliver fast triggering the short current will flow until the thermal breaking happens. The socket wiring will run way too hot and there is a real fire hazard present. Regards.
A very simplistic look at the cooker circuit, you need to take diversity into account as the load is thermostatically controlled and therefore wouldnt pull the full load all the time.
This is quite a broad topic. You managed to explain the most important parts, excluding the formulae. For heavier loads we (central Europe) usually use 3 phase circuits.
Most of the domestic-houses here DO use 3 phases + neutral. AC Voltage LN 230V, LL 400V, main fuses are 3 x 25A or 3 x 20A and current limiters inbuilt in the electrical power meter. Electric stove usually uses 3 phase, so does the heat pump, and other various bigger loads.
at 1:15 talk about cable size 6mm, 2.5mm and 1.5mm. Iit should be read as 6mm square, 2.5mm square and 1.5mm square instead. Many thanks for this video!
One thing to remember regarding cookers... If it is a three phase connection than that 44 is divided by 3, which means you can connect each of the phases separately and the cable size does not have to be bigger than 2.5mm and size of three breakers collectively has to be 20 Amps each (44x1.25=55÷3=18.33)
After waiting two weeks for a new cooker from a place that has the same name as a god, I paid for it to be put in. A bit more than £100. They said they could not do it. That I can only have a cooker thats 20 amp. I did not watch them try. My lights went off and on many times. So I went to see what the hell was going on. My fuse box says 32A . I have to wait 30 days to get my money back.
You have explain the calculation to obtain circuit breaker amp size and from there, select the cable size based on the table. But, I am curious about the calculation to obtain wire size. Why using 1.5 cable for ac for for example can cause it overheat. What is the maximum by calculation for current to pass through wire certain size.
Thank you for a very good presentation. I am quite stunned about the wire size. Here in Denmark for a cooker it would be 3 phase and 400 V. The calculation would be like this: 10000 W / 400 V x 1,73 (square 3) = 14,4 Amps This will eventually lead to a 2,5 mm2 if it is not placed to hot. Quite a difference! It would be fused with a 3 phase 16 amp.
@@mortenlund1418 But that cooker should allow a 3 phase connection? In the video he defined a 10kW cooker that works on L1 and neutral, other people mention "diversity factor" What is that?
Thank you for yoir explanation, I only have one note: When you get the current you divided power over voltage without the power factor.. it should be P/(V*pf) so the current will be 48 A , then you should select a cable size according to that.
You forgot to take into consideration diversity, so take the first 10A and 30% of the remainder = 10 + 11.33 = 22.4 A approx , so theoretically 2.5mm would suffice if on a type B circuit breaker, 4mm to be safe. ( 6mm cable comes from the old days on semi enclosed fuses - where the correction factor pushed up the requirement for a larger cable)
You have to assume that not all the burners and oven etc in the cooker will be on at the same time and draw full current. So we diversity meaning an average current that would be use so 10000/230 = 47amps,take 10amps out will leave 37.then you have to take 30% of 37 which is around 10 or 11 and add back the 10amps that you took earlier and will give you around 21amps. In this way you can use 32amps mcb and a lower siZe cable.
@@septin2008 I think Diversity is ONLY used to calculate the overall current demand of current in the house to see if the demand goes over 60 or 100 Amps etc. If you you diversity for calculating MCB and cable size, you would end up tripping MCB whenever you use the full load (xmas cooking etc) or if you had a bigger MCB but a small cable, then cable will burnt down when full load is used......
i now 1mm cu wire can hold max 8 amp without voltage drop 0.05% in lenth 100 meter and don't get hot so (1mm 8amp) , (1.5mm 12amp) , ( 2.5mm 20amp) , (4mm 32amp) , (6mm 48amp) , (10mm 80amp) , (16mm 128amp) and thanks for your great video.
hold on , you should also take in to account the method of installation , the various conditions it will pass through (example , you may go through insulation and then into free air which operate at different temperatures
Good Morning! Nice work! Three things here, 1. You didn't consider power factor (cos theta) 2. What is the phase (single or 3-phase)? 3. Please,what is the name of the handbook and how & where can I get an electronic copy?
its called On-Site GUIDE ,make sure buy the 18th Edition and you can find the all info and installation method about wiring.www.amazon.co.uk/Site-Guide-7671-Electrical-Regulations/dp/1785614428/ref=sr_1_1?ie=UTF8&qid=1543285293&sr=8-1&keywords=18th+edition+on+site+guide
1 amp equals 1 coulomb of electrons. The NUMBER of electrons in the cable is limited by the diameter of the cable. Very informative video. Are the lamps in the "cooker" the same voltage as the heating coil?
