John Ward, sincerely a big thank you for the content you provide, you have a clean and no-fluff presentation style and you have saved me from electrocuting myself many times. You are a legend in the game 💪🏻
Hi John, simply the best. no additional explanation needed on any of your videos. I wish you were my college lecturer when I was at college, as I did not understand most of what he said it's only years later through practice I realise what he was trying to explain could have been said so much more in a simple and practical way. Good stuff, all the best.
Crickey John, where were you when i was going through my 1-3 C & G Electrical installations courses? . I'm watching your brilliant videos as a refresher .I'm not actually working as an electrician but in the electronics field. I do this as A DIY hobby. Found your approach and guidance more helpful than reading & spending hours at college. I'm watching all your videos , i only wanted a quick refresh on SWA. Cheers. regards Del
Double pole switching seems to be common in mini-RCBO’s available in GB this year. Now it’s arc fault detection (AFD) that fattens up the physical size to two slots wide.. and the price to about £120 for a combined RCBO-AFDD. Still, progress is being made!
It is recommended to use a torque screwdriver now to tighten the breaker terminals . The torque range is now somtimes printed on the side of the MCB/RCBO .
These particularly useful for lights circuit in case of any power trips you it won't effect your lights circuit and won't incomplete dark at night. Which could be hazardous.
RCBO is common in China since 10 years back. Their RCBO has an additional square button to indicate if the trip is due to mcb side or RCB function in the event of a tripping.
This is depending on the manufacturer. I've got one made by ABB, if the RCD-part is tripping it's showing a blue "flag". You can see it here on this pic. If you switch it off manually or you've got overload or short circuit (L to N) the flag will not appear: www.klibo.de/fileadmin/_processed_/b/b/csm_40375243_640_41f6b34423.jpg
John thanks for the video ,you are the only one I who has actually explained what the white wire is for even though briefly.pity you didn't have one that was long enough to connect.as I have seen these grouped together .and I have seen these individually connect to each relative circuit on the earth bar,what is your take on this? thanks
Thank you for making these videos, easy to understand and you take the time explain the terms you are using. I will definitely be using RCBO's for my CU.
In KSA we have adopted the US system that is split phase 220 / 110 what confused me is that in my home panel there is no bonding between earth bus and the nutral bus like most panel in usa in fact the earh bus is isolated from the panel. Does the earth work in this condition. Any explanation
I am in the process of changing the MCB into RCBO. I plan first to measure with a leakage clamp meter each individual circuit. Then if there is see which device is the reason and if it can be adjusted/fixed fix it. Then see the final leakage value and based on that put a 10 or 30mA RCBO in. So, I can finetune each circuit with a 10 or 30mA.
What's your opinion on the merits of SP RCBOs vs DP RCBOs'. I see that Wylex (Siemens) have single width DP RCBOs. Can't see that there are other manufactures providing single width DP RCBOs.
Hi John. I've always wondered why RCBO's functional neutral CSA are all the same size. I would have thought a 50Amp functional neutral would be larger than a 6A. It's most probably a stupid question. Thanks, James.
@@mixer7586 Cost. Someone in China has been shown how to put a blue wire in a plastic box and tighten it up. They have no idea what they are doing, but if they cut 6" of wire and put it in they get paid. You want to introduce half a dozen different wire sizes? Oh no, cheaper and quicker to jut buy one big roll of wire and that will do.
Hi John I started watching your channel about a year ago and all I can say is keep it up excellent, easy plain English description by far the the best on UA-cam . Just got a question what do you think of the lewden populated 14 way consumer unit with rsbo and should I fit spd . Thanks keep up the good work
Hi John, really enjoy your videos. Just wondering what approach do you recomend on say a 3 row CU if the neutral fly lead is to short to reach the neutral bar. Is it acceptable to put ferrule on the fly lead and extend it via a wago connector? Thanks
At 10:15 you talk about the black lead of the RCBO having the end of the wire being welded into a solid piece, how would shortening the wire and soldering the new end of the wire affect the installation?
Does this device work when the 220 is two phase no nutral at all for 220 the old system in ksa is split phase in old houses because I noticed the load side has neutral and l1
Are the narrow RCBOs even available in other countries than UK or IE? In most of Europe you can't get them. My guess is because they are more expensive, contain electronics, and are usually a single pole, so only disconnect the live. The simpler and cheaper double width modules, usually disconnect both L and N, and usually don't contain electronic, and doesn't require extra functional ground.
Not a pin but a bootlace ferrule, as the typical pin is not rated for 32A of current flow. Interesting, as here in South Africa the Heinemann breakers are top entry only, so all the wiring is power in at top and tails at the bottom as opposed to the UK style. Makes for fun with DIN boxes as well, as those RCD devices will not fit here, you need a reversed one.
The normal circuit breakers and RCDs can used in both directions, it doesn't matter if you go in from the upper side and go out on the lower side or the other way arround. Only this style of RCBO demands it to go in from the lower side and go out through the upper side. But standard in Europe is to go into the lower side and go out through the upper side.
John, if you were doing this in your garage for a hybrid inverter, off grid solar. Say you had 2 or 3 rcbo fed circuits, with the functional earth, will it matter if there's a neutral to ground bond or not? I think I want to keep neutral and ground apart due to the grid AC in cable in case of dull days not charging the battery. Any advice greatly appreciated.
