As mentioned by others, there's an old rule for ethernet cabling - if they want one cable run two, if two, run quad. In commercial installs quad was always the minimum for my stuff. Cheap in the long run with some redundancy etc for future.
LOVE this. My dad was an electrician and we had dado trunking in our summerhouse built in the 90’s. Multi-way switching for multiple lighting circuits, telephone and coax, plus a switched circuit for lamp sockets. The man was a genius. Our old house had a light switch for the TV socket in the lounge, back when remote controls weren’t a thing.
For data outlets I always run duals. For the little extra cost of running extra data cables with modules its well worth it, even if they don't use it now they are more than likely going to want to in the future.
Cat 7 dual is the only cables I got with me. Sometimes they want a telephone outlet later or just a second outlet for a printer or NAS or so without using a switch
I love the idea of trunking. I used it years ago in a previous house. The only thing I would question is the single Ethernet points. A single back box serves a double point so personally I think it makes more sense to always run double points for all the difference in cost of cable and Cat 6 modules.
It will still work but there is a minimum bend radius on CAT5/6 cables. If we looped back like that on data install and it was inspected by the manufacturer for a warranty they would fail the install. Never going to be a problem on domestic but given dado is pretty common in offices and commercial it should be avoided. Great video as always Nick.
Computers have a fair bit of earth leakage, and there's a reg 543.7.2.201 - if you know there will be more than 10mA leakage per circuit you need to make it a high integrity earth or subdivide circuits further.
I have two sets of the Bosch Robust blue drill bits and they are excellent. However a Bosch guy at Tool Fair told me that it's better not to use percussion with these as the tip geometry is different from a normal masonry bit and percussion blunts them to some extent, so I just use them on rotary and push very hard, which works well. If they don't make much progress then it's time for SDS.
Another way to keep slack on the cat cables in the Dado is to run down the top compartment, then pass the cable through to the bottom compartment and bring it back to the desired location or vice versa
That would prevent you running power in there, as the power and data cables need to be separated by 50mm to meet BS6701 safety requirements(maybe more for BS EN 50173/4, but that’s signal quality, not safety). That’s why dado trunking has two cable paths.
I wouldn’t earth the tray work, it’s not extraneous, it is however an exposed conductive part, BUT the cables being double insulated gives it the same fault and basic protection as any class 2 equipment would have and therefore does not require bonding.
But we would instinctively earth metal back boxes. Please point out where in BS 7671 is says not to bother earthing certain types of exposed conductive parts that could become live under fault conditions, please? Looking forward to your reply!
@@socialscene6361 yes but a metal back box houses single insulated cables so it doesn’t apply in that case. It doesn’t specifically say “don’t earth” them, but regulation 412.2 gives you the requirements for basic protection, then 412.2.4.1 tells you wiring systems such as this one, meet reg 412.2
@@Rick-bb8xc Although, technically if it's a recessed back box then it's not *exposed*... That said GN8 has a note to say “treat them as if they are exposed conductive parts, but a fixed screw lug is sufficient” (paraphrasing)
IT equipment has high earth leakage currents due to their switch mode power supply designs. In some datacenters ive seen them bury a matrix of earth tape directly under the data centre floor to build good earths for the leakage currents to pass to. also maybe its so everything is at an equal potential else u could get bit flips due to floating voltages (likely DC voltages) on the earth if the signals are referenced to ground
Very home-office feeling -- I have Schneider-electric trunk with a bunch of Shuko and RJ45 sockets above it placed above the table surface level. And a dedicated fuse board with RCD in the room. My computer and ham-radio things are isolated from disturbing the rest of the house.
Roughly about 16 mins in, used to do alot of I.T. rooms for schools, main problems used to come when rcd's/RCBO's were first introduced, the old computer's used to "dump" any deleted items down the earth, which would cause nuisance tripping. Great work boys
The dual earth terminals are covered under BS 7671 Section 607 which kicks in when the total protective conductor current is likely to exceed 10 mA - "Where two protective conductors are used in accordance with Regulation 607-02-04 (iii), the ends of the protective conductors shall be terminated independently of each other at all connection points throughout the circuit. e.g. the distribution board, junction boxes and socket-outlets. This requires an accessory to be provided with two separate earth terminals." - on IT Equipment, if you're installing a radial circuit you're supposed to do the earth as a ring. In your case of a small home office, I can't imagine it falls under 607 - but of course Dado Trunking in most commercial places probably would.
Good tutorial - Never knew you could wire it that way so useful information. One point to mention that someone already did is that I would run an extra RJ45 cable for future proof. Surprised customer did not think of that....
As others have mentioned the dual terminals are for high-integrity earthing where over 10ma of leakage is expected on a circuit. With the new amendment to the regs, I believe this is no-longer required instead circuits must be designed/split to have no 10ma of leakage in the first place. The other type is Clean Earth where the CPC on the circuit is connected to one terminal, but the earth pin itself is connected to an isolated terminal that is usually run to a separate electrode. This is normally only used for sensitive equipment that can be affected by other leakage currents in the installation or by earth loops etc. Not very common at all these days apart from specialist situations. There is potential for dangerous voltages during fault conditions to exist between clean and non-clean earth sockets.
It’s called high integrity earthing, as you said you put one CPC in the one terminal and one CPC in the other. You also put them in separate terminals on the earth bar in the consumer unit. You can also have a single protective conductor of no less than 10mm if not in mechanical protection or 4mm if mechanical protection is provided.
I have been involved with several projects involving large quantities of IT equipment (100s computers) and usually requested high integrity earthing (the subcontractors usually used MK) as described above and also due to earth leakage of IT equipment, especially in large quantities.
