Wylex Fusebox - Replacing fuses with plug in MCBs is a waste of money
Wylex fuseboxes with rewireable or cartridge fuses are very common in older properties. Plug in MCBs can be obtained for these, and are simple to install.
However doing so is a waste of money, since the MCB does not offer any additional protection compared with a fuse.
Both devices disconnect the power in the event of an overload or short circuit.
The only advantage of the MCB is that is is quicker to reset - but fuses should fail almost never, and if fuses require replacement often, there is some other problem which no replacement device will fix.
New consumer units will contain one or more RCDs, which will disconnect the power in the event of an earth fault, such as someone touching a live wire.
It is impossible to fit these into old fuseboxes like this.
It would be possible to add an RCD separately before such a fusebox, and there are some installations where this has been done. However adding an RCD in this way does not comply with BS7671, as in the event of a fault on any of the circuits, the entire installation will be disconnected and will remain that way until the fault is located and repaired.
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Not only are the circuit breakers more convenient in terms of reinstating power, it's makes identifying which circuit has tripped far easier. If your fuses are blowing all the time, it's probably best to get an electrical safety check done on your house.
I can think of three reasons why you might want to fit the MCBs, as I did to my Wylex consumer unit many years ago. It's cheaper than replacing the consumer unit, , you don't need an electrician, and it makes it easy to turn off individual circuits before replacing light bulbs, for example.
For such a cheap upgrade it’s definitely worth it. When a bulb blows and burns out the fuse wire, my elderly parents can restore power by themselves. That alone is a good enough reason
When the fuse-wire blows, it's not usually a fault with the installation, but an old style incandescent lamp blowing (or a tungsten halogen equivalent). My father who is 85 now has found the replacement MCB very useful, especially as he has only one good arm after a stroke, and replacing the fusewire is fiddly for him. The other point to mention here is the price of LED equivalents which are not yet up to the brightness of old 100W lamps with the same colour temperature, ie 2700K. have a noticeable reduction in light output with time. I have tested the reduction in light output on LED lamps, especially those with SMD's, and a drop of as much as 25% happens within just a year. If 6000K lamps are used, the blue light reduces the production of melatonin, causing people difficulties getting off to sleep, or insomnia. I say bring back the old incandescent lamos!
It’s sad that the lamos is now extinct. I for one have never heard of it but if it can be brought back to life so well and good!
I have only had to re - thread a fuse wire once. doing it the dark, holding a torch in my mouth convinced me that pressing a reset button once in 14 years is worth it, even though apart from convenience, there is no value - add in replacing them
If the fuse goes it's a pain in the ass to fiddle around with the wire especially if it's the lighting that's blow....and it's night. You also hear about people using bits of metal instead of wire. For these 2 reasons alone I would change to MCB's .
HILUX CHAINSAW Exactly. Plus, you avoid the smell of burning Bakelite, if you have an old fuse box like we have.
I recently upgraded some BS3036 rewireable fuses, as the external Earth fault loop impedance (Ze) was extremely low. This in turn gave a very high prospective fault current, somewhere in the region of 2.5kA. The old rewireable fuses were only rated (S1A) or 1kA. The newer plug in mcb’s (to BSEN60898) are rated to 3kA. Hence the reason for the upgrade. I suggested a consumer unit upgrade as a first option however, the cost was an issue so this upgrade was the cheaper option. I would agree with some of the comments that an MCB is more user friendly, for instance, in the case of an elderly customer who’s is trying to rewire a blown fuse holder in the dark. 🔦
The plug in MCBs may not offer much additional protection but they are 10,000x more user friendly. Worth every penny.
If you are unable to screw in a piece of fuse wire you probably shouldn’t be allowed to live on your own 😂
@@timothyasbridge8562 Does hating on the disabled make you feel big?
a few days ago, my sister had a lightbulb fail, and the bulb took out the fuse for the circuit when it failed my sister had to call out an electrician, and the electrician replaced the fuse with a circuit breaker
@@timothyasbridge8562 , 6 am winters morning, up for work, losing all your lights isn't good, MCB so much easier than fuse wire.
@@timothyasbridge8562 disgusting comment
Superb. Just what I wanted to know. Short sharp & to the point video inclusive of relevant safety points. Well done you & thanks for sharing. This type of information actually saves lives. Much appreciated !!!!
We have had a fuse blow for the first time in 37 years. It is a real pain having to thread the wire through. It comes from being wound round a piece of cardboard, getting it straight enough to thread through is not easy. Nor is getting the fuse unit out in the first place. There is something wrong in the wiring, so we have now rewired it about 4 times. I would certainly recommend a circuit breaker replacement once a fuse blows.
Very helpful and easy for a non-technical layman to understand. Clear information and advice. 👍🔌⚡
These MCBs do have a use on lighting circuits, were a cheap GLS lamp with no internal fuse can take out the CU fuse when it fails. Also the non-combustible CU reg change isn't retrospective.
Been there at 6am on a winters morning before work, all lights out and you got to rewire a cartridge in the dark. MCB so much easier.