Good day John...wanted to ask ..say you need to add just one Rcd and the individual circuits will be with RCBO...will the RCD trip as well as the RCBO (if there is a fault) if they are both 30ma? Thanks
Great video John. Anyway from 9:30 you advice the RCBO's neutral is connected to the main neutral bar and the two RCDs as it were be connected to their own/different neutral bars, reason being it's best the current is kept separate. My question is the main neutral bar, from wiring standards will definitely have to be looped to the other two neutral bars hence the three neutral bars will be at the same potential, so is it really necessary to put each RCD on different neutral bars???????? Again, in the case where you don't have space to add more neutral bars, what do you do then??????
The three neutral bars are at the same potential, the difference is where the wires go before they get there. Both the line and neutral wires for a particular circuit must pass through the RCD. If the neutral was connected directly, the RCD would sense the full load current on the line, nothing for the neutral and trip with any load.
Hello John, fantastic video as usual, Would you agree that another disadvantage of the RCBO is if it trips, how would you know whether it did it due to overload or due to current leakage? Disconnecting faulty consumer (i.e. from the socket) which exhibits either kind of the fault can be only class as a partial success (you can change the consumer) as you still don't know what kind of failure it suffers.How quickly and effectively would you recommend to detect it? Thanks very much, Great collection of videos, Kriss.
Hello John, I live remotely and am prone to power cuts. I have a 4kVA generator to get things running again whenever this happens. My problem is the RCBOs trip as soon as I connect the gen. I've put a good dedicated Earth on the generator but to no avail. I'm considering replacing the RCBOs with MCBs but thought I'd first pick your brains. Peter
Thanks Mr Ward for the helpful video :-) Does the above 1P+N RCBO have differential trip indicator..? Or, is its indicator merely a contact indicator? :-)
Hi John I love your videos. If you get time would you be able to make a video on how to crimp lugs? Especially in things like change over switches which all seem to use bolts as connectors so where you need to use lugs to connect to the bolts.
I've noticed that Wylex CU's have a slightly offset connection for the line busbar at the main switch (and the RCD's for that matter). This is slightly annoying as it means that the busbars must have an end terminal/tab, offset from the rest. Would be nice for all busbar"tabs" to be in a straight line to give more flexibilty in upgrades - e.g. replacing an RCD controlling 3 MCB's with RCBO's means buying another longer busbar to connect to the main switch when the RCD had been replaced by the RCBO's
someone said to me that the top of breakers is the (IN) and the bottom is the (OUT), you here said the opposite, is there a standard to this or polarity doesn't matter in breakers?
John, you forgot to mention if you fit an RCBO alongside RCD's you'll also need to feed a separate live into the bottom and not take it from the busbar otherwise the RCD's trip before the RCBO.
Hi John. Great video as per usual but I have have one niggling question, and that is, are there some ones ashes kept in that urn on the shelf in your office?
A very interesting video on RCBO’s. I am looking at installing a 50A MCB - Type C (not RCD protected) in my current consumer unit and running a 10mm armoured cable to the garage consumer unit. In the garage I intend to install a 6A RCBO - Type B for lights and a 16A RCBO - Type B for a double power socket (no ring, no spur). My question is do I install in my garage consumer unit a 40A - Type C MCB for my EV circuit on the basis the EV circuit has a Matt:e RVD Protection Device that switches both live and neutral circuits and if there is a fault. Also, if I fitted a 40A RCBO it would just fight with the RCD protection in the Matt:e Device and it would just be a toss-up which tripped first?
These rcbo devices create extremely high levels of dirty electricity, in turn creates fibromyalgia increases to the suicide rate, hopefully these devices are phased out in the future just stuck with mcbs
Would it be acceptable to solder the end of that neutral run to make a nice connection to the N bus bar? I have terrible OCD and couldn’t cope with the untidiness of the extra wire.
Do you think it will eventually be standard where everything has to have an RCBO on every circuit? Also just on messy wiring you where talking about , would it not be better practice to have a kind of electrical patch panel similar to what we do in computer networks.Rather than each cable run going right into a circuit breaker or RCBO they go into a terminal block ( similar to the neutral and earth bar ) that way you could replace the consumer unit quickly and easily and re wire it to tidy it without having to mess with the cable runs. You could even pre wire everything off site and simply install it into the runs allowing someone else to do that work that possibly is not trained to mess with the consumer unit. Its done all the time in networking and works very well for reducing time on site and costs for the user. I am surprised consumer units are allowed to be so messy, surly if you have a rats nest of cable going everywhere its hard to tell what your working on , this can lead to dangerous mistakes.
+Andrew Joy Here in Norway you have been required to have 2-pole RCBOs(or 4-pole for 400V 3 phase) for all circuits since 2002. You were allowed to have a single 2-pole RCD (or 4-pole) to protect all your circuits earlier, but all new installations and renovations has to have a RCBO for all circuits.
