today we're looking at classes of electrical conductor
sounds like i'm going back to school gordon
you may well be stay here stay tuned we've got some fun tasks for gary coming up so people ask
why we're making a video about class of conductirs we're actually going to look at is how conductors
are made up in terms of how many strands of copper in there and that's quite important when we return
in some future videos to our favorite topic of ferrule okay so we're going to look at class 1
class 2 class 5 and class 6 conductors and their construction and what makes
them those classes yeah now everyone knows i love a part number nearly as much as i love a
standard and there's nothing like delving into the subtle language that put in a standard and
conductors themselves are covered in bsen 60228 if you're watching from the
from the uk and that is a derivative of an international standard which is iec
60228 thank you very much for clearing that up for us i'll go and delve into those after this video
yeah so you know what do we mean in terms of the class so the class basically refers to how
many strands of copper make up that conductor and the diameter and the number of strands and
the resistance of the conductor are all defined in that standard you probably never ever read it but
you do see it now let's just let's just i'll flip ahead there you do see it if you have a look at a
cable manufacturer's data sheet okay so i can see there that is a class one or class two so let's
take it that when we go above two point five in twin earth cables it becomes solid stranded that's
the point of which you'll be class then is class two yeah and then obviously i flick through and
then obviously flexible cables are always class five okay you'll see them and obviously that's all
types of flexible cable and not to leave our friends out in the security industry federal land
cable is also uh covered in that as well gary okay all right that's good are we going to start off
by just having a little hand cam look at a class one conductor then let's have a little closer look
okay people have seen these time and time again it's incredibly common interestingly this one
here you'd think it was 2.5 it's actually a four millimeter conductor yeah and that was taken out
of an myy cable where the conductors in their solid copper for a lot larger than we're used
to in the uk don't they again bring in the bring the slide the classification obviously
class one is solid conductors as we've said class two is stranded conductors but
both class one and class two are suitable for use in fixed wiring so wiring you'd find in a building
and class five is a flexible conductor as we said and class six i think i had a little bit of input
on this one class six conductors are more flexible than class five just a little bit more flexible so
i think you could argue i had an input there because that makes logical sense to me or in
real real world words they're very flexible and you might see you'll come across them probably
in your daily lives and your test leads and the wire that uh yeah connects up your multi-function
tester so i think gary the first thing just can you count how many conductors are in there there's
seven gordon yeah and this we often use this as our earth and conductor yeah so there's seven
conductors in there making it a little bit more flexible for that fixed wiring situation we've
also got some tails down there and we've got a few more conductors in those aren't they we have let's
have a look at that so again so this is dunk has to make a more flexible version of a meter tail
and obviously that has more individual strands in it but it is still a class two conductor
right okay so so that's clear that we're comfortable i would imagine the electrical
industry seem regularly class one and class two conductors sometimes we don't notice where we
see class five and class six are we going to class five next yeah yeah let's have a look
at the well we've stripped open a class five so let's have a look at what's in there gary okay so
here we go so when we did this we used our week on stripper we've done a review on that
on the channel we have that yeah it's gone down incredibly well so this is a try rated cable
so it should be fine yeah panel wiring things like that where most people would probably see it okay
we'll also identify where we've got it on the desk as well at some point where we actually see it
more often than we think so there we go so that was our fine stranded class five conductor yeah
so i think gary probably uh you know be really useful to know how many strands are
in that actually in that conductor so um i think your best just just can you just count them up
you did so well on the seven core i think really be you know doing a short change and you know
meanwhile while he's doing that i'll just have a little catch up on the old coffee
how was that gary ah yeah terrific absolutely terrific how many strands were in there well
as long as i haven't lost any in the journey over to the chair i got to 122
strands that's a lot of it's a lot of strands more than i thought it would have been in there
yeah i'll go yeah well i counted them so yeah 122. yeah 100 so that's um that's a tri-rated cable but
obviously uh that's same classified conductors are used in flexible cables obviously the bigger the
cables there tends to be more individual strands in there and the maximum diameter of those strands
is defined in our regulation so if I just flick through to that there, you will see that in a
class 5 conductor the 16 millimeter one there you're indeed right gary um there was a lot of
conductors, so it doesn't actually tell you in the standard how many conductors have to be in
there but it does tell you the maximum diameter there can be and it also defines the resistance
of the cable right okay so yeah there's lots of information there probably we wouldn't be you know
day-to-day electricians bothered about but it's actually setting the standards which is really
obviously interesting from this yeah so next game i think we should open up a class six conductor
right let's have a little look inside one of them so again get the weak on stripper out
gotta be really careful with these because they're so finely stranded obviously when
you're dragging down with that blade that you don't catch any of them because they'll