@@jasonsmith4888 Catching up?
@@Graham_Langley yep knew it was an old post but knowledge is knowledge.
Probably the greatest advantage with an MCB is that when a fuse blows then someone who has no idea what they're doing may replace it with too large a fuse or something else entirely (in some cases a nail or strip of copper!), and then the circuit is no longer protected, but an MCB is a bit more fool-proof.
exactly I know someone that was going to put a 30A fuse wire in a 5A fuse carrier - SCARY
@@adventuresofanathan what wud happen? can u elaborate
@@ggoog1845 the fuse wire wouldn't break when there is a fault present, causing fire or shock risks.
That don’t bear thinking about.
I moved into a house in 1978 that had exactly this fusebox. About the first thing I did was replaced the fuses with plug in mcb's just like this. Worked for many years until the house was rewired as part of renovation. (I'm embarrassed to say how many years!) In this case I disagree with John.
indeed you may as well upgrade the whole CU for what it's worth, but for a few quid they are more sensitive, and also prevent any abuse with incorrect fuse wire being fitted etc...
Thank you so much for this video, i have have fuse box, like this in my house, mine is cream, i have had no problems at all. Was thinking of getting those MCBs however if it is not broke, do not fix it. I do not overload, and no fuse has ever gone. All these new regs, are all there to take If the old ones are bad, how come they lasted so long. Look at Grenfell tower, if that had just been left alone, without the cladding, just a concrete structure, it would not have happened, and the Boeing Air Max once again, the new one, they could have stuck with the old model, and they had serious problems, The Russians, never bought the latest, models of airmax, they stuck with the one before, cost a fortune. These work, and they are safe, and i have had no problems at all, So many times, i have seen the latest cause problems, or cause different problems. I was at a church recently, and the preacher was telling everyone that his Electrics kept tripping, the Electrician spent a whole day looking where the fault was, he could not find it, and may need a rewiring. It was difficult without light. The same thing happened at our Table Tennis Club, it kept tripping, they think it was the refrigerator door. It had to be rewired, and new sockets put in. It had been fine for many years, no problems. You have to be careful. I read on the internet, Wiring PVC the copper can last upto 100 years, and the grey sheath covering, can last, up to 50 to 70 years, it all depends on usage rather than a clock, it it has been changed, constantly tampered with, overloaded, it will not last that long. So this box, andi like they way has explained it in a fair way is still useful under the right conditions. There will be some Electricians, who will mention it is dangerous, fire hazard, need to up dated, illegal, is too old. The suckers among us will soak it up, and get frightened, and pay out a lot of money, when it did not need to be done. If it is that bad, how come i have no problems with it in 30 years, no nothing, that is the evidence, i like this video, and it explains that, Well done, your a star, helping the public, forget the MCBS they might not be better in this case, Thank you so much, as worried about this subject.
The MCB also has the advantage of being able to be shut off without exposing line voltage.
yes...which is quite important for me as my shower pole-switch has broken in the on position and the only way to turn off the power to the shower unit is via MCB
Thanks for sharing your information. You present it in a easy to understand way. Following from Sydney Australia
BRILLIANT video. Thank you John. Clear information which has just saved me ???£'s. I was mind set on replacing my old fuses with trip switches thinking the trip switch would save anyone (by that I really mean me) being electrocuted if they did touch a live wire.
TheHairyHound I would check to see if you have an RCD in line! Has a small button labeled test! push it and it should trip, also to increase your safety see if you have green/yellow wire attached to your gas/water
Fuses only protect devices etc fron causing a fire. If you get electrocuted and killed, the fuse probably wont even blow. You needs to have a RCD, big thing with a test button and switch.
Fuses only protect devices etc fron causing a fire. If you get electrocuted and killed, the fuse probably wont even blow. You needs to have a RCD, big thing with a test button and switch.
drkastenbrot incorrect.
LOL at anyone who thinks that installing MCBs will make it safe to go around touching live wires!
Excellent video John. I shall start looking for your others. Mike
I have one of the old MEM fuseboxes rather than the more compact Wylex. For convenience i bought spare s/h ceramic fuse cartridges (off ebay, and yes, they were expensive) in order to simplify the swap. The MEM cartridges take a little longer to wire and it is easy to be hamfisted and stress or snap the wire when tightening the screws.....better to have one of each spare kicking about- 5A, 15A ,30A.
It's worth every penny. I just had to rewire that freaking fuse in dark. Good thing I had last bit of spare wire
My Wylex is a wooden one like that and that's the way it's staying. I retrofitted the latest MCBs (its a 4 way) and an outboard whole house RCD. There's no way I could get anything else in the meter cupboard as it's an outdoor one with meter, bell transformer and garage isolator. Full! MCBs are also classed as 'close circuit protection' which is no doubt renamed something less informative these days, and allow greater tolerances on circuit diversity, cable capacity and impedances than rewireables. There used to be tables of capacities in the IEE regulations for rewireable vs HRC/MCB protection, though I think the trend for over-complicating and obfuscating the rules has meant we now have confusing derating factors under the present IET tenure as electrical God.
thank you a very useful post and very well explained
Good video and sure, a modern consumer unit with a built in RCD is better. I would still rather see a type B mcb used in an old consumer unit on a lighting circuit than a traditional fuse though if only because it prevents people from replacing the damaged fuse with something inappropriate. You didn't even mention the different tripping characteristics MCBs have compared to fuse wire or that mcbs are more sensitive to fault currents than fuses. These are important considerations for people who cannot afford to replace a whole consumer unit.