Here in Germany it's the same. RCDs are necessary for all circuits that are fused with less than 20 A (32 A outside of the house) and are containing a socket that is accessible to electrical laymen. Only one RCD for the whole house is no longer allowed in new installations. This is since 2013, before this in TN-Grids you only needed a RCD in rooms that contained a shower or a bath tub since 1984. Since 2013 the RCBOs are on the rise here in Germany because they need less room in the consumer unit than a cricuit breaker and a RCD. In Germany the AC only RCDs are banned since 1984. The A-type is common, tripping on AC and pulsating current. Last one is necessary due to the increasing usage of switching power supplies.
The patch panel approach is sometimes used in industrial installations, this makes it more modular, easier to route wires, and manufacture and test the entire electric cabinet in the factory to the specified design. But usually it is undesirable, as there is a risk of poor mechanical connection on the patch panel, which is an extra point of failure. So usually it is better to get a circuit wires directly to the RCBO. However, with the invent of more reliable clamp connector blocks, which ensure proper cable clamping, and in more complex installations (so called star installation, where all outlets, fixtures AND switches go to central cabinet, so they can be used also as an automated system) it gets more popular.
Hi John, thanks for the video, I am fitting a new zone 1 bathroom light which requires it to be wired to a 30mA RCD, however there is no space on the consumer unit for another RCD. Am I right in assuming I can replace the current MCB to which the bathroom light is connected with a 30mA RCBO instead of trying to fit an RCD? Many thanks
Yes, provided it will fit in the consumer unit (RCBOs are usually much taller so there may not be space). Another option is to fit an RCD fused spur outside the bathroom for the lighting only, or to fit a separate RCD next to the consumer unit for the lighting circuit - existing MCB - short cable to new RCD - connect to existing lighting circuit.
Hi John thank you for the great video as always. On my older CU the main switch is only single pole which isolates the Line side of the mains supply and the main Neutral in is connected directly to a busbar. There is also and RCCB and a second Neutral busbar both of which are populated. My question is does it matter which of these Neutral busbars i connect the RCBO Neutral to. My RCBO does not have the attached Neutral and Earth wires like the one you used in the video
Yes it does matter - the RCBO connects to the same neutral bar as the rest of the circuit breakers, and not the second one which is only for devices covered by the other RCCB. A single pole main switch is not compliant now, and never was.
Also another question, since i notice those RCDs are rated 63A and are followed in the right case by a B40, B32 and B6 breaker. Is that a safe setup or common setup? Combined they overtake the 63A rating although i know the cases in which you would consume at once 79 amps on a circuit are limited. Also i never saw a 100A breaker, here a single phase house is supplied with 32Amps, you get more only on a three phase setup but that requires a different type of panel
hi just got a couple of cpn rcbo's one problem is that the busbar connection on them is set back from the other breakers how does one compensate for this and the other question does the neutral wire that fits into the rcbo have to be from the circuit or the neutral rail
Is it true you can't just swap an RCBO for an MCB because it would become an unverified assembly? Even if its the same manufacturer? Seems crazy as an RCBO over an MCB should be a huge improvement (if properly tested) whereas the possible risks from tiny differences between parts seems pretty immaterial. 🤔
Consumer units are supplied with enough terminal holes in the neutral bars and often a few spare, so that situation should never happen. However you can buy the bars separately for most consumer units if for some reason you needed more.
Hi Jon, if i want to install all RCBO's in my consumer unit, do i need to keep the RCDs that come with the unit? i've got 19 circuits and want to use a 22 module unit... thanks
I am still learning. I have noticed that grid switches on a commercial unit have 2 different circuits within the switch, I don't like it but get it, I understand that there is a potential for potential difference of 400 volts, and have seen a sticker saying 400 volts on some of these. but can you tell me if or by experiment if 2 different light circuits in the same switch that are on the same phase could you still have a potential for a potential difference of 400 volts.
+journeyonin With a single phase, there will only be 230V between L&E or L&N. With three phases it's still 230V between a single phase and earth or neutral, but 400V between two different phases.
+John Ward Yeah i already understood that, it was more a case of the situation. I will give you another example for instance if i was to measure the voltage between a socket in my house( UK single phase Live) and lets say a light switch Live (same phase) would there be any chance that the potential could rise above 230 volts to 400 volts in potential ( I know there is no reason for ever doing this test.) and realise you have probably already answered it. just don't reply if you already have.
Excellent video, but when a RCBO trips, how do we know which caused the trip, an overload or a leakage? With a separate RCD and MCB at least we know what the problem is. Comments appreciated.
+Tinu Thomas 6000 is the sort circuit capacity (6000 amps), 3 is the energy limiting class, from which the let-through energy in the event of a fault can be obtained.
Hi John. Quick queery . I need to fit a new consumer unit to replace a really ancient one, and to increase the number of circuits from eight to twelve with dual RCDs and RCBO's Due to new building work I am having to resite a new CU about one meter below and to the left of it's existing position. This will make it nessersary to extend the existing circuit cables to the new position. Qu. Can I extend each cable using it's own independent connectors (three /circuit) inside a connection box on the site of the old CU and so extend the existing cables to the new consumer unit. ? Your Advice would be appreciated. Edward Birch
Yes, provided the new cables are in the required zones. If the box remains accessible then any suitable connectors can be used, if not, then they will need to be maintenance free connectors in a box designed for them. It's either RCBOs, or RCD + MCBs, not both.