Could I ask you to do a video on led out side lights, normally the smaller ones come with a build in PIR, we have a large yard which will need a single 150/200w led to light it sufficiently, how do you wire a PIR to an out side light..? thanks always enjoy your channel..
moxie mulgrew in the pir you have terminals L and N for incomming power and L' as outgoimg power from the pir to the lamp if you are umvertaim call an electrican on youre region
Thanks for a clearly explained video. Just a point to remember when referring to a six millimetre cable it refers to the cross sectional area of the copper and not the diameter of the copper wire. Back when I started in home renovation, I would measure the copper wire with a vernier and then wonder why 6 mm was not the diameter ? Of course not - 6 mm refers to the area - it should be written 6 mm2.
I agree with you. You did well for going extra miles
Great video. Taught me more in 15 minutes than my place of learning did In 3 hrs.
A really well presented and informative video, thank you.
Clever & superb presentation.
One of the best and easily understood tutorials I've seen. Absolutely excellent 👏
Interesting. I hadn't realised just how much running cables through insulated walls makes to the amperage rating of the cable. It's definitely, something to keep in mind when adding insulation to existing walls, ceilings etc.
very useful, easy to understand, and answered all my questions. thank you so much.
I am an electrician ,and on cookers you should allow for diversity , this is an allowance in the electrical ie regs, that means you would never have the cooker on full load ,talking the full 10kw while cooking ,( every oven and ring on full power) this means a 32A CB would be OK with 4mm cable for a short run and 6mm for a long run of cable.
No bro 6square only
Great videos, explain them clearly for all to understand 👌
Though I am not an electrician by profession but I have been in the power industry for 5 years now. It is an excellent video for learners.
The best I had ever seen too much worthy . God bless you bro
I come back and rewatch this video again to remind myself, great video thank you
thanks for the upload very informative
Thanks so much for helping me from south Africa clear and simple👍🏾
madlokovu
Well done, best technically designed and factual video on this subject.
Top marks! Excellent video - very clear. Will check out your others now. 👍
Great video this will defo help with my studying
Studing
Need more explanation; Good video, kindly upload one video on, how can we calculate Short Circuit of cable.
Good interesting video 👍👍👍
Thank you very much for your clear instruction and for following the regulations guidelines. I hope you can do much more youtubes about this subject. I have learnt lots from this.
Thank you very much for the up to the point video. thumbs up man.
Your a legend no other words....amazingly trained and educated
Nice video and very helpful information thank you so much sir
I have just watched the right video at the right time. Thank you for An excellent presentation
You did great explanation 👍🏼👍🏼
this video is brilliant / really easy to follow for anyone. thank you!
I like this simple approach to calculating the design. I can't see a problem with using cable that's over-rated at is has less resistance and can cope with future changes to circuit usage. Diversity is an optional consideration if you don't want to spend too much on cabling etc. but it takes no account of future usage, so having larger cables is fine if you want to pay for it.
What do you mean take the "diversity" into account? Is that the tollerance of the cable? O you mean 1 usage of voltage between L1 and L2 ? He choose 230 Volt and that is between L1 and Neutral, so there is no square 3
Yes,it eventually boils down to cost.People often add extra loads to circuits without considering the cable power rating.
Helpful video. I'm level 2 electrical installation student . Can't wait to become an electrican .
Hiya. I'm enjoying your videos Buddy.
Just thought I'd mention it, as you did choose to use a cooker as your example.
Don't forget to apply diversity as it is highly unlikely to ever reach its maximum demand due to the thermostats in the cooker rings.
In your example (44 A) it would be the first ten amps (10 A) then 30% of the remaining amps (approx. 11 A) PLUS 5 A if there's a socket outlet on the cooker isolator.
So, your 44 A has gone down to 26 A. The next MCB up from that is a 32 A.
I'd still use 6mm cable though.
Kevin McNicholas I've always been told to use 10mm by my boss..I suppose this would save money if working for yourself.. I've recently sat the 2391-52 exam,no one could give me a exact way too work out maximum demand/ diversity nt even in bs7671 book
cater4anytink Yeah, I know what you mean. I suppose it would be useful to if the oven was ever upgraded again. It's a trade off though, isn't it?
If customer wants to pay for cable that is far and away able to deal with the demand, fair enough.
Thing is though, why don't we do rings in 4mm instead of 2.5mm? Because of cost, that's why.
And if your wiring a lot of houses that's going to be a lot of wasted money.
If customer is willing to pay the extra i.e. maybe £45, let's say, instead of £30 then yes, do it in 10mm.