Thanks John. Very helpful to know.
Good video. Interesting to see that the rewireable fuses in the UK don't have a so called tortuous path. The colourcoding is good. Pity that not all MCB's stick to the standard colour coding. Rewireable fuses are about 1kA rated.
In Germany go in 63A (3×230V) normally, starts with a MCD with 63A/3x230V as main fuse and then every line have MCD 16A B character. For bath room or outside power sockets we should install RCD 30mA, in older installation (my appartment) come one RCD after the main fuse. For working places with heavy machines use MCD 16A C character. Newer installations make extra lines with differ RCD's, start with high 100mA, then 50mA, then the lowest 30mA. Example: Main fuse - RCD (for all) - MCD (all) - RCD (for kitchen) - MCD (kitchen) - RCD (for power sockets) - MCD (power sockets) / RCD (for living room) - MCD (living room) - and so on ... Possible an extra line for lamps only - so that lamps not go off in night if washing machine chrashed RCD. But only RCD as once replacement for every MCD I never hear here in Germany. This we never do. In Thailand in opposite I be happy if we have fuses into the power lines ...
I have a similar type Wylex fusebox, biut 8 positions (I think), about 25 years ago I replaced the fuses with the MCB's and fitted an external RCD, has been good for me, was cheap too. Ideally, a new consumer unit and a complete house rewire would be nice.
Very informative John. We have a consumer unit at home which only has MCBs in it, but not really enough space for 2 RCDs to cover 2 sets of circuits with the MCBs that are already there. Is it worth replacing the lighting and power circuits MCBs with RCBOs as they would only take up the same space in the consumer unit?
Brilliant Video, Thanks for the tips.
Whether its an MCB plugged into an existing fuse socket or a complete new unit with circuit breakers and RCDs, a circuit breaker is far better than an old-style wire fuse because you can see at a glance which one has tripped. Number of times I've had to pull fuses in sequence and look to see which is the blown one just because someone has decided to plug in one too many devices on a single circuit. Our current house has two fuses for lighting and four unlabelled fuses and a plug-in MCB for which the labels are illegible (it also has a retrofitted RCD with two circuit breakers). If half the lights go out in the house, it's a 50% chance you pull the right fuse first out first, if an electrical outlet goes out, unless its one that's controlled by the MCB, it's anyone's guess which of the four fuses is the right one. Interesting to note that the fuses in the video would not be acceptable here in New Zealand as they would not comply with our code - our fuses have to have a "tortuous path" whereby the wire starts on one side of the ceramic block, passes through an angled hole in the block and then is fixed on the other side so it forms a Z-shape. A straight wire like the ones pictured would not be legal here.
From experience of 40 years have had 100s off these Rewireable Fuses to change, and always recommend upgrade to Plugin MCB as a cheaper 1st option, as No mistakes with Fuse Wire, even when we were using the Push Button Type, reduce the risk. Yes- Upgrade the Unit and these New Plugin MCB are Very Good and NOT Like the Rewireable which are a Death Risk and had Many with Wrong Size F.W and even Copper Wire which is like 1000 A .
I don't think these circuit breakers are a waste of time at all. I've just been in a situation where my lighting fuse went due to a bulb failing. I'd purchased fuse wire but couldn't remember where I'd put it. Unfortunately the gas heating control system was also on the 3A circuit so I had no heating and it was the coldest day of the year! I also think forcing the average consumer to physically wire a fuse is an anachronism and inherently dangerous. The problem with engineers (I do engineering from a numerical perspective) is they assume everybody thinks like they do; your perspective is a classic example of this: "it works perfectly well, so it doesn't need fixing".
Agreed. I do electrical installations and I try to see things from the user's perspective. It's my job to foresee scenarios where a paper clip or tin foil might be used by a desperate customer on a ladder in the dark after trying to find the correct fuse wire for the lighting circuit. Changing the whole fuse board might cause him financial hardship. £10 for one resettable MCB? I'd splash out and get two!
You havn't mentioned 'Fusing Factor'. A BS3036 rewireable fuse has a fusing factor of '2' which means that it will carry twice the rated current for up to 4hours before disconnecting. A circuit breaker has a fusing factor of 1.45 and will therefore disconnect at a lower overload current. Because of this the 17th Edition Regs applies a fusing factor where BS3036 fuses are used which means essentially that a larger cable size has to be used when BS3036 fuses are used. Other benefits of using circuit breakers is that they have fixed values of tripping current and cannot be meddled with as with the fuse ie.incorrect fuse wire being used. There are other benefits to using circuit breakers and in short I would recommend their use.
