so we'll continue on our lighting circuits wiring diagram and we're developing it further once again
but let's just revisit what we have looked at in previous videos we did a one way lighting circuit
we're using those skills today in order to develop our new drawing we did a two way lighting circuit
two way and intermediate which again we're going to need those skills on today's drawing
and the joint box method so this is our drawing today lots of stuff on here now that we recognize
consumer unit hopefully we recognize that as a one way switch these two here as two way switches
and an intermediate switch and these are ceiling rose and pendants or batten lamp holders
i do recommend you go back and check out those first three stroke four videos with the joint
box one as well there should be a link in the description to download the drawing uh blank
versions for yourself if that link is broken in any way just leave me a message and see if i can
sort it out but at the moment there is a link in the description so you can download these
before you start so let's think about what's going on here one consumer unit in the installation and
we've now not just got one light and one series of switches we've actually got effectively a
couple of rooms here so this light here is controlled one way from this switch here
and then we walk into a separate room where we have another lighting point controlled by three
positions so that's our two way and intermediate switching here so it's a little bit more
developed than we've done before meaning that we've got to work out which terminals we're
using again in our ceiling rose and pendant or batten lamp holder let's just re familiarize
ourselves with the consumer unit all of these here are going to be wiring diagram connections
so where we stick the cable in these accessories here will help you wire it in the real world
however as we've said in the previous four videos the consumer unit itself this is not laid out as
you would actually connect your cables into it but we've got the symbol for a fuse the neutral link
and here where our CPCs will be connected into our earth bar so we're going to use exactly the
same cables as we've used in previous videos we're going to be using one millimeter squared PVC PVC
twin and CPC cables and also because we've got two way and intermediate switching be using our
three core and CPC uh cables again one millimeter squared for us at college often 1.5 in the real
world okay so let's start by bringing a cable from the consumer unit up to our lighting point
remember our lighting point could be something like this so this is our batten lamp batten lamp
holder we've got a series of two connections for our switching line three connections in the
middle for our loop and three connections for our neutral so that's switching line loop and neutral
exactly the same base maybe slightly different laid out but it's just manufacturers change
okay for our ceiling rose and pendant switching line loop neutral okay and that's what we're
representing in these two positions here so cable from the consumer unit is going to come up to our
first lighting point we're using the three plate loop in method in all of the videos we've been
doing so this cable would be here our PVC PVC twin and CPC cable from our consumer unit into
our lighting point itself and if we remember from all the previous videos we must make sure that the
permanent line connection is going to use any of the three connections in the loop remember
this here is just a solid brass block with three holes in it and it wouldn't matter which hole
you went into but you're just going to choose the one that you want to go into so again solid brass
brass block of three wouldn't matter which hole you go into so let's bring the line conductor
up and i'll see if it lines up with any of the holes so i'm going to bring my line conductor up
and it's gone bang straight into the middle one of the loop in terminal so that's my
line conductor i'll bring up my neutral so i've got two and three so this is switching
line and this is neutral so again any of these three could be used as the neutral connection
remember you're probably going to be using a ruler and we're going to our neutral block
and then we've got our CPC this here is our CPC terminal just here is our CPC terminal in our
actual uh pendant or ceiling rose and batten lamp hold up right so let's bring the green one up i'm
just going to kick that one in and as in previous videos i've said sometimes people do like to leave
a little yellow stripe at the side to make it look a little bit more like a CPC so there we have our
first cable a one millimeter squared PVC PVC twin and CPC cable and we've identified the CPC
as we would when we finally connect it with green and yellow sleeving so that's our first cable in
we're going to control it from this switch here so we're going to bring a cable down to here in order
to control this one one way and then we'll develop the circuit over to here in order to do so we're
still going to continue on using our twin and CPC cable remember at Tresham college we're likely to
be using for this part of the circuit a twin brown so this conductor here would be brown and this one
as well as a CPC in industry it's often common to see this twin and CPC cable taken down to a switch
and we have to do something that we've discussed before in the video with the blue conductor when
we're using this to feed from the switch so from the ceiling rose and pendant down to the switch
in this method we're going to need to identify the blue not as neutral as switching line and
that means introducing brown sleeving over the top so we'll draw as a blue conductor and identify it
with brown sleeve because we'll be switching line let's start off by taking the permanent line down