Dado trunking is a great idea. I'm already planning to do this for my home office. I have a lot of power and data cabling, and it'll make it so much easier to hide it all away.
Circuits with high earthing conductor currents has a little section in the regs. It's done this way to ensure a redundant earth path in the case of a connection point failure. On a ring main the CPC has its own redundant earth path, on a radial circuit like this a second earth path is to be installed. Last time I did this I used armoured cable and metal clad sockets for the secondary earth path.
Just sharing a thought am a level 2 adult student, I would say it requires earthing because it is an exposted part. Its something included in the electrical system and if there was a fault for example rodent damage and someone was trying to fault find. The metal work under fault conditions may become live. I'm just speaking my mind and with what I've learned at college.
Using both earth terminals is only really a thing if you're purposely installing high integrity earthing. So even if you've run a radial, your earth would be a ring. If you'd run a ring you would just use the separate terminal for each cable. For the amount of IT in a home office and especially if that room is on its own radial, it's a non issue.
@@lkchild My generalisation in practical terms: it's required at the point that 19 inch rack cabinets become involved. Freestanding equipment that's plugged into normal socket outlets, in a domestic situation, non issue. An office with many computers and associated ITE, again may be a non issue, the division of circuits would also consider the protective conductor current as well as the loading. And of course, if the mfr's instructions say it needs it, you provide it.
Yes Nick the Catenary Tray should be bonded to earth, should anything compromise the insulation of the cable and there is arcing or contact with the tray. The metal of the tray is at the potential of earth, in case someone comes into contact with the tray while it is energised and they are in contact with earth.
Are you going to put a 'NB Electrical' label/ branding on the front of the mic? Would look awesome. You can also change the brightness of the led's on the mics so they are less obvious.
The metal cable tray is an exposed conductive part of an electrical installation, surely. Therefore, is needs to be earthed. It could become live under fault conditions.
With double insulated cables it requires two faults (both layers of insulation to fail and then make contact with the tray), the argument is that is extremely unlikely...
@@alexacb63 It is unlikely. But if it did happen, that tray would be at live 230 V potential and unknown (no RCD such as distribution circuit) until someone simultaneously touches that and another metalic part at Earth potential - resulting electric shock! Where in BS 7671 does it say not to bother earthing certain types of exposed conductive parts?
@@socialscene6361 I'd recommend watching the eFixx video I posted in another comment. It does come down to whether you consider it likely to become live, if you don't it's not an exposed conductive part. As another example, would you consider a metal cable clip an exposed conductive part, as if it pushed too hard in to the cable and pierced the insulation for example, it could be live, but we never consider earthing those...
@@alexacb63 I see your point. However, in the past I often used to crawl and climb around metal cable tray and metal pipes and extraneous metal parts all simultaneously accessible, whilst working on Hotel refurbs in roof voids etc. I got some comfort from the knowledge that hopefully it'd all be bonded together before grabbing something. I'm not suggesting anybody will be climbing around in Bundy's client's garage, however, that tray is in very close proximity to metal garage doors and such like. I couldn't walk away from that - I'd earth that tray all day long!
@@socialscene6361 that metal garage door likely _isn't_ an extraneous conductive part (although can't say for certain without testing). An extraneous conductive part is something that is liable to introduce a voltage from _outside_ the installation. I would argue the tray is not an exposed conductive part. It's not like it's a metal enclosure containing single-insulated cables or whatever. Id argue that if you're worried about a fault developing during installation then you're probably not testing your installation adequately. If you're worried about a fault developing afterwards during normal use then you've probably selected the wrong installation method for the scenario. So the only argument I can see for bonding a metal tray supporting double insulated cables is to protect against bad design, bad installation and bad testing. Incidentally, metal cable clips are an interesting example when it comes to exposed conductive parts. The regs actually says small objects that can't be easily gripped don't need to be earthed. IIRC it gives faceplate screws as an example. Edit: 410.3.9 “The provision for fault protection may be omitted for the following equipment: iii) exposed-conductive-parts which, owing to their reduced dimensions (approximate maximum of 50 mm x 50 mm) or their disposition cannot be gripped or come into significant contact with a part of the human body and provided that connection with a protective conductor could only be made with difficulty or would be unreliable NOTE: This exemption applies, for example, to bolts, rivets, nameplates, cable clips, screws and other fixings.”
You are correct that when using insulated and sheathed cables, the tray does not need earthing, unless it's being used as a protective conductor, and does not need main bonding, unless it's an extr.c.part. Also, what you were alluding to was that to earth/bond it anyway, could introduce a potential where none would have otherwise existed, so needlessly transit a dangerous potential - see Guidance Note 8 for discussion/details. Re the IT equipment earthing, you could be alluding to equipment with high protective conductor currents, that requires a ring type protective conductor setup, so if one fails/disconnects, the other should stay connected - again, see GN 8 for details.
Only 2 Ethernet sockets..? We fitted 10 in our home office..! You can never have too many Ethernet (or power) sockets..! We fitted 4 double sockets fed from the mains and another three fed from the UPS for the computers. BTW we used Marco Elite Compact trunking which comes pre-drilled for mounting.
On site guide 7.5.3 for earthing of high CPC current (over 10mA) requires connection of sockets at 2 points. This additional protection is required so a break in one point always allows CPC connection from the other.
Can't fault the Bosch blue bits, we use them and there jiggy blades all time, with the amount we cut through we get good use out of the blades.. Tape looks cool, might be worth a look at 👍👍👍👍 Great vid guys, nothing better then getting to site and forgetting something.