Geoff Bryant Missing the point. JW is saying renew the whole consumer unit.
Cost of the hardware may be similar but just upgrading the fuses doesn't require using an electrician.
Ummmm the trip or blow speed at which a MCB or BS3036 is dependant on rating and fault size ...for example a 5 amp 3036 will trip in 0.1 second at 45 amp fault and 5 seconds with 13 Amp fault as per Fig2a of bs 7671 (in older editions only).
I will fit them for infirm customers where fuse wire is too fidely for them and have swapped over 100's in shops and national trust propeties, where cost is a big problem! In some cases ease of restoring power is more inportant. I believe the Zs values are different for the 3036 fuse wire compared to mcb types. But at the end of the day the cost of a new board in the uk is not just a straight swap, we are having to carry out small periodic inspections before replacing boards because theres nothing like finding a shared neutral once you've installed a dual RCD board! =)
Handy explanation, thanks 😀
waste of money till someone puts 30a fuse wire in their 5amp lighting circuit! Circuit breakers are much safer and prevent this, don't agree with your video on this. Plus that consumer unit wouldn't fail an EICR as it was installed to a previous standard, you just couldn't fit it in a house these days, not that anyone would mind!
Lol. "It's a waste of time spending £40 on circuit breakers to replace the old fuse wire units". Much easier to spend ten times that on an electrician to install a new consumer unit.
Straw man argument.
£40 spent will be wasted as the MCBs will offer much the same protection as the good fuses you throw out. The easier reset is a plus, but if you're having to reset often, check your wiring over. If you spend ten times that on a sparky, you will get a much safer setup, so the two scenarios are not equivalent.
S. Giles says the man with a response like yours. £40 layout for easy and quick resetting of a circuit or £400 for a fuse board change plus potentially another £2000 to rewire your entire property because it doesn’t meet current regs(which it would have to once the fuse board is changed).
Spending £40 for not improving at all the security of your installation or spending ten times that to have a more safer installation with a RCD that could save your life.
@@alerighi The OAP stuck with no light or power would much prefer a switch which can be reset. Leave off the one the takes the power off. You would be glad of that when you get older as you will!!
a point well made, thanks
i understand what you mean but its not really that much of a waste of time or money. it offers convenience to a client and looks and feels much more easier and safer to operate for say someone who does not know a thing about electrics and dosnt want to go fiddling changing their fuses. But i understand what you mean
i came across one of these the other day but without the wooden thing but a RCD was fitted in later it had some old resettable MCBS plug in type the RCD was to the side protecting the entire property to what i guessed, luckily i had a portable Residual current device with me ( the ones you plug in and plug your device in) as it was a old house that i assumed cos of the age had just MCBs which has no protection from a electrical shock then RCDS. If i was in a house with just a MCB fuse box for safteys sake i would upgrade to one with RCDS in it. my fuse box at one of my parents houses has got a big RCD below the fuse board as its a older fuse board where half the circutes are protected and some are not but the RCD below if that trips it trips the entire house hold electrical supply and we know it works as we once had a boiler leak and woke up to a house of darkness and found out that the main RCD tripped and it tripped when we was converting one of our lounges to a ground floor flat that a builder burst a water pipe and it went on live wires and tripped the RCD, if that was a MCB we would have a potential fire in our hands luckily im fire extingushire trained and had to use a fire extingushire for real when someone set the oven gloves on fire which was smoldering like mad as i did not know it had flame retardent materal and plus i didnt want to take any chances i quickly got a 20+ year old water fire extingushire which still worked, manufactured in either 98 or 97. I knew that it would come under the A class catagory so i got water, we had a powder one but was upstairs but had a astmatic in with us so i did not use it as i know it can cause breathing differculties.
Very useful. Thanks.
I know the unit is not connected to anything BUT you are demonstrating working on an OPE fuse box with the switch in the ON position !
My lightbulb blew today in my hallway. I removed the bulb and switched back on the tripped switch (like the second type you showed without the yellow button) but none of the lights in my house work now. Has the fuse in the box died or do you think it is something else? If it is the fuse in the box is it easy to just unplug and replace and do you know the price and where to buy? (UK). Thanks
Question for you John - I made an circuit breaker for powered projects so just in case I get the wiring wrong, I would trip my circuit breaker instead of the house power. Now, I tested my curcuit breaker in a shed that had the live and neutral reversed (for some reason) and I purposely trip my circuit breaker,. Not only did it trip my circuit breaker, but also tripped the power in the shed?? So the questions are - Why did it trip both when it was designed to only trip my circuit breaker? Would the fact that the live and neutral are reversed something got to do with it? I have a video of the circuit breaker I built if you need to have a look at it but it's just an 20amp RCB0 with a plug on one end and an extension socket on the other. :-)
Not a lot to go on there but if you turn the socket circuit off only while you rewire a socket and accidently touch neutral to earth even with no power to the sockets it will trip the rcd for all circuits on that rcd, many of us have been plunged into darkness and not sure why. I think yours is the same issue due to the reversed wiring.