Hello JW, I think RCBO doesn't cover short circuit protection and just adds overload protection. Some electricians use it instead of RCD and main switch which I doubt is acceptable based on standards.
@@jwflame can rcbos be replaced with mcbs as rcbos do have a live cable and neutral, the circuits would still work removing the neutral and using an mcb circuit breaker?
Air conditioners don't require RCDs / RCBOs unless the manufacturer states they do. The circuit cable may require one, depending on how it's installed.
Interesting - is this legal to DIY? How about adding a 2nd RCD to an existing split load unit? I've got one of those with half the circuits on an RCD and half not, and would be nice to know if I can improve it fairly cheaply.
+81rjp DIY is legal, the only restriction is that some types of work are notifiable to building control in England and Wales. Scotland has a different system. For the split units, the easiest option is to fit RCBOs in place of the MCBs on the non-RCD side and leave the rest as it is.
Ah right, thanks. I knew that replacing a whole consumer unit was notifiable, but the situation for replacing part of one was less clear. As it happens I've checked and it's only lighting circuits (and the alarm) on the non-RCD part, so I'll probably just leave it.
I understand the main advantage of RCBOs that would trip only one circuit. Some apartments have the electricity attached to a distribution box a ground floor but have another distribution box in their apartment. Is is useless to install RCBOs in the apartment if at ground floor is installed an RCD for protection of the wire going up to the apartment?
Submains supplying a consumer unit should not be RCD protected, they should be installed in cables that don't need RCD protection such as armoured, MICC or singles in steel conduit.
Same as for any other circuit - connect the test leads to the RCBO at the consumer unit, or if that's not convenient at some other point on the circuit such as an appliance connection, light fitting, etc.
Someone employ this man to make training videos! Accurate, clear and well thought through.
But his delivery would make me fall asleap......
A man like that could run the country....😊
Mr Ward you have the best teaching voice I have heard in a very long time! Love your videos, very informative, thank you.
The best electrical info on UA-cam, very clear professional and concise
John Ward, sincerely a big thank you for the content you provide, you have a clean and no-fluff presentation style and you have saved me from electrocuting myself many times. You are a legend in the game 💪🏻
Hi John, simply the best. no additional explanation needed on any of your videos. I wish you were my college lecturer when I was at college, as I did not understand most of what he said it's only years later through practice I realise what he was trying to explain could have been said so much more in a simple and practical way. Good stuff, all the best.
john is a great tutor and very easy to understand.
Crickey John,
where were you when i was going through my 1-3 C & G Electrical installations courses? . I'm watching your brilliant videos as a refresher .I'm not actually working as an electrician but in the electronics field. I do this as A DIY hobby. Found your approach and guidance more helpful than reading & spending hours at college.
I'm watching all your videos , i only wanted a quick refresh on SWA. Cheers. regards Del
Double pole switching seems to be common in mini-RCBO’s available in GB this year. Now it’s arc fault detection (AFD) that fattens up the physical size to two slots wide.. and the price to about £120 for a combined RCBO-AFDD. Still, progress is being made!
I never comment but I had to say Exceptional video thank you, explains everything, I can't thank you enough
great video brilliant HD quality. ..And most of all I like your blunt honesty when it comes to cheap crappy anything. ..nice work
It is recommended to use a torque screwdriver now to tighten the breaker terminals . The torque range is now somtimes printed on the side of the MCB/RCBO .
These particularly useful for lights circuit in case of any power trips you it won't effect your lights circuit and won't incomplete dark at night. Which could be hazardous.
Great video and your voice is perfect for explaining things. Thanks
Very Educational and well explained thanks for sharing your knowledge. please continue the good work Mr Ward
RCBO is common in China since 10 years back. Their RCBO has an additional square button to indicate if the trip is due to mcb side or RCB function in the event of a tripping.
This is depending on the manufacturer. I've got one made by ABB, if the RCD-part is tripping it's showing a blue "flag". You can see it here on this pic. If you switch it off manually or you've got overload or short circuit (L to N) the flag will not appear:
www.klibo.de/fileadmin/_processed_/b/b/csm_40375243_640_41f6b34423.jpg
I needed to fit an RCBO filled consumer unit due to lack of space in a small cupboard. I usually fit MCBs, so your video was very helpful = thank you.
'Cheapomatic cu from some diy shed'.......love that, you crack me up John! Have to say your videos are excellent matey, keep them coming!
John thanks for the video ,you are the only one I who has actually explained what the white wire is for even though briefly.pity you didn't have one that was long enough to connect.as I have seen these grouped together .and I have seen these individually connect to each relative circuit on the earth bar,what is your take on this? thanks
Such a good teacher. Will use rcbos for my DIY solar powered pond project.
Well done John, nicely delivered. Thank you.
Thank you for making these videos, easy to understand and you take the time explain the terms you are using. I will definitely be using RCBO's for my CU.
In KSA we have adopted the US system that is split phase 220 / 110 what confused me is that in my home panel there is no bonding between earth bus and the nutral bus like most panel in usa in fact the earh bus is isolated from the panel. Does the earth work in this condition. Any explanation
I am in the process of changing the MCB into RCBO. I plan first to measure with a leakage clamp meter each individual circuit. Then if there is see which device is the reason and if it can be adjusted/fixed fix it. Then see the final leakage value and based on that put a 10 or 30mA RCBO in. So, I can finetune each circuit with a 10 or 30mA.