2earth terminals were because the power was a radial and the other earth terminal was used for a separate 4.0 mm earth wired as a ring. so that if one came loose there would be a backup
I use to use this many years ago ( no internet then). Or lasers. But for rewires ,in council flats either above skirting or we removed the skirting for sockets .. thinking back now some of the flats looked poor trunking across ceilings walls etc .. you could tell council houses by this most had this done no chasing in and out in a day.
That is clever and so simple of a idea to have a joint right at the beginning of the trunking. when like me you end up having to change an open office around a few times a year that would be such a time saver just make them modular.
Have been swearing by rhe Bosch Blue drill bits for years. Also grabbed a set of those bit holders after seeing them on one of your previous videos Nick, so much better not having to dive to the bottom of my tool bag and inevitably cutting my hand on them now 👍 And on the subject of bags...... Really want to see what the 2nd fix bag looks like 🙏
With Cat cables as a Sparkie just don't run Cat cables along mains 240 cables over long runs as it will cause data loss, talking long runs, 50-80 meters side-by-side. Other one to watch out for is 3-phase big power cables with a bundle of Cat cables passing at a 90' angle, causes packet loss. Believe it or not Cat cable can handle a lot more that people think. Shielded or not I've seen many real work situations where I've been surprises packets are flowing over a Cat cable with zero loss along side massive high voltage stuff... It's all a case of cable length. It's called UTP cable for a reason... Twisted Pair, I'm a techy but a Sparkie would probably understand why it's twisted better than me :)
For datacenters and office buildings the earths have to have separate terminals even in the Distribution Board because computers use the earth to dump electrical noise, if the earth path is ever broken then any metalwork on the computer can have a floating voltage that can be dangerous... this is why its called a functional earth... the more computers plugged in the higher the current flow but for a home office environment it is not really needed provided the house is covered by a PME, if house is protected by TT then I would still use the 2 terminals.
Reason they put into lug on either side is in case one disconnects. Also for radial they run an earth back all the way from the end socket back to the origin. For a ring this happens anyway. if you look at the guidance note for earthing and bonding it's in there. No doubt you know that for an office they would run a seperate dedicated earth and when everything is plugged in you would check no more than 9 maps Dc current on circuit. AC type RCD replaced by A. But you would know that. Again thanks for posting.
8:30 reminds me of the time i was soldering some electronics at my dining room table, in just a pair of shorts and a t-shirt and dropped hot molten solder on my gentlemens area
I agree, there is no point in earthing the tray. Yes it is an exposed conductive part but you are using double insulated cables protected by an rcd. If it was extraneous then yes.
As for the earthing thing, are you talking about a clean earth ? If so you can buy “clean earth” sockets where the 2 lugs don’t actually connect together on the socket. If not, I don’t understand the question 😀🙌🏻
Let's see if I've got this right... "clean earth" is what the Americans call "isolated ground". You carry 2 CPCs through the installation. One is connected as CPC for the installation itself and would as normal loop between parts, this is just as normal. The other is attached *only* to the "equipment ground", or CPC for the earth pin of the socket, therefore also the plug and equipment attached to it. That "clean earth" is carried back directly to your main earthing point (which may or may not be the consumer unit) without being broken or connected to anything else. The "clean" part is that it is supposed to stop any extraneous current that might appear on the CPC reaching and potentially damaging your expensive computer equipment or life saving medial equipment. Actually if it's connected to the main earthing block with everything else then should there be a fault that energises the CPC the so called clean earth is potentially compromised as well. To really work as advertised it needs an entirely separate grounding arrangement and that's a whole other can of worms. I've only ever heard it being discussed in the context of big data centres where we kept the power for computers separate from power for everything else right back to the DNO supply. For domestic? or even small office? Who has time for this s… er… stuff? And right. If that's not what's being talked about I also have no idea why you would connect a CPC to a socket in the way that was being described. It seems to serve no purpose at all and possibly make the CPC connections more fragile than they need to be. Here's Dustin Seltzer explaining isolate ground for Yanks. ua-cam.com/video/kFtv59smv0c/v-deo.html
I think he was referred to high integrity earthing. 453.7 says any circuit where the designer suspects >10mA leakage current should be designed with high integrity earthing. It lists a few ways of doing that; make the CPC a 10mm, run a 4mm CPC in flexi-con, or supply two CPC cables. 543.7.1.204 then says that if you use the third option (two CPC cables) they should each have their own separate terminals at the socket/dist board/etc. 543.7.2 gives a few options specific to socket circuits; the easiest one is just use a ring circuit, but avoid adding spurs...
What's that the dietzel univolt stuff i hate working with that MK much better imo, also I'd earth the tray incase a cable melts through. I also put links where each tray is joined. Potentially it could become live. I'd also recommend cutting lidding with portable bandsaw get a decent cut every time that's square. just have to clean off the swarf.
Not knocking … but even double insulated cables can be effected by vermin , possibility of line in contact with tray High integrity earthing is to always have a cpc connected if one is removed , which becomes a problem if you have run a radial, for the last one. On a ring final the cpc s should be connected to a separate earth block within the db. For domestic high integrity earthing is not an essential , being on your job there are only 2 pc’s which will potentially leak 4-5mA each. It is recommended that no more than 4 PC’s on a 30mA RCD , other than that you good job
Strictly speaking cable isn't double insulated. It's insulated and sheathed. Twin earth terminals is about the possibility of a socket on a ring final circuit where high earth leakage is, or could be, present, losing the connection to earth.
Sure the cable consists of basic insulation and an outer sheath (or jacket). But that outer sheath _is_ rated as a 300/500v insulator. If it wasn't double insulated, then you wouldn't be allowed to install it outside of containment/enclosures.