so i'm going to come down out and i'm going to line it up with a common terminal of my one way
switch remember you'll be using a ruler so we come over here we're using a one gang and when we turn
it over we've got common and L1 only that's a blanked off section there so common in L1
that's a one way switch one position can turn on that lighting point so one gang one way switch
so that's what we've got here so brought our line conductor into common we'll bring our neutral no
it isn't remember it's not a neutral it's blue so it won't be coming out of here it's going to
come out of here for a switching line conductor so that's why our students get a little bit confused
when they start connecting up the ceiling rose and pendant in this method that it doesn't always mean
blue is neutral so with that in mind this one here which will be my switching line conductor
and come out of there and it's going to come into L1 so if i bring that out first
we can bring those two up and then we try and make those match okay so if it isn't a neutral i need
to identify it i need to identify it with brown sleeving brown sleeving being that for us it's the
brown pen so i'll just put a strike either side of that one to identify that as a switching line
and same down at the switch itself so in this case this is not a neutral it's a switching line
conductor leaves us now for the CPC CPC terminal here we've got plastic boxes at college so the CPC
is just connected into the back of them often in colleges i've seen online they're actually
using metal boxes on the wall as if that was going to be chopped into the wall and obviously
they're a little bit more robust and break so quickly break a lot of boxes at Tresham college
so if using a metal light switch box there'll be a terminal in the back of it likewise on the plastic
one that we use there'll be a CPC connection in the back of the plastic box leave it long enough
in case we ever change these fronts for metal ones and we'll talk about that as an exposed conductive
part in another video consumer unit to ceiling rose and pendant or batten lamp holder cable down
one millimeter square twin and CPC cable coming down remember the blue is now a switching line
and not a neutral supply comes up to the loop in terminal goes down to the common that's
permanently connected so that's permanently live we close the switch that switching line conductor
comes on to here and we'll energize the lamp so the lamp will have a connection from this side and
a connection from this side they don't need to be coloured sometimes these can be white i've done a
video on that as well but they can be coloured as well so that would go off to what would be
the actual lamp itself so with that in mind we've got a neutral this side
to the lamp and we've got a switching line this side that when we operate the switch we close the
switch we put a line conductor a switching line conductor onto here the lamp will illuminate when
we open the switch we break that line conductor onto here and the lamp will go out so that's
our simple one way lighting circuit repeated but we've now got to bring a cable into the next room
we're gonna bring across a one millimeter squared PVC PVC twin CPC cable from this
lighting point in the first room a cable is going to come across into this room where we could have
any switching arrangement we like but i've chose two way and intermediate switching arrangement
so we need to bring a permanent line into loop we need to bring a neutral into our neutral
connection and a CPC into our earth terminal start with the CPCs first simply bring the CPC across
and connect it to the same terminal inside the ceiling rose and pendant or batten lamp holder
let's go for our neutral take out our neutral and we'll bring that one across gets a little
bit untidy so you'll be very careful where you bring your cables not to show them clashing too
much so if i bring that one through here and we're going to a neutral terminal and then we've got
our permanent line connection out of our loop so we come out of our loop we come across and
we go into our loop terminal like so so what we've got here is this cable here our PVC PVC
one millimeter square twin and CPC cable bringing our line neutral and CPC our permanent line into
loop neutral into our neutral terminal and our CPC into our earth in terminal then we just carry
on down don't we we know what's going to happen next we're going to take this cable down to our
first switch and then we're going to interconnect our remaining switches using our three core cable
so let's just take this one down first so we're gonna bring a brown brown conductor down and we're
gonna bring our um switching line conductor so we've got that blue again that will need to be
identified with brown sleeving so i'm trying to line these up the best i can it won't matter which
one of the two loop in terminals i chose so let's choose this one here so bring that brown into
there that brings my permanent line down i've got blue remember this is not a neutral this
time so it's not coming out of here just because it's the blue pen this time it's a switching line
so we're going to need to identify with brown sleeving so we're going to blue
like so and let's make sure while we're here we identified both sides
so that is actually a switching line and then our CPC CPC comes down and we'll just crack a little
bit of the other on the side so that's what we've done there we've brought our first cable down
so we've brought our switching line a permanent line and CPC down to the first switch exactly
what we've done here we had a one way switch remember we've seen how we can develop a one-way
to a two way and a two way intermediate in those first three videos in this series
we're now going to bring our three core through our system and this caused a lot of controversy