What's your opinion on the merits of SP RCBOs vs DP RCBOs'. I see that Wylex (Siemens) have single width DP RCBOs. Can't see that there are other manufactures providing single width DP RCBOs.
Brilliant, RCBO's the way to go. thank you Ian
Amazing tutorial and explanation! Thank You!
I can imagine that RCD testing now using an RCBO for every circuit is going to add a lot more time to the complete testing procedures.
I don't think you have to fit RCBO per circuit, nothing stops you to have the RCBO shown here feed 2 or more circuit breakers/circuits after it..
Excellent video as always , clear and easy to understand .
great explanation. why the neutral cable size in the rcbo is smaller than the old RCD?. thanks
Hi John. I've always wondered why RCBO's functional neutral CSA are all the same size. I would have thought a 50Amp functional neutral would be larger than a 6A. It's most probably a stupid question. Thanks, James.
I thought the same as you. Did you get answer to this question yet?
@@mixer7586 Cost. Someone in China has been shown how to put a blue wire in a plastic box and tighten it up. They have no idea what they are doing, but if they cut 6" of wire and put it in they get paid. You want to introduce half a dozen different wire sizes? Oh no, cheaper and quicker to jut buy one big roll of wire and that will do.
Here in Belgium , all RCD's and circuit breakers are dual pole / 3 fase+N in new installations.
Domestic installations in the UK are single phase.
Wonderful explanation, what a great teacher...
Hi John I started watching your channel about a year ago and all I can say is keep it up excellent, easy plain English description by far the the best on UA-cam . Just got a question what do you think of the lewden populated 14 way consumer unit with rsbo and should I fit spd . Thanks keep up the good work
Hi John, really enjoy your videos. Just wondering what approach do you recomend on say a 3 row CU if the neutral fly lead is to short to reach the neutral bar. Is it acceptable to put ferrule on the fly lead and extend it via a wago connector? Thanks
Great explanation especially your discussion of functional earths.
At 10:15 you talk about the black lead of the RCBO having the end of the wire being welded into a solid piece, how would shortening the wire and soldering the new end of the wire affect the installation?
Does this device work when the 220 is two phase no nutral at all for 220 the old system in ksa is split phase in old houses because I noticed the load side has neutral and l1
The type shown in the video does not, they are designed for systems where the neutral and earth (via the white lead) are at the same potential.
Are the narrow RCBOs even available in other countries than UK or IE? In most of Europe you can't get them. My guess is because they are more expensive, contain electronics, and are usually a single pole, so only disconnect the live. The simpler and cheaper double width modules, usually disconnect both L and N, and usually don't contain electronic, and doesn't require extra functional ground.
Thank-you John. Ended up here because i was curious about what the white wire did.
What a guy! Brilliant teacher, subbed!
Great video as usual. Could we have a follow up video on testing with RCBO's?
Hi J W nice channel, could you shorten the black cable and add a bootlace ferrule or would that be contravening the IEEE Regs?
Not a pin but a bootlace ferrule, as the typical pin is not rated for 32A of current flow.
Interesting, as here in South Africa the Heinemann breakers are top entry only, so all the wiring is power in at top and tails at the bottom as opposed to the UK style. Makes for fun with DIN boxes as well, as those RCD devices will not fit here, you need a reversed one.
The normal circuit breakers and RCDs can used in both directions, it doesn't matter if you go in from the upper side and go out on the lower side or the other way arround. Only this style of RCBO demands it to go in from the lower side and go out through the upper side. But standard in Europe is to go into the lower side and go out through the upper side.
John, if you were doing this in your garage for a hybrid inverter, off grid solar. Say you had 2 or 3 rcbo fed circuits, with the functional earth, will it matter if there's a neutral to ground bond or not? I think I want to keep neutral and ground apart due to the grid AC in cable in case of dull days not charging the battery. Any advice greatly appreciated.
i assume somewhat like a GFI/ AFCI type breaker used in the US. it is interesting that on the UK breakers is more markings of what is going on.
Good day John...wanted to ask ..say you need to add just one Rcd and the individual circuits will be with RCBO...will the RCD trip as well as the RCBO (if there is a fault) if they are both 30ma? Thanks
Great video John.
Anyway from 9:30 you advice the RCBO's neutral is connected to the main neutral bar and the two RCDs as it were be connected to their own/different neutral bars, reason being it's best the current is kept separate.
My question is the main neutral bar, from wiring standards will definitely have to be looped to the other two neutral bars hence the three neutral bars will be at the same potential, so is it really necessary to put each RCD on different neutral bars????????
Again, in the case where you don't have space to add more neutral bars, what do you do then??????
The three neutral bars are at the same potential, the difference is where the wires go before they get there. Both the line and neutral wires for a particular circuit must pass through the RCD. If the neutral was connected directly, the RCD would sense the full load current on the line, nothing for the neutral and trip with any load.
Well noted.
Can you please do a video on the construction/building of an Automatic Transfer Switch (ATS)?