Surely a major benefit is being able to isolate a single circuit via a switch without turning off the entire board, as opposed to pulling a fuse from a circuit that might still have current therefore causing arcing as the fuse is pulled?
In the US where required the GFCI 5ma trip is used in to protect people. A greater then 30ma. trip is used to protect equipment. Are people properly protected by the 30ma trip device in England. Receptacle outlets protected by the 5ma trip device are allowed in bath rooms in the US with minimal location restriction.
When you haven't got money to get the main unit replaced, the Wylex unforunately is the best option for me at the moment until we can afford the have the main box replaced (which we know needs doing).
Hello John, I just had a case of exactly what you described on your video. quick question please, do I need to get a consumer unit with two rcds or can I buy units with one rcd only? many thanks
corfiot21 you need a fully qualified electrician, it is illegal for you to change it yourself unless you are qualified(which you clearly aren’t).
ben weston Depends on which country he lives in...
I love how you only replied to comments that agreed with you lol.
My fuse goes everytime a light bulb goes pop. I'm currently sitting in pitch dark because I have no fuse wire and the soonest I can get it delivered to me in 2 weeks! My kingdom for these switches!!!
John, where on an old Wylex 3036 db does it give it's device designation, ie S1A, S2A or S4A indicating its rated short-curcuit capacity 1,2,4 kA respectively? I was told if you are unsure to take it is 1kA. Changing a rewireable fuse with a push in MCB can change the characteristics of the curcuit and in some cases help comply with the 17th?
The Wylex boards and fuses are not marked - they are either 1kA or 2kA, but no reliable source to confirm which they are. Not normally an issue, since the supplier cutout fuse will provide protection up to 16kA, this is one of the tests in BS EN 60439-3 Annex ZA (previous standards were similar, it's been in there for decades). Actual fault levels in domestic premises are usually far lower than that anyway. MCBs will certainly have different characteristics, the .725 correction factor can go for a start - however unless the original circuit was grossly wrong in the first place, it's not likely to make much difference. May be of value if it was a 30A ring with 2.5mm/1.0mm T&E. Either way, there is still the lack of RCDs, the flammable enclosure, maximum 30A per way etc.
Thanks mate
Thank you.
To be fair, what you should be advising is that the installation should get a condition report done? Even with the consumer unit replaced, if the fuses were popping on a regular basis, this issue is only going to be transfered to an MCB/RCBO! But as you correctly state, if the fuses are blowing frequently, there is clearly a serious issue somewhere within that circuit! Generally speaking this will usually be circuit overload, high resistant joints, faulty equipment...
so what if you've no 5 amp fuse wire an you stick 30 amp wire in the carrier.these plug in mcbs would stop that so that's a good point with them surely
No, you'd just stick a bit of copper wire in if you had no fuse wire laying around. Quite dangerous. I'd say this guy is on some sort of personal mission about money waste. They are definitely worth updating.
Spot on John. Whatever you do don't become a politician, because if you do, when you speak to members of the parliament they will look at each other and think, how the fuck did someone with so much common sense get the fuck in here. CHEERS From Australia.
They may be plug in but surely if they are made to type B MCB specification, they provide finer circuit protection than a rewire fuse for both overload and short circuit?
Is it not the case that MCBs are faster to respond, and respond to more conditions (heat and magnetic)? I thought that was their key selling point, but am interested to know if that's not the case.
MCBs may be faster in some cases but not all. They have magnetic and thermal parts to operate on short circuits and moderate overloads respectively - something which a fuse can do either by vaporising instantly or slowly heating up and melting.
I note that the mcb unit and old wire fuse cartridge you show in video have different pin sizes. i.e. the mcb pins look closer together. Will they still fit into the old consumer unit?
JAROMELIA Different ratings have different pin spacings. MCBs are supplied with a plastic shield which has the correct spacing, it is necessary to change the plastic shield when fitting different devices. The metal contacts in the fusebox are much wider, so will accept several different ratings / pin spacings.
good to know, my garage in 1990 was wired with a wire type fusebox (as most eveyrthing was used, but high quality metal stuff) its never blown a fuse anyway, but i dont want to bother changing them either!
main reasons are when you are doing work in the house, replacing light fittings etc, its easier to flick an individual switch than try to pull out the whole fuse. Its cheaper than replacing the whole consumer unit which most electricians rip you off as well as insisting that the whole house needs rewiring for a few grand!....Bought 6 of these from Screwfix for a tenner each, a lot cheaper than a rip off sparky thanks
I understand that the new combined MCB and RCD devices are referred to as RCBO's ? Are the RCD and RCBO devices rated at different amperages (5, 15, 30 amps etc.) like the old fuse wires ? Is the ultimately "safe" installation to have separate RCBO's on each segregated circuits like lighting and plugs ? I am referring to the upgrading of an existing installation in an old house. Do you know what new installations in new houses are like under the current regulations ?