be lost a few in there else so let's see how well you did so we open that up
okay there is a lot of wow there's a lot of strands in there
also mini bundles as well within that cable gordon yeah yeah there we go
again it almost feels like a they're so fine it almost feels like it could be a paintbrush
or something like that and yeah i mean i wonder how many more
in the class five the class i want how many more conductors there are in
a uh in the class six i think well since you you did well on the seven you did well on the five
sing this song again
oh yeah great terrific i don't why i love it you'll be pleased to know gary there isn't a class
seven great okay yeah so interest how many do you find in there i got to 504 but there is always
a chance that one or two of them may have gone missing in the process that's good so again if
we return to our standards of the standard again for that 16 millimeter they are a maximum of 0.21
millimeters each right and again it doesn't define how many that make up that conduct that conductor
but it does define the maximum resistance you have okay so setting the resistance now a little trick
yeah some people might say but we did a video a while ago that looked at fake and substandard
cables and the what the cable we found in there someone had probably shortchanged the customer
and they met a copper that was in there didn't it they did so there wasn't as many strands as
maybe expected so if you've got 504 to go at you missed 10 out would anyone really know exactly
yeah so watch for that one uh if you want a quality control check send the cable through
the gary'll count them for you and send it back but obviously the way to check
is the resistance of the cable because that is defined in the standard that if you've got a
16 millimeter cable its maximum resistance should not be more than 1.2 ohms per kilometer if it's a
class 5 or classics conductor all right that's nice to know then so that should be checked by
the manufacturer shouldn't it so yeah down to those yeah we saw that don cascade we've got a
lab that does all those things now interestingly flexible conductor is actually got just a slightly
higher resistance than solid conductors right so can i just have a little closer look because you
explained that to me standard class ii one that we're very familiar with using actually looks
thinner than the uh class five and class six conductors yeah and you're exactly right gary
there's a millimeter difference in the diameter between these the class two and the class five
and six conductors right okay so again when you're feeling around and you've perhaps gone into a db
and you start filling those uh tails from main switches and that that could be class five or
class six you tend to think they're a little bit bigger than you yeah now again that's defined in
the standard if we have a very quick look at there obviously if we had a solid conductor that would
be smaller again it would be 4.6 millimeters the class 2 is 5.3 and the class five and six
are six point three and they're all the diameters yeah that's all diameters yeah all the same
cross-sectional area for for obviously current carrying capacity things like that but if we
look at our friend of feral here gary this is where it comes in because this is a feral that's
suitable for a 16 millimeter cable right you see it oh well that's loose rattles around on there
whereas if we put it on there it's going to be a challenge challenge there because the insulated
one there that's got a very snug fit to it and we'll revisit that when we look at the topic of
ferrules on these different um different conductor types yeah so we're going to look at the class of
cables and we're going to look whether or not we can or can't ferrel them yeah they're going to be
interesting not it will um so where else might you see them in commonwealth so we had a little
dig around at some of the electrical apparatus so sometimes you'll see a class of cable mentioned
obviously we showed on the cable conductor size itself sometimes you'll see it on switch
gear and things like that but let's have a look at common ones where manufacturers use it so here's a
here's something we've pulled out of a load and consumer unit you can see that's a that is really
flexible so i'm going for the six on that class six conductor definitely i mean you look at if we
just peel back the uh the silicon insulation there you can see yeah that's definitely a definitely a
classic but also took the rcbo at the same board this one here yeah and that seems a little stiffer
yeah again so i think that's a class five and then if you're getting close there gary you can
see there's there's some yeah you can almost you could put you could probably count those straps
yeah i won't be yeah so that looks like yeah class five but then we had a little look at the
latest um afd technology that's wilex one here and again you get close now they've ultrasonically
weld at the end instead of using a ferrule but when you get in close yeah you can see and you
can tell it is very very flexible is it and as they say in the standards it's uh class six is
uh more flexible than class five okay which is uh i like them talking about that yeah that's really
effective that's floppy probably probably why this is more expensive it's absolutely nothing to do
with that it's all those super electronics are in check out the video we made on that where actually
take that to bits and i think you can actually see the conductor in there when we do that so
so that's where you're going to see them so we're used to making off consuming in it so
you wouldn't say necessarily in that consumer unit i've got class one i've got class two but
actually you've got potentially five and six depending on the manufacturer as well
yeah so gordon's worked hard to dig his way through the standards and i'd like to suggest i've
i've worked really hard counting up to really large numbers thank you gordon
but as always we want your feedback especially in this area is there something that you're an
expert on within this field you'd like to add to the comments is there somebody asking a question
that you know the answer to and can you help them with that answer we'd really appreciate
that type of feedback and we will also try and get back to as many comments as we can