I do a lot of work in factories with oily atmospheres and we always use plastic oil resistant polymer enclosures for the switch gear. Couple reasons, the oil tends to coat everything and the micro-swarf around can actually cause shorting issues to metal-cased switch gear. Which you don't want in case of a fault ever occurring and not having enough fault current to trip but if it was metal would cause a shock (has happened on a faulty 3 phase CnC before). & two they're a little more robust/safe if something knocks into them as they all have to be at accessible height which is normally hip height - perfect for being knocked by pallet loads or people. Obviously all the consumer units are metal but switch gear is not. Also the way that it is worded all domestic rotary isolators sound like they should be metal instead of plastic?
@@tobysherring1369 If it's single phase for AC/Heat pumps and heating plant it generally would be considered domestic. Yet even 3 phase is plastic so it does make you wonder.
Steel etc enclosures are an *example* of non combustible material. This does not say they are the ONLY way of complying of with this requirement therefore that regulation does not necessarily preclude the use of flame retardant enclosures in carefully considered applications.
@@edc1569 Many plastics have been classed non-combustibles in the past and probably still would be - most domestic fittings are made of a plastic that will only char.
In Europe we only use metal when the board starts getting too big (like a cabinet size as the plastic wouldn’t be sturdy enough) or when IK rating is required, all the rest is plastic as is non conductive and much safer for the basic end user. Most chaseable plastic fuseboards have metal doors though.. If you think of it, the only reason why domestic went for metal DB’s is mainly because of its location under the stairs, in a house made 90% out of wood.. this and too many dummies leaving loose wires behind, originating electrical fires.
yeah we had a number of incidents and the regulators decided rather than tighten up the standards they'd mitigate it by enforcing metal consumer units - I'd rather they did both.
Here in Germany the meter boards are double insulated. Inside everything is covered with plastic, but outer hull is metal. Smaller sub-boards are mostly plastic.
@@Marcel_Germann was used to fibreglass meter boxes for chasing in the wall, plastic for wall mount and metal on the lego style distribution cabinets for the shopping mall shops. In Europe depends on the application, never seen a meter only box in UK.. or even the P100 to receive the dno cable and hold the main fuses.
@@filipe.skunk8 It just a shame they didn't make those fibreglass meter boxes from UV resistant resin, I've seen quite a few that are literally falling apart.
@@paulbritton187 the ones i used back in Portugal were thermoplastic reinforced with fibre glass and the see through bit made of uv resistant polycarbonate.. still last a good 5/10 years depending on sun exposure, but the sun always wins.. have a look if you’re curious, not available here though 😕 www.al-sa.pt/pt-pt/Produtos/StoreCAT/List/0/CategoryID/1028/Level/a
What about incomer tails going into an enclosure for a single RCD for a TT system, them said tails then going into a metal CU? Does the RCD only enclosure need to be plastic?
Since all new domestic distribution switchgear has to be in non-combustible (metal) enclosures, how come mains service isolators (as very thoughtfully installed by some DNOs) are invariably in plastic enclosures?
Given enough pressure and oxygen concentration, steel can auto ignite .. but we are talking hundreds of degrees and hundreds of times the atmospheric pressure.. But let's be fair, the steel igniting at that point is the least of your problems
@@edc1569 and plastic would be better for corrosive chemicals? as I presume GLASS is not an option for that scenario? Do you know where that is in the regs anywhere?
First - I in Jamaica so not all of the BS is relevant locally, and is used mainly as a guideline.. But since we install our panels within the block walls, would have no problem using a plastic box rather than a metal box. Because Concrete is non-combustible
@@brotheradam what I meant was that a plastic box in concrete is probably not going to spread fire...but it's not completely surrounded by concrete. A fire could spread through the plastic cover/lid. That's the point of the reg here in UK.
I wouldn't install a plastic consumer unit in a comercial environment at all. Fire is fire. And the reasons that BS7671 state for installing metal consumer units into a domestic environment can also occur in a small commercial environment. It's about prevention from the risk of fire. Not about what environment it is installed into.
How about inside a salt barn, a facility working with corrosive chemicals? Regulations shouldn't stop engineers making sensible choices about equipment.
A metal enclosure doesn't reduce the risk of fire, it only reduces the risk of fire spread. But if the enclosure is otherwise installed to reduce the risk of fire spread (e.g behind fire doors), and more crucially the installation correctly installed (fire seal) and maintained (reactive maintenance, minor works and periodic inspection and testing carried out competently ) the risk of initial fire, and potential fire spread is significantly lower than that of a poorly installed and maintained installation.
@@edc1569 I worked on an oil rig and also in petro-chemical environments for a while. The equipment used there is different than what is normally used in a normal domestic/industrial installation.
Why is it okay install a metal CU, but have a plastic enclosure stuffed full of Wago jointed cable extensions above/next to it? Is that anyless of a fire risk?
I'm sick and tired of seeing electricians fitting Metal boards in cattle and pig sheds they rot away within a couple of years and the straw and chaff build up is pretty dangerous. Enough said!