Efixxx did a good video on bonding tray and basket, might be worth a look. Generally I would bond it but in a domestic setting when it’s not really needed I might not bother
Fair play looks good chap,ain 2 sure of your make theirs loads of different brands..I find MK dado the best 2 use and looks good,it has pre drilled fixing holes 2. Had to use secure metal dado the other day bit of a nightmare never installed that before. Keep up the good work 👍
love the videos!! when you use the chop saw try not to cross your arms likelihood when cutting plastic is it wouldn't happen but cutting timer like that you can do some serious damage to the arm crossing over if the blade bites
I'm pleased to see one of the other reasons Dado is used and that's the natural containment separation of power and data where possible. That being said, less nessacary with the increased insulation on CAT6A, just more difficult to work with and bend. I would a have avoided leaving so much bundled in there though with a tight bend radius. If it was a raised floor office scenario, that's quite common to leave excess as data sockets are being moved all the time as are furniture.
It’s down to the individual install tbh. Warehouse or factory that is all steel, yeah bond. Small section that shouldn’t ever become apart of the system, crack on. If it did, it would be the wrong choice of containment anyway and trunking should of been used.
This may sound stupid, but with regards to having sockets in the correct zones... Would you treat all the sockets in the dado the same as if they were sunk into the wall (each having their own horizontal and vertical zones) I've never seen any dado in a house, and all the offices I've worked in have had dado runs back up to the ceiling tiles. Will the T&E be within 150mm of the corner of the wall? Great video, and yes the Starett holesaws are awesome!
I would be more concerned routing the data cable (if it is unshielded twisted pair, shielded would be fine) than power cables. Computer power supplies are quite robust against all sorts of external influences I think.
There is no risk of cross interference from mains to network, cables the reason for separation is induced voltage in the network cable. Mains cabling 50Hz - Cat 6 upto 500Mhz. Shielded is only needed where there is very noisy RF environments.
Yes that is way to much bend for the network cable. Ideally you would have looped back on the bottom area and then back to the top. Otherwise top job sir! 👍😎
Bend radius is generally 4 time OD of the cable so for Cat 6 / 6a around 4 x 7mm = 28mm, bend Radii, so diameter of loop should be 56mm, Nick's looked tighter than that. That been said unless it was a Certified install its unlikely, in a domestic environment it would matter too much. I doubt it was even a Qualified install, most likely just verified (wire-mapped).
Great job Nick , I do structured cabling in the pharmaceutical industry in ireland and in one of the sites we work in power goes in the bottom and network in the top with nothing in the middle due to standards in the factory. Great work lads keep it up🤙🤙
Liking the microphone sound now Nick … good job .. I do enjoy you’re video’s.. might sound like I was being a mump.. know the case .. just helping your sound issues which helps your videoing and viewers
I was always taught as an apprentice to split the earths between the two earth terminals on dado sockets but was never actually explained as to why and 13 years later I still do it but again have no knowledge as to why 🤣🤷🏻
Dado has cable paths top and bottom for safe separation of power and data. You need to check out BS6701 as a requirement of BS7671 when you’re running data cables. I think you’re a bit close running power cables in the space reserved for boxes, which may be a non compliance.
@@NBundyElectrical Definitely worth using the little wind muffs. They really help cut out the wind noise if you are outside. If you have always got them on then you never forget.
As mentioned by others, there's an old rule for ethernet cabling - if they want one cable run two, if two, run quad. In commercial installs quad was always the minimum for my stuff. Cheap in the long run with some redundancy etc for future.
I'd rather have and not need, than need and not have... Besides, the way I see it is if I'm running 1, I might as well run 4 🤣
Definitely run 4. My single for the TV now has 4 + 5port switch
LOVE this. My dad was an electrician and we had dado trunking in our summerhouse built in the 90’s. Multi-way switching for multiple lighting circuits, telephone and coax, plus a switched circuit for lamp sockets. The man was a genius.
Our old house had a light switch for the TV socket in the lounge, back when remote controls weren’t a thing.
For data outlets I always run duals. For the little extra cost of running extra data cables with modules its well worth it, even if they don't use it now they are more than likely going to want to in the future.
Have always run pairs, got a box of cat 5 why not, always found it saves the ball ache. If dual is requested run a 3rd. Better too much than to little
Cat 7 dual is the only cables I got with me. Sometimes they want a telephone outlet later or just a second outlet for a printer or NAS or so without using a switch
They ask for one you run 2 they want 3, they ask for 2 you run 4 they want 10.
Little tip I found with this hole saws is to cut the plastic in reverse setting of the drill and they will pop out leaving a nice edge.
I love the idea of trunking. I used it years ago in a previous house.
The only thing I would question is the single Ethernet points. A single back box serves a double point so personally I think it makes more sense to always run double points for all the difference in cost of cable and Cat 6 modules.
Yep. We fitted 10 (5 x 2) of them in our home office. Also lots of power sockets, including 3 doubles fed from the UPS for the computer system.
It will still work but there is a minimum bend radius on CAT5/6 cables. If we looped back like that on data install and it was inspected by the manufacturer for a warranty they would fail the install.
Never going to be a problem on domestic but given dado is pretty common in offices and commercial it should be avoided.
Great video as always Nick.
Computers have a fair bit of earth leakage, and there's a reg 543.7.2.201 - if you know there will be more than 10mA leakage per circuit you need to make it a high integrity earth or subdivide circuits further.
I have two sets of the Bosch Robust blue drill bits and they are excellent. However a Bosch guy at Tool Fair told me that it's better not to use percussion with these as the tip geometry is different from a normal masonry bit and percussion blunts them to some extent, so I just use them on rotary and push very hard, which works well. If they don't make much progress then it's time for SDS.
