DNO fuse is to protect the installation as a whole metering etc, the additional fuse is required to protect the cabling to the CU. Not required if CU is closer.
Wouldn’t a heavy duty MCB be a better component? Fits in a smaller box, doubles up the switch and protection functions, etc.
Why was it not an 80amp fuse upstream of the 100amp main cutout? Descrimination/ Selectivity and what not
+1 .. now it's the strongest fuse who will not pop :p 50/50 chance the DNO one will trip :p
Great job,quick question, what’s the point of using a 100A isolator when the mains got a 100A alright supporting it?
If the tails are longer than 3 metres away from the consumer unit you have to put in a fused mains switch due to regs
Nice. FYI, its the meter operator (eon, british gas etc) who will install the meter. DNO own up to the cutout before the meter, so will not install that
great vid. Ive got to do one this week. what's the general thoughts on running the swa up the cavity?? If i cant get it up the cavity then I'm going to have to chase it into the block behind the dot and dab :/
Assuming the DNO puts a 100a in... your fuse needs to be max 80a. Selectivity and all that 👍
DNO will only fit 80a fuse in cutout. Your 100a fuse pointless. Really needs to be 63a to allow for discrimination between household circuit and DNO supply.
I'm DNO and can confirm we have recently had instruction to fit an 80 amp in the 100 amp cutout. The reason being it will allow 120 amp + for a few hours. The time/current curve for the BS88 will confirm this.
As for discrimination, you don't need to bother. It's 50/50 which one will fail first and if it's the DNO one that gives up first, they will respond within 2 hours anyway. In some instances ( flats with submains ) we use a red fuse link in the flat as there's already fuse protection in the Distribution board ( eg Bemco/Rapell/Schnieder boards ).
@@robtmcL12 "50/50 which one will fail first" - which sort of begs the question why these second fuses are fitted in the first place? Seems like its just some box ticking exercise.
I've done a couple of these, it's easier to curl the wires at both lod and supply side. I always leave length on cables just in case and it looks just as tidy. Not sure why earth nut or banjo wasn installed from source side as less likely to get tampered or disconnected 🤔
Tampering with Earth or Neutral won't in any way get you free electricity, it will just make the life more dangerous. So putting them on "consumer side" is actually preferred, since then if the consumer or any electrician needs to make a measurement on for example earth or neutral, you usually need to separate these (NOTE: Very dangerous, should be done with isolated supply) and then you can measure, for example, track down cheater earths (cheater earths are when you make a fake earth out of the neutral on a socket - super dangerous!) - this by connecting a beeper transmitter on the now disconnected earth, and then making sure every socket beeps. If a socket doesn't beep, its a sign that the earth in that socket is fake.
Disconnected neutrals and earths also have other usages, measuring resistance to find out cable lengths and impedance, tracing broken earths and neutrals and lots of other uses, and it would be a pity to have to call DNO or meter company just to do some troubleshooting on earth or neutral.
So always leave earth and neutral easily accessible on consumer side.
So is it purely because of the distance then?
I think a saw another video about the same thing earlier today
The supply companies use to insist that no consumer apparatus be installed in meter cabinets, has that changed ?
This is technically not true in this case when a consumer unit is more than 3 m away from the main head there has to be an isolator of some kind
@@kobirelf97 yes and it is fitted the by the meter company (same time as meter), source= my job
Nice clean job
Brilliant ❤❤
Curious if its recommended putting some kind of terminal on the bare conductor? or if this does not matter, cheers!
Why 25mm SWA and not 16mm?
@@temp06j723-pmeighttq Because my understanding is that the cable size and fuse should match the setup. The DNO fuse is 100 amps. The tails are 25mm which support amps of over that size of use or thereabouts. If you then are going to build a distribution network then the DNO then expects you to go lower in cable size and fuse to protect their fuse. A 25mm cable matches the tails which isn’t the correct way to build a distribution network hence the question. I think the distribution network needs to be lower cable and fuse so that if there was an issue on it then it would protect the DNOs fuse and setup but I’m not qualified and learning so if you know the answer I’d be glad to hear it.
DNO's cabling protection is another complex story.
CutOut is to protect Meter Tails etc.
When given a 100A service Cut Out, you wouldn't be fitting a 16mm² Tails unless you Downsize the Switch-fused Isolator + fuse to a 80A then it will be fine.
But then it will be a waste, considering the ability the DNO to Service up to 100A yet we downgrade our PERMANENT Cabling(meter tails) to a lower size that Forever is Binded/capped to 80A in the future (with using of 16mm²).
Hope it makes sense.
What grips did you use please
22/58 100a fuse is an European style industrial fuse NOT a domestic 22/57 house service type. Any short circuit fault would blow the DNO fuse and not the one in the switch fuse,I've seen this happen before,these fuses have a much higher watts loss and pre arcing values are higher
Do you not usually use the grey for the earth and black for neutral or doesn’t it matter as long as it’s sleeved?
Deneutralization of black means it will always be CPC and grey will be the neutral mate
Denuetralize the black always grey is neutral and should be sleeved blue.