on Instagram when we were looking at this is which colour do people choose as their common connection
we always choose black so we're going to be got a 3 core cable so we're going to have our brown here
connected to our brown here which is our permanent line we're going to have our switching line or the
blue one here connected to grey and black is going to go into common you can choose whichever system
you want if you choose brown as you're common that's great but at college that's what we're
going to do and you can see how the permanent brown one connects also to the brown one in the
three core hence we use black as common so let's bring those colours down now then so we need a
brown black and grey so if i start with my brown brown conductor we'll link through here so what
we're showing here is our two way switch so we've looked at these before so again it's a one gang
two way switch we've got a common doesn't matter where i put it whether it's at the top or the
bottom so we've got a common and then L1 and L2 sometimes they're labeled L1 L2 and L3 but
often that's one on its own it's called common L1 and L2 so we've come out of and it doesn't matter
i said it in the previous demand to come out of L1 or L2 L1 or L2 with this connection here and
then we're going to bring out our grey one out of this one here which will link to our blue so
let's do that next so take our gray so that brings the grey of the three core into here
meaning that we link the black comes out of the common and goes into a connector in the back of
the box or loose in the box we must identify the black and the grey as switching line conductors
the cables between here are often called strappers but we identify them at both ends as switching
line conductors they've got the brown sleeving on so this three core cable here would have the
conductors themselves identified on the grey and on the black with a piece of brown sleeving
so that brings that through to here so our three core cable has gone from our two way
switch our intermediate this section here as i just said is a connection that connection could be
a Wago connector or Wago it could be an Insure connector it could be a through crimp or it
could be a simple connector block and i've done a video on all of those separately on how to connect
those own switches so any of those could have been chosen to join the black to effectively the black
coming down all we're going to do now is take this 3 core cable and repeat it once i've put
the CPC in from here so you can see we've got the CPC to put in and we'll repeat the process down
to our next switch as we did in a previous video so let's take the CPC down from here
and just strike it yellow and complete that cable between the two and then we go again so we'll take
the brown from here at the other side of the switch and we'll have that switch in a minute
we'll take the black let's link the black from here to common we've got our grey conductor
through here so our three core is coming through to our other two way switch
let's not forget it this time the CPC down to there so that puts our other three core cable in
so what we've got here is let's just find this one here what we've got here is our one gang
just this one here one gang intermediate switch two terminals two terminals and we've drawn it
exactly as it would be there top and bottom again they can be labeled L1 L2 L1 L2 or L1 L2 L3 L4
however they're labeled but it's the top two and bottom two and we're going to bring our cables in
from one cable is going to come into the top and the separate cable at the bottom never across the
side so i wouldn't bring the brown and grey from one cable in the side and the brown engraved from
the other in this side you bring in a brown and grey from one cable into the top and now at the
bottom a brown and gray cable from the other cable going down and that's a common mistake people make
when wiring these up and then find when they're testing it it doesn't always turn the light or on
or off it's because you've usually got the connections wrong in your intermediate switch
so let's identify these again with brown sleeving both ends and then what we've got
is our completed wiring diagram for now a more complicated circuit consumer unit
feeding the lighting point which happens to be one way switched a cable taking the supply through to
another room and this time we've got two way and intermediate switching to control this light here
to complete this light all i need to do is put the conductors in that would be connected to the lamp
like so and then depending on the switching position the lamp will either be illuminated
or not so that that's our wiring diagram for a more complicated circuit as i said in the start
of it hopefully you can download all of the drawings in this series of videos from a link
in the description and you can start building up your wired diagrams getting familiar with where
the cables go especially in the intermediate switch again i use black as my common so it's
connected in the connector in the back of the box and i use brown and grey through my actual
intermediate switch as well be careful with the connections on the intermediate switch be careful
with the connections in the intermediate switch the cable comes in the top brown and grey and a
separate cable at the bottom brown and grey real top tip that is so hopefully this um completes
the wiring diagram for a more complicated circuit i'll probably gonna do some more wiring diagrams
maybe looking at the two plate method and wiring in conduit as well but that um pretty much gives
us i think five in this series of videos so far so i'll probably go off and do something
slightly different as always leave you comments below and i hope this video has been some help