Diversity is covered in the On-site guide.
cater4anytink checkout the best sparky in the U.K. he knows the regs in his head, can tell you the reg and the page its on, his name is john Collins, his training place is in dudley West Midlands, he is a great trainer, he used to teach at sbc college, he teaches in small groups, like two! On different meters, as everyone has different meters, etc, everyone knows him, especially the regs guys, ex military,
smartchip
John Collins? Ha, ha... you mean 'Johnnie Ace'!! Oh, he's great. I love watching his vids. Very knowledgeable and puts things over in a way anyone can understand.
Johnnie Ace, (tsk,tsk), is on the case. That's a great catchphrase. 👍🏼
smartchip what's his youtube page. Cheers.
Thanks for explaining this very clearly in this video. God Bless
Thank you brother can you please help me with this knowledge I'm said from Zanziber in Tanzania
thanks to share the power cable information for tips . as an wire and cable making supplier in China that we learn a lot from your channel
Another brilliant video.. Great stuff
Great Video. Thanks for taking time out
probably the best instructional video out there. thank.
Informative video about cable sizes
Excellent explanation. Thank you for this educational video.👍👌
Howdy.
Nice presentation of rating the thermal overload case. There is, however, another equally important aspect. The short cicuit case. There must be enough "short force" feeding the breaker to enable fast breaking (=magnetic triggering) of the breaker.
In my location the power companies will provide information of how much short current is available at the service cable junction. From this point forwards one must calculate the short current at the most distant appliance or socket and choose a breaker that will fast trigger.
If the short current is too low to deliver fast triggering the short current will flow until the thermal breaking happens. The socket wiring will run way too hot and there is a real fire hazard present.
Regards.
Sir thank you very much for the very clear explanation tutorials on how to calculate electrical wiring.
Very informative, really good explanation. Thank you.
Very helpful video. Thanks for your time to put this together
excellent video and very well explained I ve learnt more from home electrical wiring thanks to your video
very thorough and scientific.. learnt a lot.. got me thinking a lot more :)
Thanks for your effort and a neat explanation for the beginners.
A very simplistic look at the cooker circuit, you need to take diversity into account as the load is thermostatically controlled and therefore wouldnt pull the full load all the time.
You may not pull full load all the time.Pulling it for a split second will trip the breaker.
Good video Though... Thanks for the tips and keep the good job
This is quite a broad topic. You managed to explain the most important parts, excluding the formulae.
For heavier loads we (central Europe) usually use 3 phase circuits.
he is explaining for domestic/houses
Most of the domestic-houses here DO use 3 phases + neutral. AC Voltage LN 230V, LL 400V, main fuses are 3 x 25A or 3 x 20A and current limiters inbuilt in the electrical power meter. Electric stove usually uses 3 phase, so does the heat pump, and other various bigger loads.
at 1:15 talk about cable size 6mm, 2.5mm and 1.5mm. Iit should be read as 6mm square, 2.5mm square and 1.5mm square instead. Many thanks for this video!
No mention of diversity for the cooker. Nevertheless very effective and easy to follow video. Well done buddy.
What is the diversity of the cooker
@@Vision267 it won’t run at full load
Very clear and informative video! Thank you!!
Excelent info and concise! Thank you!
This guy is amazing how hi explain to the people
Excellent video, Thank you.
Thanks for sharing it help a lot God Bless
Great video. Thank you for taking the time to make it.
Very important to use the right size of cable for the proper job :)
I need to be calculation test books .any advice .Thanks brother 🌹
Very useful.. Thank you so much, from Mizoram, Aizawl
great information and thank you very much for that.
One thing to remember regarding cookers...
If it is a three phase connection than that 44 is divided by 3, which means you can connect each of the phases separately and the cable size does not have to be bigger than 2.5mm and size of three breakers collectively has to be 20 Amps each (44x1.25=55÷3=18.33)
After waiting two weeks for a new cooker from a place that has the same name as a god, I paid for it to be put in. A bit more than £100. They said they could not do it. That I can only have a cooker thats 20 amp. I did not watch them try. My lights went off and on many times. So I went to see what the hell was going on. My fuse box says 32A . I have to wait 30 days to get my money back.
Brilliant video.well explained!!
Brilliant video, very informative. Thanks!
You have explain the calculation to obtain circuit breaker amp size and from there, select the cable size based on the table. But, I am curious about the calculation to obtain wire size. Why using 1.5 cable for ac for for example can cause it overheat. What is the maximum by calculation for current to pass through wire certain size.
prosto i konkretnie....tak trzymaj
Very nice video sir thanks from Pakistan
Thank you for a very good presentation. I am quite stunned about the wire size. Here in Denmark for a cooker it would be 3 phase and 400 V. The calculation would be like this: 10000 W / 400 V x 1,73 (square 3) = 14,4 Amps This will eventually lead to a 2,5 mm2 if it is not placed to hot. Quite a difference! It would be fused with a 3 phase 16 amp.