Bigclivedotcom has done one on those:-
ua-cam.com/video/babtv00R-Nc/v-deo.html
Hello John, fantastic video as usual,
Would you agree that another disadvantage of the RCBO is if it trips, how would you know whether it did it due to overload or due to current leakage?
Disconnecting faulty consumer (i.e. from the socket) which exhibits either kind of the fault can be only class as a partial success (you can change the consumer) as you still don't know what kind of failure it suffers.How quickly and effectively would you recommend to detect it?
Thanks very much,
Great collection of videos,
Kriss.
krisbham probably own multimeter would enable individual power points or lighting circuit testing for megohm readings.
@@austin1722 not much use for the homeowner... 😒
without testing equipment I think there's no way to know. however both problems would require the same solutions implemented anyway, right?
Hello John, I live remotely and am prone to power cuts. I have a 4kVA generator to get things running again whenever this happens. My problem is the RCBOs trip as soon as I connect the gen. I've put a good dedicated Earth on the generator but to no avail. I'm considering replacing the RCBOs with MCBs but thought I'd first pick your brains. Peter
How are you changing between Generator and Grid Supply, Peter? Changeover Switch?
Type Cs may help. designed for use with motors. Anyone care to comment?
Thank you for taking the effort to share this. it was very helpful
Hi John. Good video. I just want to add a circuit breaker. It's a new CU and there is space for additions. Can you advise me?
Thanks Mr Ward for the helpful video :-)
Does the above 1P+N RCBO have differential trip indicator..?
Or, is its indicator merely a contact indicator? :-)
Hi John I love your videos. If you get time would you be able to make a video on how to crimp lugs? Especially in things like change over switches which all seem to use bolts as connectors so where you need to use lugs to connect to the bolts.
I've noticed that Wylex CU's have a slightly offset connection for the line busbar at the main switch (and the RCD's for that matter). This is slightly annoying as it means that the busbars must have an end terminal/tab, offset from the rest. Would be nice for all busbar"tabs" to be in a straight line to give more flexibilty in upgrades - e.g. replacing an RCD controlling 3 MCB's with RCBO's means buying another longer busbar to connect to the main switch when the RCD had been replaced by the RCBO's
Be awsome if u showed installed a whole fuse box to a house or unit
Hi John,
How do you do inspect & test an RCBO.
someone said to me that the top of breakers is the (IN) and the bottom is the (OUT), you here said the opposite, is there a standard to this or polarity doesn't matter in breakers?
I thank you alot john to this fantastic & great video
Hello..
Can you make a video on what happens to the neutral cable goes back to the substation or whatever in detailed.
Nice one JW, explained perfectly
John, you forgot to mention if you fit an RCBO alongside RCD's you'll also need to feed a separate live into the bottom and not take it from the busbar otherwise the RCD's trip before the RCBO.
Thanks to John and Mark for their advice.
This is what I was thinking, how is that done?
Informative video and well presented. 👍
When you have RCD's and RCBO's in the same board how do you deal with the live into the devices?
Hi John. Great video as per usual but I have have one niggling question, and that is, are there some ones ashes kept in that urn on the shelf in your office?
It's empty, no ashes there or anywhere else.
A very interesting video on RCBO’s. I am looking at installing a 50A MCB - Type C (not RCD protected) in my current consumer unit and running a 10mm armoured cable to the garage consumer unit. In the garage I intend to install a 6A RCBO - Type B for lights and a 16A RCBO - Type B for a double power socket (no ring, no spur).
My question is do I install in my garage consumer unit a 40A - Type C MCB for my EV circuit on the basis the EV circuit has a Matt:e RVD Protection Device that switches both live and neutral circuits and if there is a fault. Also, if I fitted a 40A RCBO it would just fight with the RCD protection in the Matt:e Device and it would just be a toss-up which tripped first?
These rcbo devices create extremely high levels of dirty electricity, in turn creates fibromyalgia increases to the suicide rate, hopefully these devices are phased out in the future just stuck with mcbs
Would it be acceptable to solder the end of that neutral run to make a nice connection to the N bus bar? I have terrible OCD and couldn’t cope with the untidiness of the extra wire.
No, solder is too soft to use under screw terminals, it tends to flow under pressure which results in a loose connection.
Do you think it will eventually be standard where everything has to have an RCBO on every circuit?
Also just on messy wiring you where talking about , would it not be better practice to have a kind of electrical patch panel similar to what we do in computer networks.Rather than each cable run going right into a circuit breaker or RCBO they go into a terminal block ( similar to the neutral and earth bar ) that way you could replace the consumer unit quickly and easily and re wire it to tidy it without having to mess with the cable runs. You could even pre wire everything off site and simply install it into the runs allowing someone else to do that work that possibly is not trained to mess with the consumer unit. Its done all the time in networking and works very well for reducing time on site and costs for the user.
I am surprised consumer units are allowed to be so messy, surly if you have a rats nest of cable going everywhere its hard to tell what your working on , this can lead to dangerous mistakes.
+Andrew Joy Here in Norway you have been required to have 2-pole RCBOs(or 4-pole for 400V 3 phase) for all circuits since 2002. You were allowed to have a single 2-pole RCD (or 4-pole) to protect all your circuits earlier, but all new installations and renovations has to have a RCBO for all circuits.