meandmymouth RCBOs are available in various ratings, 6,10,16,20,32 etc. just the same as MCBs. Virtually all circuits now require RCDs, so the most common options are circuits with individual MCBs divided between two RCDs, or individual RCBOs for each circuit. Both are equally safe - however the RCBO option is superior, as this means that a fault will only affect one circuit. With the dual RCD arrangement, a single fault will cause multiple circuits to be disconnected, and remain that way until the fault is located and removed/repaired. While this can be mitigated to a certain extent by having upstairs / downstairs circuits on different RCDs, it is still inconvenient and ultimately a poor solution. The only benefit of the dual RCD type is it is cheaper than all RCBOs - hence consumer units sold in DIY stores are usually of that type. Previously it was permitted to have one RCD for the entire installation - this is no longer allowed, as although just as safe, means that any single fault anywhere can cause the entire installation to be disconnected. This is hugely inconvenient as it leaves the whole house without power until the fault is located and repaired.
***** Many thanks for your most helpful advice.
***** i still have the old set up where its just a main breaker and mcbs with no rcd or anything..i believe its fine since i dont have any cirucits outside or in the bathroom..its pretty safe to be honest
***** I have a consumer unit with one RCD and multiple MCBs. Can the MCBs be replaced with RCBOs, or do you need a new consumer unit? I saw another video, where you took a MCB apart, to explain how it functioned. A similar video on a RCBO would be interesting for comparison.
dalriada842 yes they can be replaced with individual rcbos however get it done by a proffesional electrician. save u a lot of hassle in the long run
RCD saves lives, MCB saves wires. RCDs are not a replacement for MCBs. You must use both or RCBO.
Day in and day out I find Rewirables with wrong size fuse wire in. 60898’s save that risk , although some late 3871’s / early 60898s appeared to have loose screw terminals ( burnout under heavy loads .. scary !! )
I had to do a double take when I saw the name “John Ward” I’m subscribed to a different John Ward who does videos on.... well, NOT fuses. Great video.
I still have that old fuse box... Am thinking of upgradingbut worried about installation cost? Thanks
+Liz Austriapersonaly i would charge 80 for fitting then your looking at 90 for box and new mains tails
What’s the name of these fuses so I can google and purchase a 30a one? Thanks
It's a shame they don't make gfci's or rcds to fit the old wylex box. As has been previously pointed out, I'd rather spend 12 to 20 quid each to have protection rather than 1000's (and it would be for my old house) on a new distribution board and wiring. As it stands I just have a bunch of rcd plugs around the house where items come into contact with people. Lamps. Kettle. Coffee machine, reefer, washing machine etc etc.
I have one of these old fuse boxes, my fuse do not blow, but my mains keeps tripping. What could be causing this and would switching to these fuses be able to help to not trip the mains?
If a device is tripping, there is a fault somewhere. Changing fuses to circuit breakers will not help at all.
Well good points, except you forgot human factor, by that I mean when the fuse blows and they don't have the correct size fuse wire or any fuse wire, people have been known to teplace them with strands of wire or wrongly rated fuses, my friends work for local fire service and tell me they have had quite a few fires where the fuse wire had been incorrectly rewired, (example I was given) a house had major electrical fauly the house had major fire damage, the owner told the fire service he put 3 strands 30 amp fuse wire in 15 amp fuse as it kept blowing, at least with the trip type fuses he would not have been able to do that, Saying that Screwfix often have the new type citcuit breaker boxes (2 rcd's and 8 standard circuit breakers for around £50:00 so logicaly would pay to replace it
Steven Reynolds Ha, funny you mention that. I was speaking to a mate at work yesterday (we're meat workers, not electricians) who purportedly 'raped' half the dashboard of his car in order to get enough 'copper wire' to slot into a fuse holder whereby the fuse kept blowing up to three times per week or more ... fixed the fuse problem, but claimed the switchboard turned 'white' before the whole house required a complete re-wire!
Steven Reynolds I'm really unclear why the British regulations ever allowed rewireable fuses. That seems like it's just asking for trouble. It's not like ceramic fuse cartridges are terribly expensive.
Jasper Janssen These are very old fuse boxes. Before the age of DIY, most home owners called an electrician. As more house fires and electrocutions were linked to abuse of fixed electrical wiring and fittings, so the regulations gradually change. But even after the change in regulations, as most are not retrospective, old fuseboxes continue in service because most people don't want to spend money on replacing them. But are attracted to retrofitting these MCB modules. Even though, replacing the whole unit is the better long term option, as the included RCD(s) provide(s) extra protection.
Mark 1024MAK I’m an electrician and I constantly tell folk to do the correct thing and change these as nearly every one I go in is burnt or got the wrong fuse wire in it . And more seriously ( wait for it ) A NAIL. Yes that’s really right a nail you hammer into wood . Now I’m glad I seen this as it would take the board of the wall and into the garden when this blew ( if at all may I add ) 🙈. Some people are just not worried about danger until the worse happens . They are staring at the fire brigade hosing down their house . Or someone gets hurt . Be sensible , be safe . 👍
My old dad had a short in the garage once (a cable was arcing) and on christmas eve he upped the fusewire in the wylex using the little carboard fusewire packs, until he got to 45A when the main supply fuse went bang. His excuse was he didnt want the freezer defrosting, the man from the electricity board was most understanding.