So,the whole of rest of Europe is mad to use "plastic"???Of course not!You have "plastic" and plastic!We use a sort of plastic thats hard and not so easy to burn as some other plastics.Fires caused by burning plastic enclosures are very rare indeed.And by the way,the switches in it are plastic!And they can get very warm!No,every european nation has its own regulations about fire hazards.No,it is more like we done it so long so why should we change?
No one is asking you to change, UK buildings are different, a lot of these are installed under the stairs - with a ton of combustible materials nearby (Christmas decorations etc, etc) We've had incidents recently where people have been injured or died from CU fires.
Here in Germany we don't put them in the locations that are usually used in the UK. If you install such a board next to an escape way we also have to use precautions of that kind. For example not using surface mounted boards, using in wall mounted boards with a lid or door with a fire rating of at least F30 with a T30 rated permanent elastic gasket seal. That rating means it could withstand a fire for at least 30 minutes before failing. German regulations for this are the DIN VDE 0100-482 (Fire protection for special risks and dangers) and the DIN VDE 0100-520 (Cable and wire arrangement). Best thing is to have a special room for the boards.
It's not so much about the plastic itself burning, rather that it will deform with the heat and allow fire to spread with relative ease compared to a properly installed metallic enclosure. I have seen several cases now where older consumer units have melted and fire has escaped into wall and ceiling cavities.
@@efixx yeah that's the pc answer, but that reg came about because of the amount of fires in consumer units, and the fact London fire brigade were attending so many fires each week from consumer unit fires, and rather than deal with the cause, the powers that be would rather deal with the symptoms.
I do a lot of work in factories with oily atmospheres and we always use plastic oil resistant polymer enclosures for the switch gear. Couple reasons, the oil tends to coat everything and the micro-swarf around can actually cause shorting issues to metal-cased switch gear. Which you don't want in case of a fault ever occurring and not having enough fault current to trip but if it was metal would cause a shock (has happened on a faulty 3 phase CnC before). & two they're a little more robust/safe if something knocks into them as they all have to be at accessible height which is normally hip height - perfect for being knocked by pallet loads or people.
Obviously all the consumer units are metal but switch gear is not. Also the way that it is worded all domestic rotary isolators sound like they should be metal instead of plastic?
Is a rotary isolator a domestic item?
@@tobysherring1369 If it's single phase for AC/Heat pumps and heating plant it generally would be considered domestic. Yet even 3 phase is plastic so it does make you wonder.
@@tobysherring1369 when it’s installed in a house, definitely. Plenty of domestic dwellings with solar and or heat pumps these days.
Thanks for clearing that up Jo.
Just a follow up question, should The DNO enclosures be of non combustible material in DOMESTIC applications then? 🤔
I believe BS7671 does not apply to DNO's.
They are free to make their own rules up to suit themselves
Steel etc enclosures are an *example* of non combustible material. This does not say they are the ONLY way of complying of with this requirement therefore that regulation does not necessarily preclude the use of flame retardant enclosures in carefully considered applications.
Is flame-retardent the same as non-combustible?
Metal is an 'example' of non-combustible, it says, but it does not say it is the only non-combustible material.
sure, could make a titanium one if you wanted.
@@edc1569 Many plastics have been classed non-combustibles in the past and probably still would be - most domestic fittings are made of a plastic that will only char.
@@edc1569 last time I checked titanium is a metal
In Europe we only use metal when the board starts getting too big (like a cabinet size as the plastic wouldn’t be sturdy enough) or when IK rating is required, all the rest is plastic as is non conductive and much safer for the basic end user. Most chaseable plastic fuseboards have metal doors though.. If you think of it, the only reason why domestic went for metal DB’s is mainly because of its location under the stairs, in a house made 90% out of wood.. this and too many dummies leaving loose wires behind, originating electrical fires.
yeah we had a number of incidents and the regulators decided rather than tighten up the standards they'd mitigate it by enforcing metal consumer units - I'd rather they did both.
Here in Germany the meter boards are double insulated. Inside everything is covered with plastic, but outer hull is metal. Smaller sub-boards are mostly plastic.
@@Marcel_Germann was used to fibreglass meter boxes for chasing in the wall, plastic for wall mount and metal on the lego style distribution cabinets for the shopping mall shops. In Europe depends on the application, never seen a meter only box in UK.. or even the P100 to receive the dno cable and hold the main fuses.
@@filipe.skunk8 It just a shame they didn't make those fibreglass meter boxes from UV resistant resin, I've seen quite a few that are literally falling apart.
@@paulbritton187 the ones i used back in Portugal were thermoplastic reinforced with fibre glass and the see through bit made of uv resistant polycarbonate.. still last a good 5/10 years depending on sun exposure, but the sun always wins.. have a look if you’re curious, not available here though 😕
www.al-sa.pt/pt-pt/Produtos/StoreCAT/List/0/CategoryID/1028/Level/a
Phew thats good 👍👍
What about incomer tails going into an enclosure for a single RCD for a TT system, them said tails then going into a metal CU? Does the RCD only enclosure need to be plastic?