Here in Germany it's the same. RCDs are necessary for all circuits that are fused with less than 20 A (32 A outside of the house) and are containing a socket that is accessible to electrical laymen. Only one RCD for the whole house is no longer allowed in new installations. This is since 2013, before this in TN-Grids you only needed a RCD in rooms that contained a shower or a bath tub since 1984. Since 2013 the RCBOs are on the rise here in Germany because they need less room in the consumer unit than a cricuit breaker and a RCD.
In Germany the AC only RCDs are banned since 1984. The A-type is common, tripping on AC and pulsating current. Last one is necessary due to the increasing usage of switching power supplies.
Here in the United States, because we usually don't use whole-home RCDs we use RCBOs or RCDs integrated into outlets as needed.
The patch panel approach is sometimes used in industrial installations, this makes it more modular, easier to route wires, and manufacture and test the entire electric cabinet in the factory to the specified design. But usually it is undesirable, as there is a risk of poor mechanical connection on the patch panel, which is an extra point of failure. So usually it is better to get a circuit wires directly to the RCBO. However, with the invent of more reliable clamp connector blocks, which ensure proper cable clamping, and in more complex installations (so called star installation, where all outlets, fixtures AND switches go to central cabinet, so they can be used also as an automated system) it gets more popular.
Hi John, thanks for the video, I am fitting a new zone 1 bathroom light which requires it to be wired to a 30mA RCD, however there is no space on the consumer unit for another RCD. Am I right in assuming I can replace the current MCB to which the bathroom light is connected with a 30mA RCBO instead of trying to fit an RCD?
Many thanks
Yes, provided it will fit in the consumer unit (RCBOs are usually much taller so there may not be space).
Another option is to fit an RCD fused spur outside the bathroom for the lighting only, or to fit a separate RCD next to the consumer unit for the lighting circuit - existing MCB - short cable to new RCD - connect to existing lighting circuit.
Why don't RCBOs use a neutral busbar instead of fly leads? what am i missing?
Hi .. I have only just seen your series of videos. I wish I had these when I was doing my 2391. Thanks
can you run two radial circuits on the one rcbo?
Sir please tell how to check a original hager MCB? because in the market many seller sells duplicate MCB's with the mark of Hager
"El Cheapo"... brilliant, I'm using that one 😁
Hi John thank you for the great video as always. On my older CU the main switch is only single pole which isolates the Line side of the mains supply and the main Neutral in is connected directly to a busbar. There is also and RCCB and a second Neutral busbar both of which are populated. My question is does it matter which of these Neutral busbars i connect the RCBO Neutral to. My RCBO does not have the attached Neutral and Earth wires like the one you used in the video
Yes it does matter - the RCBO connects to the same neutral bar as the rest of the circuit breakers, and not the second one which is only for devices covered by the other RCCB.
A single pole main switch is not compliant now, and never was.
@@jwflame Thank you very much John for your reply and clarification , Always enjoy your videos keep up the great work.
Any reason for the pigtails on some RCBOs?
Also another question, since i notice those RCDs are rated 63A and are followed in the right case by a B40, B32 and B6 breaker. Is that a safe setup or common setup? Combined they overtake the 63A rating although i know the cases in which you would consume at once 79 amps on a circuit are limited. Also i never saw a 100A breaker, here a single phase house is supplied with 32Amps, you get more only on a three phase setup but that requires a different type of panel
Safe and very common - it's the actual loads which matter, not the rating of the individual devices.
Another superb video John,
regarding not shortening the neutral lead on the RCBO, Is it ok to shorten then fit a Ferrule?
ooops... you answered the question at 11min 30sec
What a great video, thank you 🙏🏻
hi just got a couple of cpn rcbo's one problem is that the busbar connection on them is set back from the other breakers how does one compensate for this and the other question does the neutral wire that fits into the rcbo have to be from the circuit or the neutral rail
If the busbar isn't in the right place, they are the wrong devices.
Hi John what is your take on trimming down the neutral fly lead or should it be left original length
Can be cut, but if so it will need a terminal crimped on the end, as the wires used are normally very fine ones.
@@jwflame hi John thanks have got a few bg ones and the leads are massive. So just put a boot lace ferrel type crimp on
Is it true you can't just swap an RCBO for an MCB because it would become an unverified assembly? Even if its the same manufacturer? Seems crazy as an RCBO over an MCB should be a huge improvement (if properly tested) whereas the possible risks from tiny differences between parts seems pretty immaterial. 🤔
Hi John a great video what happens if you have more rcbo than the main neutral bar holds
Consumer units are supplied with enough terminal holes in the neutral bars and often a few spare, so that situation should never happen. However you can buy the bars separately for most consumer units if for some reason you needed more.
@@jwflame thank you
We tend to fit these as rcbos most customers instantly see the benefits
Hi Jon,
if i want to install all RCBO's in my consumer unit, do i need to keep the RCDs that come with the unit?
i've got 19 circuits and want to use a 22 module unit... thanks
No, an RCBO is an RCD and MCB in the same device.
You need a consumer unit with a main switch and as many RCBOs as required.