This vid did actualy help me. As finding fuse wire has proved near impossible
So can I replace the old one with the new one
i replaced some of my board fuses with single b type mcbs minimum available was 10A whereas a single strand a Cu wire burned @ much lower fault current, i did that cause at some point or later the fuse assembly would make arcing clicks which is dangerous.
Are the wooden backed ones still legal? You said in your video that they may not be in 2015. We have one in our rented property but the landlord literally refuses to change it to a RCD unit. Hoping something has come out to make it a requirement to have it changed.
They don't comply with regulations now, but that doesn't mean old items have to be replaced either - they complied with the regulations when they were installed. They should be replaced for the flammability issue, and the fact they will have no RCD protection for any of the circuits, plus if they have rewirable fuses they can easily be misused by installing the wrong fusewire. However wiring regulations are not the law, and there is no law which requires older electrical installations to be updated.
How do I take the white fuse with the switch
Does an RCCB protect against current overload, like a fuse, as well as residual current leakage to earth?
No, it has no overload protection. They are usually marked with a rating (such as 80A) but that is only the maximum rating of the internal contacts/switch. If you want overcurrent protection in the same device, then an RCBO is required.
Thanks, John. Much appreciated!
If I have one of these units would my house need rewired too? Or would an installation of new fuse box do?
Old wiring can often be used with a new consumer unit. The existing wiring should be inspected and tested as part of having a new one installed. PVC covered wiring is usually suitable for continued use. Any wiring with rubber insulation will need to be replaced. Even if the wiring is PVC, worth considering if the number of sockets, lights and so on is still suitable as older installations typically have far fewer outlets than new ones.
John Ward you need to tell the whole story, it’s not simply about PVC vs VIR, the positioning and type of every single outlet be it socket, switch or light fitting will need to assessed along with any external installation and internal bonding. The risk of needing a rewire is actually quite high on jobs like this.
Yes. You'll never get an electrician to come to the house, do the job needed, and go away again. There's always a "Ah.... can't do 'that', you'll need 'this' before 'the other'. Then I can do 'that'."
is that white thing just behind the fuse when you unplug it , is it white asbestos? in the center of where the two holes are where you plug in your fuse?
Some of the older ones were asbestos, newer ones were not. Some versions didn't have that part at all.
@@jwflame so let me get this right, the older consumer units with the rewireable fuses have white asbestos? and the newer ones with resettable fuses does not? i have come across the consumer unit shown in the video with a rcd below it before now. and what versons of the older fuse boards contain asbestos? , did wylex rewireable (fuse wire) fuse boards contain asbestos?
Sorry can u help me again when u seid the heating element needs fixing do u mean the RCD on the trip box or the water heater cheers sorry to bother u
The water heater.
Hi, why not put an RCD before the fusebox and keep the old fuses?
that would imply changing the CU to current specs as it a change to the circuit. and a modern CU comes with RCDs
I remember a BBC Rogue Traders episode that explained how someone got an unqualified electrician to replace the consumer unit in their house, because the MCBs kept tripping. Surely replacing the Board isn't going to help matters?
+Frankie Sparkes No, if MCBs trip it is because of a fault or overloading a circuit. Changing the board will not help at all.
Cheers, just asking because when watching it, they were acting like it should have made a difference or something, followed by the person saying that they no longer felt safe in their home, merely because the problem wasn't resolved…
my light circuit had popped a couple of times with a Big Bang I do want to put one of these in although I can only find 6amp ones is this OK and to remove the backing plate from the circuit board I take it you only need to power off and remove the screw no wiring is required???
+Brian Alexander Yes, they are a direct replacement, the 6A will replace the 5A fuse. However if you are getting a ' Big Bang' even once, there is something wrong which needs to be identified and fixed.
John electricians say that an MCB has to be installed before an RCD in the same circuit and not an RCD and then an MCB. is that true? does it really matter in what order they are connected?
The main MCD should be installed as first. But then do you use mostly one RCD for two or more MCD's. If you use MCD's before RCD's do you must buy many RCD's. Example: I have for my 5 rooms 12 MCD's after the main MCD in my small appartment, so I must buy 12 RCD's? My electric seller say RCD costs 25€, MCD costs 2,50€. If I calculate this into a normal or bigger house - the electric costs goes too high!
Ever tried standing outside in a storm with a torch trying to replace a wire fuse, much easier to flip the breaker switch.
No, as fuseboxes and consumer units in Britain are installed inside the building.
I replaced the Wylex fuse links in my consumer unit but they are different to those in the video, The old fuse link base is also removed and the MCB screwed in place. Each has a test button as well as a lever to reset. True, ideally I should replace the consumer unit but that is a job for a qualified electrician which I am not. Have you ever tried rewiring a fuse link in the middle of the night with a torch?
