okay then Joe we're back in the electoral workshop and we're going to look today at
some popular early misconceptions of our learners so they're going to be with us for the first two
or three weeks and we start getting things slightly confused from the start it doesn't
help us moving forward and we're going to be looking predominantly in this video at
the batten lamp holder talk me through some of those little misconceptions Joe so perhaps one
of the first things that we might get a little bit confused about when we start looking at
batten lamp holders is the fact that we've got two white wires here okay now that might be a little
bit unusual to a learner coming into this because so far we've been speaking about brown and blue
conductors we've talked about line and neutral at no point have we spoken about white conductors so
the first thing to clear up really is why are there two white conductors in here Gaz it goes
back to a video that we shot when we talked about lamps didn't it well we talked about different
varieties of lamps so we've got a lamp here and again as it's a new video what is it not just it's
definitely not a bulb it's a lamp it's an electric lamp and we'll get to that in the classroom or in
the video that we did on lamps and we've got the bayonet cap lamp holder on the end okay and we
also look in that video Edison screw but we're going to concentrate on the bayonet cap one here
and we talked and we in a previous video presentation that the two contacts on the top
which one's line and which one's neutral Joe we have no idea it doesn't matter okay and when you
think about that when you're in your own home and you're changing an electric lamp into your
light fitting you don't think i must put it in the right way round you just put it in don't you
and it works either way that's because this kind of lamp has no polarity in other words it doesn't
matter which one of those two terminals you connect up to the line and which one you connect
up to the neutral okay so with that in mind then so it doesn't matter which line and neutral we're
going to say in other videos and this one as well we'll just drop it in again it has
no polarity so when we drop over to your batten lamp holder yep one here got part of it you've
got a completed one there is that why they're both white then uh yes that is basically the reason now
what we're not saying here is it doesn't matter where your line and neutral conductors going
to the base but once these two wires have left the base picking up the line
and the neutral it doesn't matter where they go into a batten lamp holder type
lamp holder so that's what we're looking at there so that's the reason that we don't have
a brown and a blue conductor inside our batten lamp holder in this make yes so in this make so
we grab a different mate so again we come to this one yep okay we've got a ah now
so i believe we've still got a batten lamp holder so we've still got a bayonet cap lamp there so it
doesn't uh matter about the polarity of the lamp however this manufacturer has chosen to go with
brown and blue okay so again when our learners get them out they're thinking oh right i've got a blue
one i've got a brown one again for my learners and learners out there perhaps are watching
still check that the person before you hasn't taken these out at some point and actually
swapped them around so even though the lamp holder has no polarity we'd expect the blue
conductor to be connected in the block of three labeled neutral and then the brown conductor in
the block of two labeled with an L and we will say at this college that is actually switching line
yeah not just an l center terminal what's that called Joe that's generally called the
loop terminal uh i always think of it as the permanent line connection yeah so that's where
your your permanent line conductors go and that middle terminal will always be live as long as
the circuit is on that will always be live which is again another good reason why we must perform
safe isolation which we've done a little video on yeah to make sure you kind of switch it off at the
lamp because that only turns off the uh L terminal yeah not the loop terminal so there's still live
parts in there so while we're doing popular misconceptions early on for our learners um
that's a block of three let's use that one as the example of which our permanent line conductor can
come in and go out and then it's usually one down to a switch as well so it could be populated with
three conductors yep all what colour oh they'll all be brown okay and our owners will come to us
and they'll look at the drawing they've got and they'll see how they go in particularly into a
hole so there's three holes so as we look here so there's a brass uh block of three with three holes
Joe and it's vitally important isn't it joe that they get them in the right order absolutely not
that's one of the common questions that we get asked during lessons is uh i've got these three
terminals in the middle block effectively which one do i need to put my line conductors into
well if you're putting it in there it's going to be permanently lined whichever hole you connect it
into so normally the right answer is whatever looks the neatest good that's the way forward
and we're laying and dressing cables out uh we'll just pick up another thing or two as we go through
um that these blocks of three or blocks of two are separated by insulators from each other so
they can't touch each other and the nominal value of voltage for these accessories is 250 and we'll
talk in the classroom about how the voltage can rise and fall from the nominal value of 230 so
we'll hold that one back for the classroom we like to leave little bits out of our video don't we
yeah so we can just blend it in as we go along so i learned to get something like the live the live
show but when we're looking at the flexible cord coming to our ceiling rose and pendant as it's a
flexible cord Joe they're always going to be blue they're always going to be brown it's only in
the back lamp holders yeah do you agree well we can have a combination of either the white yeah
or the identifiers sometimes get the whites yeah absolutely while we're talking about pendants
another sort of just little point there again our learners often with the batten lamp holder
go to lots of trouble of wiring these flexible conductors here going out to the lampholder itself
through the cable retention through the cord grip and making sure that that's in there now when
you're installing a pendant type light fitting that is really important absolutely because
you don't want the connections to be taking the weight of the light fitting you want the
actual plastic plate to be taking the weight of that yup yeah but in a batten lamp holder okay we
don't need to use those cord grips we don't need to use that cable strain relief because actually
the whole light fitting just screws onto the base okay like so so there's no stress on those two
conductors behind it absolutely wearing obviously the ceiling rose and pendant there's a chance that
we can have something heavy pulling against those so we use the the cord grips available
in the actual rows itself so i think that Joe we've covered quite quickly some of those popular
misconceptions yeah that we could have two white conductors we know they can be white because there
is no polarity on a bayonet cap lamp um we know that our terminals does it matter which of the
three we choose say for a line conductor no so just to clarify that we've got three blocks of
terminals we've got the one marked L yep the one marked loop and one marked N or neutral
and within those three blocks two of the term two of the blocks have three holes in them and those
three holes it doesn't make a difference which line conductor goes where in the center block
and it doesn't really matter which of the two holes the neutral conductors go into we normally
keep the flexes on the very outer terminals don't we that's that's really good practice so
we would suggest that that's the way forward but apart from that it doesn't actually matter which
one of the holes it goes into as long as it's the right conductor they're made of brass yes
not copper they're made of brass okay a non-dissimilar metal to copper so when
we terminate the two there's no electrolytic corrosion between the two so we'll talk about
that as well in the classroom so Joe i think is a little kickoff for those first four or five weeks
that our learners are underway with i think we've covered some of those popular misconceptions about
the batten lamp holder shall we end it i think we will we hope this video has been some help