I am still learning. I have noticed that grid switches on a commercial unit have 2 different circuits within the switch, I don't like it but get it, I understand that there is a potential for potential difference of 400 volts, and have seen a sticker saying 400 volts on some of these. but can you tell me if or by experiment if 2 different light circuits in the same switch that are on the same phase could you still have a potential for a potential difference of 400 volts.
+journeyonin With a single phase, there will only be 230V between L&E or L&N. With three phases it's still 230V between a single phase and earth or neutral, but 400V between two different phases.
+John Ward Yeah i already understood that, it was more a case of the situation. I will give you another example for instance if i was to measure the voltage between a socket in my house( UK single phase Live) and lets say a light switch Live (same phase) would there be any chance that the potential could rise above 230 volts to 400 volts in potential ( I know there is no reason for ever doing this test.) and realise you have probably already answered it. just don't reply if you already have.
Best electrician on the land
Worst electrition on earth rcbo create extreme dirty electricity
I have one of those (B6) with a rather short earth lead. Can I safely extend this wire and fit the breaker into another CU?
+Mik G Yes, wire can be extended if too short.
Excellent video, but when a RCBO trips, how do we know which caused the trip, an overload or a leakage? With a separate RCD and MCB at least we know what the problem is. Comments appreciated.
On most you don't. Some have a mechanical indicator to show whether it was due to the MCB or RCD part, but that isn't common.
@@jwflame Perhaps it could be made compulsory on RCBOs to have separate indicators in the 18th First amendment...? There's bound to be one!
@@John2E0GTU high ka can trip the rcbo they also cause dirty electricity I eat the radation from the rcbo so I'm all good
Thx
For sharing your knowledge.....
Really helpful .
nice video.
what about the values written in boxes (6000 & 3) in front of RCBO?
+Tinu Thomas 6000 is the sort circuit capacity (6000 amps), 3 is the energy limiting class, from which the let-through energy in the event of a fault can be obtained.
Does it matter which side of main switch is used for the live and the neutral ?
No, both sides are the same - but it does matter inside the consumer unit, L must connect to the busbar and N to the neutral bar
Hi John. Quick queery . I need to fit a new consumer unit to replace a really ancient one, and to increase the number of circuits from eight to twelve with dual RCDs and RCBO's Due to new building work I am having to resite a new CU about one meter below and to the left of it's existing position. This will make it nessersary to extend the existing circuit cables to the new position. Qu. Can I extend each cable using it's own independent connectors (three /circuit) inside a connection box on the site of the old CU and so extend the existing cables to the new consumer unit. ? Your Advice would be appreciated. Edward Birch
Yes, provided the new cables are in the required zones. If the box remains accessible then any suitable connectors can be used, if not, then they will need to be maintenance free connectors in a box designed for them.
It's either RCBOs, or RCD + MCBs, not both.
Many thank John.
Hello JW, I think RCBO doesn't cover short circuit protection and just adds overload protection. Some electricians use it instead of RCD and main switch which I doubt is acceptable based on standards.
Rcbos don't help with short circuit all they do is increase dirty electricity the test buttons only make it worse
RCBOs cover short circuit, moderate overloads and current imbalance. It's the same protection as a separate circuit breaker and RCD.
@@jwflame can rcbos be replaced with mcbs as rcbos do have a live cable and neutral, the circuits would still work removing the neutral and using an mcb circuit breaker?
great videos. very helpful thank you. you make a great teacher.
Nice video ,is RCBo require for AC 1.5Ton in Uk?
Air conditioners don't require RCDs / RCBOs unless the manufacturer states they do. The circuit cable may require one, depending on how it's installed.
Thank you for the demonstration,
Thank you John very well explained.
Interesting - is this legal to DIY? How about adding a 2nd RCD to an existing split load unit? I've got one of those with half the circuits on an RCD and half not, and would be nice to know if I can improve it fairly cheaply.
+81rjp DIY is legal, the only restriction is that some types of work are notifiable to building control in England and Wales. Scotland has a different system.
For the split units, the easiest option is to fit RCBOs in place of the MCBs on the non-RCD side and leave the rest as it is.
Ah right, thanks. I knew that replacing a whole consumer unit was notifiable, but the situation for replacing part of one was less clear. As it happens I've checked and it's only lighting circuits (and the alarm) on the non-RCD part, so I'll probably just leave it.
I understand the main advantage of RCBOs that would trip only one circuit. Some apartments have the electricity attached to a distribution box a ground floor but have another distribution box in their apartment. Is is useless to install RCBOs in the apartment if at ground floor is installed an RCD for protection of the wire going up to the apartment?
Is there a way to go round this to install RCBOs? Thanks for your educational clips. They are really useful. Thanks again.
Submains supplying a consumer unit should not be RCD protected, they should be installed in cables that don't need RCD protection such as armoured, MICC or singles in steel conduit.
@@jwflame Thanks for taking time to answer my query and of course provide a solution. Great man,
What's the correct procedure for testing the trip times of RCBO for radial circuits without sockets? Cheers.
Same as for any other circuit - connect the test leads to the RCBO at the consumer unit, or if that's not convenient at some other point on the circuit such as an appliance connection, light fitting, etc.
I would recommend the furthest point from the consumer unit on the circuit on which you'll perform your testing.