A way of avoiding to have to rewire the fuse in the middle of the night is to have spares ready wired. Most electricians who have replaced old with newer units will usually give you a few.
wattsupmike ? Have I ever tried rewiring a fuse holder in the dark? Yes. I have also rewired various electrical systems in the dark. Stop moaning and go and buy a decent head torch and battery operated work lamp.
hi john,,,I've got similar electric and fuse box but i have gone and broken the main on off power switch,snapped it in half ,yep that backer lite switch,,any ideas on a fix ? ......or any idea on cost of a new replacement ? thanks john
There is no fix - that type of fusebox is no longer made. The main switch was supplied as part of the whole thing and wasn't a separate item. Only option is a new consumer unit.
thanks john for quick reply,,,john ,,,talking about cost,,,any idea for box and fitting ?
Depends on various factors, but in the UK typically £400 - £800 for a normal sized house.
cheers john, not good news at all.
If cost is a problem, another option would be to have a separate main switch in a small enclosure fitted before the fusebox, such as this: www.tlc-direct.co.uk/Products/WYREC2S.html
These old wylex boards are potentially unsafe IMO, the one shown is more likely a 1960's item. By the 1970's they had a screw to the cover thus needing a screw driver to access the fuses. If the fuse wire has been unprofessionally replaced various hazards can occur including wrong sized wire and any untidy wiring can leave a bit of live wire sticking out waiting to be touched if the isolator isn’t operated. The after market mcb’s can prevent the fuse cover being fitted leaving the mcb to be pulled or knocked out revealing live brass pins.. The 5amp fuse is generally rated at 1kA breaking capacity which is often less than prospective fault current these days. If there is no supply company isolator the brass main terminals are not fully isolated leaving live uninsulated parts inside This last point alone is sufficient to warrant these awful old fuse boxes to be replaced as you have rightly advised. Hope you don’t mind my chipping in, Good video as always J
What is said is correct of course and a modern consumer unit would be better, but not everyone has the money to pay for the installation. Wired fuses can surge at many times rated current so plugin mcbs with their more accurate trip current are at least better than wired fuses in that way. Rcd sockets for outside appliances such as mowers and power tools and wet appliances such as washing machines can reduce risk of electrocution.
Sweet youtube irony - got an advert for the exact same Wylex MCB's you'd just told people not to bother with come up at the end. Probably no benefit to a sensible consumer but stops people like my brother in law deciding that a blown fuse after attempting to install a new ceiling light* means the existing fuse wire was 'too weak' and needs replacing with something stronger. * he was sure he had that correct - ignore all the previous connections and go with red to red and black to black... right?
Over the years I’ve seen all sorts, bigger wire than should be fitted, screws and nails or the best ones are when people put multiple winds of 5a as it didn’t look strong enough
ben weston No the best ones are when a so called 'professional electrician(s)' (meaning 'electrical' contractor(s)) attend a fault, find that they don't have the correct rated or correct size cartridge fuse, so then 'improvise'. Most of the time wrapping fuse wire or wire stands from flex around the blown cartridge fuse...
how do you stop the cut off switch from springing bk to the off mode.
+jeebas connolly Fix the fault that caused it to trip.
I,ve repkyed on your you tube chanel thanks again and have a good nite now,,
i have an old consumer unit in my home, how easy it is to replace it with a nice one?
difficult and costly
Indeed. Most of the regulations seem designed to generate more work for the trade.
you can get rcd plug in fuse replacements, they must be worth it ?
never seen a RCD plug in fuse replacement
my fuse box started making a horrible vomit-like smell literally out of nowhere. One day nothing, the next it smells. Any advice? (it doesn't smell like burning).
When you've had to fiddle about with a bit of fuse wire (if you can even find any) you'll realise that maybe it wouldn't have been a total waste of money investing in some plug-in MCB's after all
laernulieNlaernulieNlaernulieNNeil Hart So get a new consumer unit. They come with RCD and MCBs as standard.
plug in MCB are a good choice if u can't change your fuse box, rewireable fuses are too unreliable so are the people working on them. They are also to slow. You can try a cartrdge fuse, more precise, but still too slow, so use a MCB , faster, more reliable and can be reset. In the end a new comsumer unit will be the winner.
so if I just wanted to replace the old fuse type to save the pain of me, or my wife who knows nothing about fitting a tiny piece of wire in the dark until I get home to fix the fuse, they are perfect for the job?
Terry Taylor They are certainly much easier to reset than fusewire, however fuses should not need to be replaced regularly.
+John Ward 'Regularly' isn't the issue. The issue is getting a electrician to come out and re-wire a fuse at 2:30AM just because a light bulb took out the CU fuse. Certainly not a waste of money then.
my living room light keeps blowing bulbs the b6 fuse makes a clicking noise could there be something wrong
+John Clark Possibly a loose connection at or near the fuse / circuit breaker, which will cause arcing.
You wouldn't be saying this was a pointless upgrade if you'd seen one of these after my dad bodged new fuse wire in one .. Job got done because I have ... & got done again after moving house for the same reason.