so in this video presentation we can look for the connections for converting a one-way lighting
circuit so in other words you walk into a room let's say ceiling rose and pendant or batten
lamp holder and there is one switch that will turn on and off that light we're going to look how we
can convert that to have control via two positions by converting it to two ways switching we can see
the current switch drop down from the ceiling rose is in blue brown and green and yellow so
we've got twin and CPC cable we remember from a previous presentation that the blue is not
a neutral and is a switching line conductor and is identified with brown sleeving both ends and
we bring down a permanent line connection the brown conductor which is connected in common
on operating the switch if it's a switching line conductor through to L1 and will turn on the lamp
in the room remember that the switch drop could be in twin brown therefore both conductors are
identified already and no sleeving is required or in old colours we could be in red and black
with the black one identified with red sleeving or it could be in twin red the cable that does
come down to the switch drop whichever of the four described it is in this case it's twin and
CPC remains in place however the switch which is a one-way switch will need to be removed we will
also need to add a cable in from this switching point to the new switching point in the room and
we will need to put two way switches is in both locations so this will have a two-way switch
replacing the one-way at the original position and the new position within the room we'll also
have a two-way switch I see what that looks like while we add the cabling and obviously we replace
this switch and add a new switch in the switch shown at the top of this presentation is the one
that we originally showed in the first part of the presentation and still has the cable being a
twin and CPC coming into it the new cable that's been introduced to link together the two switch
positions is a three core and CPC we said in the first part of the presentation when adding an
additional switching point we would have to change the switch from a one-way switch to a two-way
switch we can see that both switches are two ways switches comprising of common L1 and L2 so let's
have a look at the terminations that are going to be made in our original switched position at the
top now but with a two way switch my original twin and CPC cable now is connected brown conductor in
L1 and my blue conductor with brown sleeving in L2 it wouldn't matter if they were the other way
around but that's what it's shown in the drawing we've introduced the three core and CPC to link
together this two-way switch with a new two-way switch position the terminations as I would do
at college use black for common identified also with browns sleeving because it's a switching
line conductor my brown goes in L1 and my grey conductor of the three core goes in L2 when we
look at the bottom switch position as long as we have the correct cable in common and I've
used black for common and it's shown in the common position with browns sleeving it wouldn't matter
if I have the brown conductor going in L2 or L1 and the grey conductor going L1 or L2 makes no
difference in this switching configuration however you can see in the drawing I've kept it exactly
the same using brown in L1 and a grey conductor identified with brown sleeving in L2 I've now
got to control from two different positions from my original lighting point so I've added another
switch in order to add another switch I've added a three core CPC cable from my original switch
position to my new switch position I've replaced the front which was originally a one-way switch
with a two-way switch and the second switch also has a two-way switch at its position so with this
new configuration I have control over my lighting point from now two positions I can turn it on and
off from two different positions within the same room in the final part of this presentation we're
going to look how we could introduce a third switch making the switching arrangement two
way and intermediate so let's look at two-way an intermediate switching for all intents and
purposes it looks as if we've just added a switch in the center here however if we two-way switching
as we did in our previous draw and I discussed it would actually be the bottom switch that we've now
added in we extended it to be three switches if we look at the top switch it's still fed with a
twin and CPC cable and still has a three core and CPC going on to the next switch position
and still is a two-way switch the three core feeds into our second switch positions did before we've
added another three core cable from that position down to what would be our new switch position at
the bottom and we've had to replace the center switch from a two-way switch and our previous
two-way drawings now to be an intermediate switch the two ways which appears at the end so at the
bottom switch now which is fed from a three core from the switch above is a two-way switch so in
real terms from the drawing which just looked at the two ways which has moved down a position to in
the bottom in order to have to way in intermediate switching the first which is a two-way switch you
can have as many intermediate switches as you'd like I've only shown one in this drawing and then
followed by a final two-way switch so we could have shown twenty intermediate switches as long
as the first which is a two-way and the last which was a two-way let's have a look at the
connections in each of the switches now so let's have a look at the connections in the top switch
which are identical to one shown in the previous drawing for two-way in intermediate we're using
black as common and then we've got brown and brown in our one one from the twin and CPC and one from
the three core and we've got a blue with a brown sleeving and a grey with a brown sleeving coming
out the other connection within the two-way switch the intermediate switch the one in the
middle now has a slightly different configuration the switch itself has four termination points and
the general rule with intermediate switches is a set from a three core will go in the top set from
the three core going to the bottom wouldn't matter which way around they go as long as the set goes
in the top and the second the bottom occasionally manufacturers do across the side and all the ones
are using my workshop will have a set coming in the top and a set going at the bottom so from the
three core we can see we have a brown and grey from one of the three core and cpc's going into
the top and the grey again is identified with brown sleeving and in the bottom from the other
three core we'll use the brown and grey with the brown sleeving identified again these brown and
grey conductors connected in the intermediate switch are called strappers the common is not
physically connected into a termination within the switch itself it is actually joined together in
other words the black common from the top switch and the black common from the bottom switch are
connected together and left in the back of the box of the intermediate switch I've shown a red
through crimp for the connection here but it also could have been a maintenance-free connector to
join those two conductors together and the 3 core coming out the intermediate switch down
to the final two way switch has the standard configuration for connecting in our case we're
using black is common and we've got brown and grey with brown sleeving connected in L1 and L2
remembering again it wouldn't have mattered if brown was in L2 and grey was in L1 the drawing
shows them the other way around so this would give us two-way and intermediate switching of a
lighting point so in other words there is three positions in which we can turn the light on and
off from however a stated previously you could have had as many intermediate switches connected
as shown here in this circuit as you'd like to have vastly greater control over the light so
we could have had 10 switches controlling the one light hope this has been some help