Another way to keep slack on the cat cables in the Dado is to run down the top compartment, then pass the cable through to the bottom compartment and bring it back to the desired location or vice versa
That would prevent you running power in there, as the power and data cables need to be separated by 50mm to meet BS6701 safety requirements(maybe more for BS EN 50173/4, but that’s signal quality, not safety). That’s why dado trunking has two cable paths.
@@lkchild
Use the middle compartment for the 220v cabling and the outer compartments for the low voltage
I wouldn’t earth the tray work, it’s not extraneous, it is however an exposed conductive part, BUT the cables being double insulated gives it the same fault and basic protection as any class 2 equipment would have and therefore does not require bonding.
But we would instinctively earth metal back boxes. Please point out where in BS 7671 is says not to bother earthing certain types of exposed conductive parts that could become live under fault conditions, please? Looking forward to your reply!
@@socialscene6361 yes but a metal back box houses single insulated cables so it doesn’t apply in that case.
It doesn’t specifically say “don’t earth” them, but regulation 412.2 gives you the requirements for basic protection, then 412.2.4.1 tells you wiring systems such as this one, meet reg 412.2
@@socialscene6361 sorry that’s actually in the now, 3 day old blue book, so numbers may have changed now
@@socialscene6361 back boxes have single insulated wires
@@Rick-bb8xc Although, technically if it's a recessed back box then it's not *exposed*... That said GN8 has a note to say “treat them as if they are exposed conductive parts, but a fixed screw lug is sufficient” (paraphrasing)
IT equipment has high earth leakage currents due to their switch mode power supply designs. In some datacenters ive seen them bury a matrix of earth tape directly under the data centre floor to build good earths for the leakage currents to pass to. also maybe its so everything is at an equal potential else u could get bit flips due to floating voltages (likely DC voltages) on the earth if the signals are referenced to ground
This is spot on, and the datacentre earthing is in BS EN 50310 if I remember right.
Very home-office feeling -- I have Schneider-electric trunk with a bunch of Shuko and RJ45 sockets above it placed above the table surface level.
And a dedicated fuse board with RCD in the room. My computer and ham-radio things are isolated from disturbing the rest of the house.
Roughly about 16 mins in, used to do alot of I.T. rooms for schools, main problems used to come when rcd's/RCBO's were first introduced, the old computer's used to "dump" any deleted items down the earth, which would cause nuisance tripping. Great work boys
The dual earth terminals are covered under BS 7671 Section 607 which kicks in when the total protective conductor current is likely to exceed 10 mA - "Where two protective conductors are used in accordance with Regulation 607-02-04 (iii), the ends of the protective conductors shall be terminated independently of each other at all connection points throughout the circuit. e.g. the distribution board, junction boxes and socket-outlets. This requires an accessory to be provided with two separate earth terminals." - on IT Equipment, if you're installing a radial circuit you're supposed to do the earth as a ring.
In your case of a small home office, I can't imagine it falls under 607 - but of course Dado Trunking in most commercial places probably would.
oh thats not what i was expecting , i miss read that title big time !!!! DADO trunking , now i get it !!!
Good tutorial - Never knew you could wire it that way so useful information. One point to mention that someone already did is that I would run an extra RJ45 cable for future proof. Surprised customer did not think of that....
The dual CPC terminals on the back of the socket outlets is something to do with reducing the DC current from IT equipment messing with the RCD's.
Installing trunking alone.
Sit laser on the line for holes not the top or bottom. One screw in at one end and then level the spine.
Easy peasy
As others have mentioned the dual terminals are for high-integrity earthing where over 10ma of leakage is expected on a circuit. With the new amendment to the regs, I believe this is no-longer required instead circuits must be designed/split to have no 10ma of leakage in the first place.
The other type is Clean Earth where the CPC on the circuit is connected to one terminal, but the earth pin itself is connected to an isolated terminal that is usually run to a separate electrode. This is normally only used for sensitive equipment that can be affected by other leakage currents in the installation or by earth loops etc. Not very common at all these days apart from specialist situations. There is potential for dangerous voltages during fault conditions to exist between clean and non-clean earth sockets.
It’s called high integrity earthing, as you said you put one CPC in the one terminal and one CPC in the other. You also put them in separate terminals on the earth bar in the consumer unit.
You can also have a single protective conductor of no less than 10mm if not in mechanical protection or 4mm if mechanical protection is provided.
I have been involved with several projects involving large quantities of IT equipment (100s computers) and usually requested high integrity earthing (the subcontractors usually used MK) as described above and also due to earth leakage of IT equipment, especially in large quantities.
Dado trunking is a great idea. I'm already planning to do this for my home office. I have a lot of power and data cabling, and it'll make it so much easier to hide it all away.
its great because its quick and cheap to add sockets etc , and it doesn't upset the trouble with the decorating being "ruined "
Circuits with high earthing conductor currents has a little section in the regs. It's done this way to ensure a redundant earth path in the case of a connection point failure. On a ring main the CPC has its own redundant earth path, on a radial circuit like this a second earth path is to be installed.
Last time I did this I used armoured cable and metal clad sockets for the secondary earth path.
Just sharing a thought am a level 2 adult student, I would say it requires earthing because it is an exposted part. Its something included in the electrical system and if there was a fault for example rodent damage and someone was trying to fault find. The metal work under fault conditions may become live. I'm just speaking my mind and with what I've learned at college.
Using both earth terminals is only really a thing if you're purposely installing high integrity earthing.
So even if you've run a radial, your earth would be a ring.
If you'd run a ring you would just use the separate terminal for each cable.
For the amount of IT in a home office and especially if that room is on its own radial, it's a non issue.
How do you know? Resilient earthing is needed for high protective conductor current devices, which a lot of modern IT equipment is.
@@lkchild My generalisation in practical terms: it's required at the point that 19 inch rack cabinets become involved.