Forgot to mention that the wire would be a 5 x 2,5 mm2 (3 phases, 1 neutral and 1 ground)
👏👏
@@mortenlund1418 But that cooker should allow a 3 phase connection? In the video he defined a 10kW cooker that works on L1 and neutral, other people mention "diversity factor" What is that?
Do you have a link to that book in pdf form or similair pages with the required tables?
@@satish8299 this why the consumer has to check first the fuses wiring he has before buying an appliance
Thank you for yoir explanation, I only have one note: When you get the current you divided power over voltage without the power factor.. it should be P/(V*pf) so the current will be 48 A , then you should select a cable size according to that.
Thanks for the video. Can you please change the music? Something more pleasant to the ears?
Beautiful explanation boss
It was very useful, thank you :)
Simple presentation but accurate
Very nice explanation...
Sir, can you make a video on calculation of electric load for a colony and how to select transformer for that colony?
You forgot to take into consideration diversity, so take the first 10A and 30% of the remainder = 10 + 11.33 = 22.4 A approx , so theoretically 2.5mm would suffice if on a type B circuit breaker, 4mm to be safe. ( 6mm cable comes from the old days on semi enclosed fuses - where the correction factor pushed up the requirement for a larger cable)
The what? The diversity ? you mean tollerance ? I dont understand that 11.33 A
You have to assume that not all the burners and oven etc in the cooker will be on at the same time and draw full current. So we diversity meaning an average current that would be use so 10000/230 = 47amps,take 10amps out will leave 37.then you have to take 30% of 37 which is around 10 or 11 and add back the 10amps that you took earlier and will give you around 21amps. In this way you can use 32amps mcb and a lower siZe cable.
@@septin2008 I think Diversity is ONLY used to calculate the overall current demand of current in the house to see if the demand goes over 60 or 100 Amps etc. If you you diversity for calculating MCB and cable size, you would end up tripping MCB whenever you use the full load (xmas cooking etc) or if you had a bigger MCB but a small cable, then cable will burnt down when full load is used......
@@septin2008 I was told to get a 4mm.
your explain very excellent thanks lot
That book is useful
I'm gonna have that book but I would like you to explain more about that book
Thank you, Sir👨👨👨
good video
Congratulations sir.
Could you please make a video about series or parallel circuit connection of led downlight? It will be very useful for everyone
i now 1mm cu wire can hold max 8 amp without voltage drop 0.05% in lenth 100 meter and don't get hot so (1mm 8amp) , (1.5mm 12amp) , ( 2.5mm 20amp) , (4mm 32amp) , (6mm 48amp) , (10mm 80amp) , (16mm 128amp)
and thanks for your great video.
hold on , you should also take in to account the method of installation , the various conditions it will pass through (example , you may go through insulation and then into free air which operate at different temperatures
very good mate well done, this will really help people
Thanks for the clear explanation
You are The Man ...many thanks.
Lovely easy to follow vid. Thanks!!
cool music at the end, very useful info, thanks
Good Morning!
Nice work!
Three things here,
1. You didn't consider power factor (cos theta)
2. What is the phase (single or 3-phase)?
3. Please,what is the name of the handbook and how & where can I get an electronic copy?
its called On-Site GUIDE ,make sure buy the 18th Edition and you can find the all info and installation method about wiring.www.amazon.co.uk/Site-Guide-7671-Electrical-Regulations/dp/1785614428/ref=sr_1_1?ie=UTF8&qid=1543285293&sr=8-1&keywords=18th+edition+on+site+guide
1 amp equals 1 coulomb of electrons. The NUMBER of electrons in the
cable is limited by the diameter of the cable. Very informative video.
Are the lamps in the "cooker" the same voltage as the heating coil?
that book would be a good investment.
Could I ask you to do a video on led out side lights, normally the smaller ones come with a build in PIR, we have a large yard which will need a single 150/200w led to light it sufficiently, how do you wire a PIR to an out side light..? thanks always enjoy your channel..
moxie mulgrew very good explanation.
moxie mulgrew in the pir you have terminals L and N for incomming power and L' as outgoimg power from the pir to the lamp if you are umvertaim call an electrican on youre region
great video, that was big help to me .... BIG LIKE
Great video, easy to understand.
Very nice explanation, you make a great teacher; sweet memories of my work with some Polish builders because of the accent. :)
Thank u,, very clear explanation
Excellent video, thanks for sharing. I have a question if you don’t mind please , cooker 10Kw is it per hour ?
Very nice and easy to understand
very how you this video help me alot .thank you very much
Great video.... very helpful thanks
Interesting new knowledge
Good Content shared by you for us guys
> greater than , < less than, i got confused with your illustration, thanks for the informative video tho
or to help visually as well greater > than less < than