Since all new domestic distribution switchgear has to be in non-combustible (metal) enclosures, how come mains service isolators (as very thoughtfully installed by some DNOs) are invariably in plastic enclosures?
Mine is not in any enclosure. Indoors, next to the meter buried in the wall and surrounded by wood.
Non combustible does not mean metal.
Given enough pressure and oxygen concentration, steel can auto ignite .. but we are talking hundreds of degrees and hundreds of times the atmospheric pressure..
But let's be fair, the steel igniting at that point is the least of your problems
The niceic told me they can be plastic because they are to a different BS EN number than 61439.
Because the DNO and meter fitters work to different rules. They work to the ESQCR not BS7671.
What about Atex rated as well for like if work on a sewage works
So, is there a situation where metal is deemed not-valid for regulations?
Or is it just better all round and nothing beats it ever?
In a commercial environment metal might not be the best choice for a bunch of reasons, handling corrosive chemicals for example.
@@edc1569 and plastic would be better for corrosive chemicals? as I presume GLASS is not an option for that scenario?
Do you know where that is in the regs anywhere?
First - I in Jamaica so not all of the BS is relevant locally, and is used mainly as a guideline.. But since we install our panels within the block walls, would have no problem using a plastic box rather than a metal box. Because Concrete is non-combustible
You don't use a concrete lid/cover though, do you?
@@tobysherring1369 I use conduit and I use the cover the box came with..
@@brotheradam what I meant was that a plastic box in concrete is probably not going to spread fire...but it's not completely surrounded by concrete. A fire could spread through the plastic cover/lid. That's the point of the reg here in UK.
I wouldn't install a plastic consumer unit in a comercial environment at all. Fire is fire. And the reasons that BS7671 state for installing metal consumer units into a domestic environment can also occur in a small commercial environment.
It's about prevention from the risk of fire. Not about what environment it is installed into.
How about inside a salt barn, a facility working with corrosive chemicals? Regulations shouldn't stop engineers making sensible choices about equipment.
A metal enclosure doesn't reduce the risk of fire, it only reduces the risk of fire spread. But if the enclosure is otherwise installed to reduce the risk of fire spread (e.g behind fire doors), and more crucially the installation correctly installed (fire seal) and maintained (reactive maintenance, minor works and periodic inspection and testing carried out competently ) the risk of initial fire, and potential fire spread is significantly lower than that of a poorly installed and maintained installation.
@@edc1569 I worked on an oil rig and also in petro-chemical environments for a while. The equipment used there is different than what is normally used in a normal domestic/industrial installation.
Why is it okay install a metal CU, but have a plastic enclosure stuffed full of Wago jointed cable extensions above/next to it? Is that anyless of a fire risk?
Just use metal enclosures...job done ;-)
I'm sick and tired of seeing electricians fitting Metal boards in cattle and pig sheds they rot away within a couple of years and the straw and chaff build up is pretty dangerous. Enough said!
Can I not use Contactors in a plastic enclosure, In a domestic house?
So,the whole of rest of Europe is mad to use "plastic"???Of course not!You have "plastic" and plastic!We use a sort of plastic thats hard and not so easy to burn as some other plastics.Fires caused by burning plastic enclosures are very rare indeed.And by the way,the switches in it are plastic!And they can get very warm!No,every european nation has its own regulations about fire hazards.No,it is more like we done it so long so why should we change?
No one is asking you to change, UK buildings are different, a lot of these are installed under the stairs - with a ton of combustible materials nearby (Christmas decorations etc, etc) We've had incidents recently where people have been injured or died from CU fires.
Here in Germany we don't put them in the locations that are usually used in the UK. If you install such a board next to an escape way we also have to use precautions of that kind. For example not using surface mounted boards, using in wall mounted boards with a lid or door with a fire rating of at least F30 with a T30 rated permanent elastic gasket seal. That rating means it could withstand a fire for at least 30 minutes before failing.
German regulations for this are the DIN VDE 0100-482 (Fire protection for special risks and dangers) and the DIN VDE 0100-520 (Cable and wire arrangement). Best thing is to have a special room for the boards.
It's not so much about the plastic itself burning, rather that it will deform with the heat and allow fire to spread with relative ease compared to a properly installed metallic enclosure. I have seen several cases now where older consumer units have melted and fire has escaped into wall and ceiling cavities.
That regulation basically means if your a domestic installer you can't be trusted to install insulated boards.
Such an ignorant comment, demonstrated by poor grammar. It's 'you're' not 'your'.
@@beardedsparks2825 what else can it mean, as for the grammar do I care, obviously not 😂
It's more about the environment its installed rather than the installer.
@@efixx yeah that's the pc answer, but that reg came about because of the amount of fires in consumer units, and the fact London fire brigade were attending so many fires each week from consumer unit fires, and rather than deal with the cause, the powers that be would rather deal with the symptoms.
I wonder why they only put it for domestic installations???????????????
so many of them are under staircases in homes in the UK, typically your only way out.
Because there are to many variations in a commercial setting so it’s down to the designer to select the appropriate equipment for the job
Because commercial installations will generally have additional fire hazard protection measures in place.