Freestanding equipment that's plugged into normal socket outlets, in a domestic situation, non issue.
An office with many computers and associated ITE, again may be a non issue, the division of circuits would also consider the protective conductor current as well as the loading.
And of course, if the mfr's instructions say it needs it, you provide it.
Yes Nick the Catenary Tray should be bonded to earth, should anything compromise the insulation of the cable and there is arcing or contact with the tray. The metal of the tray is at the potential of earth, in case someone comes into contact with the tray while it is energised and they are in contact with earth.
Are you going to put a 'NB Electrical' label/ branding on the front of the mic? Would look awesome. You can also change the brightness of the led's on the mics so they are less obvious.
The metal cable tray is an exposed conductive part of an electrical installation, surely. Therefore, is needs to be earthed. It could become live under fault conditions.
With double insulated cables it requires two faults (both layers of insulation to fail and then make contact with the tray), the argument is that is extremely unlikely...
@@alexacb63 It is unlikely. But if it did happen, that tray would be at live 230 V potential and unknown (no RCD such as distribution circuit) until someone simultaneously touches that and another metalic part at Earth potential - resulting electric shock! Where in BS 7671 does it say not to bother earthing certain types of exposed conductive parts?
@@socialscene6361 I'd recommend watching the eFixx video I posted in another comment. It does come down to whether you consider it likely to become live, if you don't it's not an exposed conductive part. As another example, would you consider a metal cable clip an exposed conductive part, as if it pushed too hard in to the cable and pierced the insulation for example, it could be live, but we never consider earthing those...
@@alexacb63 I see your point. However, in the past I often used to crawl and climb around metal cable tray and metal pipes and extraneous metal parts all simultaneously accessible, whilst working on Hotel refurbs in roof voids etc. I got some comfort from the knowledge that hopefully it'd all be bonded together before grabbing something.
I'm not suggesting anybody will be climbing around in Bundy's client's garage, however, that tray is in very close proximity to metal garage doors and such like.
I couldn't walk away from that - I'd earth that tray all day long!
@@socialscene6361 that metal garage door likely _isn't_ an extraneous conductive part (although can't say for certain without testing). An extraneous conductive part is something that is liable to introduce a voltage from _outside_ the installation.
I would argue the tray is not an exposed conductive part. It's not like it's a metal enclosure containing single-insulated cables or whatever. Id argue that if you're worried about a fault developing during installation then you're probably not testing your installation adequately. If you're worried about a fault developing afterwards during normal use then you've probably selected the wrong installation method for the scenario.
So the only argument I can see for bonding a metal tray supporting double insulated cables is to protect against bad design, bad installation and bad testing.
Incidentally, metal cable clips are an interesting example when it comes to exposed conductive parts. The regs actually says small objects that can't be easily gripped don't need to be earthed. IIRC it gives faceplate screws as an example. Edit: 410.3.9 “The provision for fault protection may be omitted for the following equipment: iii) exposed-conductive-parts which, owing to their reduced dimensions (approximate maximum of 50 mm x
50 mm) or their disposition cannot be gripped or come into significant contact with a part of the human
body and provided that connection with a protective conductor could only be made with difficulty or would
be unreliable
NOTE: This exemption applies, for example, to bolts, rivets, nameplates, cable clips, screws and other fixings.”
You are correct that when using insulated and sheathed cables, the tray does not need earthing, unless it's being used as a protective conductor, and does not need main bonding, unless it's an extr.c.part. Also, what you were alluding to was that to earth/bond it anyway, could introduce a potential where none would have otherwise existed, so needlessly transit a dangerous potential - see Guidance Note 8 for discussion/details.
Re the IT equipment earthing, you could be alluding to equipment with high protective conductor currents, that requires a ring type protective conductor setup, so if one fails/disconnects, the other should stay connected - again, see GN 8 for details.
i did that nick , glanding a wired armoured off in crucible theatre sheffield 4 stitches in thigh through two pair of trousers new stanley blade.
Only 2 Ethernet sockets..? We fitted 10 in our home office..! You can never have too many Ethernet (or power) sockets..! We fitted 4 double sockets fed from the mains and another three fed from the UPS for the computers. BTW we used Marco Elite Compact trunking which comes pre-drilled for mounting.
On site guide 7.5.3 for earthing of high CPC current (over 10mA) requires connection of sockets at 2 points. This additional protection is required so a break in one point always allows CPC connection from the other.
Can't fault the Bosch blue bits, we use them and there jiggy blades all time, with the amount we cut through we get good use out of the blades..
Tape looks cool, might be worth a look at 👍👍👍👍
Great vid guys, nothing better then getting to site and forgetting something.
2earth terminals were because the power was a radial and the other earth terminal was used for a separate 4.0 mm earth wired as a ring. so that if one came loose there would be a backup
I use to use this many years ago ( no internet then). Or lasers. But for rewires ,in council flats either above skirting or we removed the skirting for sockets .. thinking back now some of the flats looked poor trunking across ceilings walls etc .. you could tell council houses by this most had this done no chasing in and out in a day.
Awesome job! I would bond it. Just my preference
That is clever and so simple of a idea to have a joint right at the beginning of the trunking. when like me you end up having to change an open office around a few times a year
that would be such a time saver just make them modular.
Have been swearing by rhe Bosch Blue drill bits for years.
Also grabbed a set of those bit holders after seeing them on one of your previous videos Nick, so much better not having to dive to the bottom of my tool bag and inevitably cutting my hand on them now 👍
And on the subject of bags......