I do the same, but really there are no regs, as long as they are identified correctly.
@@_eusty there are regs for it, if you look in the regs book where it lists the colours, now black should never be used as as a neutral with new colours
Any reason why you didn’t use a stuffer instead of a swa gland as it’s earth distro end ?
I've used these once, personally I prefer the metal swa glands feels better even if
it's just my excuse to get grips out and show off 😂
Is it possible for the switch to go off but not blow fuse?
Why are Meters now fitted on the outside of the house?
So the powers that be can gain access to it without you needing to be home.
They cant enter your home by law unless you let them in.
If you build a metal cage around your outdoor meter then they cant gain access and if they break it to get to the meter its classed as criminal damage.
Whats the limit on how long the cable run can be in this situation?
No limit really. But you have to size cable correctly for voltage drop. (And i do not mean limitless as in 1 million miles... )
Mate, I`m curious how did you manage to put back the front of the Fused Switch Panel... I guess that you know what I mean.
Those switch fuses are pants, just no room in there. I always buy the Wylex ones ,plenty of room in them.
Wish I’d seen this comment before, fitted a niglon yesterday, fuck all space in there.
Great work mate… the guy from the DNO will appreciate the work too. Not understanding the ball ache you had leaving plenty of room for the meter 👍
The meter provider won’t touch it. They don’t connect to a de-energised supply and on the basis there’s no room for an isolator, they’d walk away.
The meter box isn’t your’s so how do you get away with using it for your sw fuse. I’ve always had to put it either inside property of 2nd box.
@@RDavisElectrical Yes i am serious. Maybe you require more experience. Different area’s i suppose have different rules. In Cambridgeshire we had to use a separate meter box for sw fuse. We were not allowed to fit anything in with the head & meter.
I installed one for a meter move, wrestled with the 25mm 3core only for the DNO to put in cable that was no bigger than my thumb! What’s that all about?!
Just curious as to what is the need for another fuse next to the main fuse?
Also i hope the extra one is faster then the one from the DNO 🙂
Seems a bit useless 2 100A melt fuses after eachother .. if the new one trips first your lucky .. you can replace it .
If the DNO ones trips you have to call DNO or break the seal . ( kinda funny in uk they do'nt have automatic fuses from the DNO .. proably because melt fuses are cheaper )
It’s because the cable is over the recommended distance. And runs in the fabric of the building.
how come the cables dont come with the right colour? Brown, Blue, Earth
Because the cable used was 3 phase + armoured (earth). Not sure why you wouldn't use 2 core, plus armoured.
@@StuartJ Having Earth as a wire in the cable from meter to the unit is more reliable than relying on the armour
hi, anybody could explain when we could place 63amp, or 80amp or 100amp? after installed smart meter it increased the bill cost, burn off extractor, washing machine, hair drier, thank you have a nice day
Pay slightly more and you can have colour coded SWA ….BROWN..BLUE …GREEN/YELLOW ..worth the extra .
It’s really no time at all to put the heat shrink on, plus the heat gun kept my hands warm 😂
+1 i really don't get this .. seems every UK elektrician buys the SWA for industrial 3 phase use with black/brown/grey . And changes the colors . Here in Belgium this is not really allowed as it is confusing .
Using a black conductor for PE etc .. just buy the correct cable for domestic .. and it seemes UK is 99% single fase in houses .. should be no problem to find correct cable .( in Belgium we call this 3G16 / 3G25 . The G tells there is a ground wire( CPC yellow green in ) and 2 wires for current blue and brown(or black ) .
@@_eusty yep for 3x400V industrial use the colors are correct .. and NO neutral wire . And CPC is run seperate .. So domestic elektricians just buy the wrong cable and relabel it .. Would not pass inspection here official . the color has to be the same for whole cable ( so recoloring black to green/yellow is not ok here ) . But i think in UK after installation no external company needs to inspect the electricians work and aprove .. i have seen many do it on youube .. so i guess it's allowed in UK ..
Hence the sleeving….
If the sleeving is blue or green or brown, then that states what the conductor is. 👍🏻
You won't be getting a smart meter in there, the meter fitter can't check for tightness on your tail going from iso into the meter
Nice one Ryan that is always a bitch of a job. Even if you do armours every day.its still shit. You made it look easy keep up the good work. The only thing I do different is I take the grommet out of the gland and put it back in, so the 2 25 mm holes are at the back.
Should you be fitting a 100a switch fuse?
that would probably trip faster then DNO (melt) fuse. I would go for this approach i think.
Don’t suppose you had to move the new enclosure about 3mm to the left to get the cover on did you 👀🤣
I would have put the tails gland above the main switch they would have gone straight in ..
And fit an earthing nut on the swa gland .
Top stuff
very helpful video....
👍👍👍👍👍
Bin the banjo, Use Earth Nuts - It is 2022!! 🙂
Also you have left that WRONG, the Isolator should kill the fuse, not a slick mod!
Probably a job for CW, NOT a BW Gland as well....
😁✋✋
Fuse switch
Хм, запасика у нуля нету
Leaving extra length of the armoured would make the job easier i believe .. Well done sparky 👍