Really want to see what the 2nd fix bag looks like 🙏
With Cat cables as a Sparkie just don't run Cat cables along mains 240 cables over long runs as it will cause data loss, talking long runs, 50-80 meters side-by-side. Other one to watch out for is 3-phase big power cables with a bundle of Cat cables passing at a 90' angle, causes packet loss. Believe it or not Cat cable can handle a lot more that people think. Shielded or not I've seen many real work situations where I've been surprises packets are flowing over a Cat cable with zero loss along side massive high voltage stuff... It's all a case of cable length. It's called UTP cable for a reason... Twisted Pair, I'm a techy but a Sparkie would probably understand why it's twisted better than me :)
For datacenters and office buildings the earths have to have separate terminals even in the Distribution Board because computers use the earth to dump electrical noise, if the earth path is ever broken then any metalwork on the computer can have a floating voltage that can be dangerous... this is why its called a functional earth... the more computers plugged in the higher the current flow but for a home office environment it is not really needed provided the house is covered by a PME, if house is protected by TT then I would still use the 2 terminals.
Reason they put into lug on either side is in case one disconnects. Also for radial they run an earth back all the way from the end socket back to the origin. For a ring this happens anyway. if you look at the guidance note for earthing and bonding it's in there. No doubt you know that for an office they would run a seperate dedicated earth and when everything is plugged in you would check no more than 9 maps Dc current on circuit. AC type RCD replaced by A. But you would know that. Again thanks for posting.
8:30 reminds me of the time i was soldering some electronics at my dining room table, in just a pair of shorts and a t-shirt and dropped hot molten solder on my gentlemens area
I agree, there is no point in earthing the tray. Yes it is an exposed conductive part but you are using double insulated cables protected by an rcd. If it was extraneous then yes.
As for the earthing thing, are you talking about a clean earth ?
If so you can buy “clean earth” sockets where the 2 lugs don’t actually connect together on the socket.
If not, I don’t understand the question 😀🙌🏻
Let's see if I've got this right... "clean earth" is what the Americans call "isolated ground".
You carry 2 CPCs through the installation. One is connected as CPC for the installation itself and would as normal loop between parts, this is just as normal.
The other is attached *only* to the "equipment ground", or CPC for the earth pin of the socket, therefore also the plug and equipment attached to it. That "clean earth" is carried back directly to your main earthing point (which may or may not be the consumer unit) without being broken or connected to anything else. The "clean" part is that it is supposed to stop any extraneous current that might appear on the CPC reaching and potentially damaging your expensive computer equipment or life saving medial equipment.
Actually if it's connected to the main earthing block with everything else then should there be a fault that energises the CPC the so called clean earth is potentially compromised as well. To really work as advertised it needs an entirely separate grounding arrangement and that's a whole other can of worms.
I've only ever heard it being discussed in the context of big data centres where we kept the power for computers separate from power for everything else right back to the DNO supply. For domestic? or even small office? Who has time for this s… er… stuff?
And right. If that's not what's being talked about I also have no idea why you would connect a CPC to a socket in the way that was being described. It seems to serve no purpose at all and possibly make the CPC connections more fragile than they need to be.
Here's Dustin Seltzer explaining isolate ground for Yanks. ua-cam.com/video/kFtv59smv0c/v-deo.html
@@calmeilles correct. Commonly used in IT and also sound systems circuits to reduce the “noise”
I think he was referred to high integrity earthing. 453.7 says any circuit where the designer suspects >10mA leakage current should be designed with high integrity earthing.
It lists a few ways of doing that; make the CPC a 10mm, run a 4mm CPC in flexi-con, or supply two CPC cables.
543.7.1.204 then says that if you use the third option (two CPC cables) they should each have their own separate terminals at the socket/dist board/etc.
543.7.2 gives a few options specific to socket circuits; the easiest one is just use a ring circuit, but avoid adding spurs...
Can you get slashproof pants to avoid chopping ya d off? Mines small enough as is.
What's that the dietzel univolt stuff i hate working with that MK much better imo, also I'd earth the tray incase a cable melts through. I also put links where each tray is joined. Potentially it could become live. I'd also recommend cutting lidding with portable bandsaw get a decent cut every time that's square. just have to clean off the swarf.
Not knocking … but even double insulated cables can be effected by vermin , possibility of line in contact with tray
High integrity earthing is to always have a cpc connected if one is removed , which becomes a problem if you have run a radial, for the last one. On a ring final the cpc s should be connected to a separate earth block within the db. For domestic high integrity earthing is not an essential , being on your job there are only 2 pc’s which will potentially leak 4-5mA each. It is recommended that no more than 4 PC’s on a 30mA RCD , other than that you good job
you could have got the new MK screwless terminal sockets and saved fifty quid on a driver ?
Nick nice video on a Saturday morning. Well done on showing some good commercial techniques in a residential setting.
Strictly speaking cable isn't double insulated. It's insulated and sheathed.
Twin earth terminals is about the possibility of a socket on a ring final circuit where high earth leakage is, or could be, present, losing the connection to earth.
Sure the cable consists of basic insulation and an outer sheath (or jacket). But that outer sheath _is_ rated as a 300/500v insulator. If it wasn't double insulated, then you wouldn't be allowed to install it outside of containment/enclosures.
Efixxx did a good video on bonding tray and basket, might be worth a look.
Generally I would bond it but in a domestic setting when it’s not really needed I might not bother
The cables are not double insulated. The do not meet that definition within the regs. They are insulated with out sheath.
The 2 earth terminals allow for high integrity. Effectively as you say you will always have a path to earth if you lose the ring
Fair play looks good chap,ain 2 sure of your make theirs loads of different brands..I find MK dado the best 2 use and looks good,it has pre drilled fixing holes 2. Had to use secure metal dado the other day bit of a nightmare never installed that before. Keep up the good work 👍
love the videos!! when you use the chop saw try not to cross your arms likelihood when cutting plastic is it wouldn't happen but cutting timer like that you can do some serious damage to the arm crossing over if the blade bites
Upgrade opportunity is to add a UPS wiring setup into it and very easy to do at first install stage but profitable ...
Bet Adam never forgot the biscuits ,,,
Should really do even odd wiring on trunking because that fly back cable will not be carrying much current.
Brilliant work and thanks for sharing this with us take care
Good bye Willy 😂 I would have been so sad if that was me. I’m glad your uncut. If you pardon the pun.
Got dado in my office and garage, I’m way ahead of the game.
I looked at putting this is in as already have 3 x double sockets with two 5 socket extension leads so would m e much tidier
I'm pleased to see one of the other reasons Dado is used and that's the natural containment separation of power and data where possible. That being said, less nessacary with the increased insulation on CAT6A, just more difficult to work with and bend.
I would a have avoided leaving so much bundled in there though with a tight bend radius. If it was a raised floor office scenario, that's quite common to leave excess as data sockets are being moved all the time as are furniture.
It’s down to the individual install tbh. Warehouse or factory that is all steel, yeah bond. Small section that shouldn’t ever become apart of the system, crack on. If it did, it would be the wrong choice of containment anyway and trunking should of been used.
Jesus Nick - you nearly had ya plums off there.
This may sound stupid, but with regards to having sockets in the correct zones... Would you treat all the sockets in the dado the same as if they were sunk into the wall (each having their own horizontal and vertical zones) I've never seen any dado in a house, and all the offices I've worked in have had dado runs back up to the ceiling tiles.
Will the T&E be within 150mm of the corner of the wall?
Great video, and yes the Starett holesaws are awesome!
I would be more concerned routing the data cable (if it is unshielded twisted pair, shielded would be fine) than power cables. Computer power supplies are quite robust against all sorts of external influences I think.
There is no risk of cross interference from mains to network, cables the reason for separation is induced voltage in the network cable. Mains cabling 50Hz - Cat 6 upto 500Mhz. Shielded is only needed where there is very noisy RF environments.
Yes that is way to much bend for the network cable. Ideally you would have looped back on the bottom area and then back to the top. Otherwise top job sir! 👍😎
Bend radius is generally 4 time OD of the cable so for Cat 6 / 6a around 4 x 7mm = 28mm, bend Radii, so diameter of loop should be 56mm, Nick's looked tighter than that. That been said unless it was a Certified install its unlikely, in a domestic environment it would matter too much. I doubt it was even a Qualified install, most likely just verified (wire-mapped).
Actually found a use for the beeping level there 👍🏻
淘寶
Any reason why you used metal cable ties opposed to plastic ones?
Great job Nick , I do structured cabling in the pharmaceutical industry in ireland and in one of the sites we work in power goes in the bottom and network in the top with nothing in the middle due to standards in the factory. Great work lads keep it up🤙🤙
Could put the dado trunking On a blue plug ? Literally plug and play
Would I earth the cable tray in that situation , no not necessary. I only earth the tray when I mount electrical accessories on it or light fittings
After the close call with the blade I think it’s only right that after every pee you look at little Nicky and say ‘you a good knob’ 👍🏻
How does cable zoning work with a chase above/below the trunking but not in line with an outlet?
As Big Clive says” cut towards your chum, not your thumb”
I done the same with a electric planer another 5mm would've definitely made me a jaffa
What model pocket Unilight do you use Nick? The folding one. Thanks.
Liking the microphone sound now Nick … good job .. I do enjoy you’re video’s.. might sound like I was being a mump.. know the case .. just helping your sound issues which helps your videoing and viewers
i reckon tray will be earthed with the fixings nick anyway.
I was always taught as an apprentice to split the earths between the two earth terminals on dado sockets but was never actually explained as to why and 13 years later I still do it but again have no knowledge as to why 🤣🤷🏻
lol
在香港都是，因是電流保護方法
@@o0li553 - I appreciate the help but I have no what you’ve just wrote. 😩
@@joeypriestman6783 he said in
"In Hong Kong, because it is a current protection method"
At least according to google translate anyway
How dose cable zoning work with the dado trunking
what an awesome customer.
Will the trunking not compromise the soundproofing?
Dado trucking looks cool and you can hide a whole mess of cable 😂
You measure from the wrong part of the blade. Not the flat but off the teeth as thats the widest part of the blade
0:34 Adam you had one job 😆😆😆
Dado has cable paths top and bottom for safe separation of power and data. You need to check out BS6701 as a requirement of BS7671 when you’re running data cables. I think you’re a bit close running power cables in the space reserved for boxes, which may be a non compliance.
Love the videos but please never ever use a sliding mitre saw cross handed it is unbelievably dangerous.
😂😅😮 cricket Cup bye bye wetting myself on that one 😂😂😂
Haha, I thought Adam put his foot through the ceiling then.
I bet you didn’t buy the trunking at City’s this time 😂
Plenty of pudding on the cables ……… delicious 👌
想問，如果用環型電路2.5mm直徑可以嗎？
I wouldn’t Earth the tray, cables to expensive
Bosh blue bits are the kings of the game 🙌🏻
Video sounds crisp this time 😎
Did you put your foot threw their ceiling
Answered in video
Your audio sounds DELICIOUS!!!
finally
He did only have 1 Mic on
@@AndyK.1But the one Mic was come out of both speaker channels!
@@NBundyElectrical Definitely worth using the little wind muffs. They really help cut out the wind noise if you are outside. If you have always got them on then you never forget.
Sometime these trunkings have a 30A isolator on the end so you can shut the whole lot off in one go
nice work