i'll have mornings like this Marcus you've invited me out onto site what am i here to see so the
customers had a recent consumer unit change Gaz one of them lovely Hager boards you've seen at the
elex show you loved what those ones were the type 2 SPD and the type A RCDs oh fantastic so we're
gonna have a look at that consumer unit but you've also said to me on the way over there is something
else you want to bring up in this presentation yes i want to show you in regards to testing the
RCDs and maybe some issues you might have on site with testing the Hager 61008 RCDs okay so there's
something in there that all electricians need to be made aware of when testing those A type RCCB
100% and we can see how we can get around that with the Megger MFT that have okay so first of all
let's have a look at the consumer unit yeah and then let's look at those issues that we could have
and how to solve them when testing those RCCB's it's wonderful from my point of view Marcus to
see one of these fitted we absolutely loved them at the elex show me and Joe shot a video on these
can you show us some of the key points again with inside the consumer unit yeah of course Gaz
just be aware when i lift up the lid the electric contractor is still on site and in the process of
labeling up the consumer unit i've got to see him putting some LED down lights throughout the ground
floor of the dwelling okay so as you see we've got stickers like the SPD stickers still to go in
we've got obviously all of our circuits individually labeled just remind us what
type of SPD is it so we've got a type 2 surge protective device and that is in parallel with
the main switch the RCCB's are what type so we've got two type A RCCB's rated at 100 amps
and 30 milliamps for additional protection that's wonderful let's cut away and have a look at the
testing now because you said there were some issues when testing those RCCB's yes there was
so mark as all loads are off and we're plugged into one of the socket outlets
can you set up the Megger MFT in order to carry out the RCD test for me please yeah so we're
going to first of all set it to half times our delta m okay and set it to 30 milliamps as it's
offering additional protection okay now at the minute it's actually set
to the ac waveform for an AC RCD we're actually going to switch that now to a type A RCD okay
so scrolling through yep so now you can see that the waveforms have changed okay we've
picked that up in a previous video presentation that you shot with really yeah yeah okay so what
do we expect to happen now when we press the test button it's not going to trip let's see that then
just what we want okay confirm the circuit still on we're going to rotate it around to now 180
degrees we are yeah both sides of the cycle again shouldn't trip okay so we're all good
so far yeah okay now we're going to test out one times our delta m
we've gone back to zero degrees yeah we're still on a time we are
103 milliseconds wow i've never seen numbers that big before no still acceptable however
still on the high side okay but yeah it's well within the 300 except i think that's probably
just going to be a psychological change in thinking yeah that we're not going to see
very very small numbers we're now going to see maybe higher numbers but than these A type RCDs
yeah okay so it's well under the 300 milliseconds acceptable you're changing the angle again yeah
again 105 milliseconds right okay that's again a large number but well within the
300 milliseconds acceptable this is where you had a few issues now i think you'll find yeah so
originally hopefully the value will be the same however when we tested at
five times our delta rent so we would put 150 milliamps into the RCD okay
it actually tripped at exactly 40.0 milliseconds wow right at the maximum allowance yeah okay
let's see what we get this time this RCD has been obviously warmed up a few times [Music]
so even though it has come slightly down it is still right at the point where you're
thinking that's still acceptable because it's under 40 milliseconds yes it is okay at 37.7
milliseconds so we're going to go again we're going to change the angle over again
so we go once again the other side of the cycle [Music] and that's that's slightly less
at 32.4 milliseconds it's still what you're not conventionally used to see in though is it i'm
used to seeing nine yeah eight milliseconds so what we did was we went away didn't we
Marcus we did yeah and we had a look at the literature online from Hager okay then
Marcus so now we can see the updated literature online from Hager's suggesting that we now need
to test this actually not a 150 milliamps what we're got to test it out yeah so now
according to the document it's 250 milliamps now BSEN6100a allows manufacturers to choose their
test parameters and these type a RCDs by Hagar actually rated at 250 milliamps as opposed to
150 milliamps for 40 milliseconds disconnection time as we've just got it to disconnect within
the maximums as we've just tested i've cleared it with mega and they say that's totally acceptable
what we've just done carried out the test as we normally would yeah it's come within
the parameters required under 340 milliseconds we're probably not going to do anything else
we've found that industry's gone out done the testing at five times and it's gone over
a lot of failures yeah and they're sending the products back they are yeah when there's
not actually a need to we just need to work out how we can pass 250 milliamps through the RCD
do you know how to do that with the Megger MFT yes i do yeah okay let's set it up to pass
actually now 250 rather than threat so on this Megger MFT we're going to go to the variable
setting on the RCD and what this allows us to do it allows us to choose what milliamps we're
actually putting through the RCD okay so i've got it set to 50 milliamps how did you do that
can you just yeah yeah so the arrows there when you see these two up and down arrows
there's the corresponding arrows on the test buttons this allows you to increase the value
oh right okay and decrease the value so we're going to set that to 50 but i thought we're going
to pass 250 milliamps to it we're going to do 50 milliamps at times five okay that makes sense
again recommended by Hagar on there so yeah we've got the five times here five times 50 is the 250
million and that's what's recommended in order to test it when we're doing the five times test
for this type of Hager RCD it is yes let's do the test and see what we get this time
oh that's that's a little bit more like it 19.3 so that's now doing what the
manufacturers require us to do which is to pass the 250 milliamps through the RCD
rather than the conventional 150. on both sides of the cycle again
okay and we've got to get 19.3 so what we're really saying is that this is a full back test if
we didn't work on a conventional three test that we can up it to five times 50 being the 250 yeah
because it's not actually a recognized test practice as of yet in in the united kingdom okay
thank you so much let's clarify what's going on today we've tested our RCCB from Hager yeah type
a and we've tested a half one and five and we've found all those readings are acceptable they were
yeah however people in industry have been testing these and even yourself the first time around
you got exactly 40 milliseconds five times which obviously flagged this up that we've now saying
after looking at the website that Hager produced with additional information about testing their
RCDs is that we should go where it doesn't pass a five-time test at 150 milliamps we're going
to pass what for it 250 milliamps and that's 50 milliamps times 5 like you've seen earlier in
the video okay and then we're confirming through that one that it will disconnect within the 40
milliseconds yeah is there anything in BS7671 to support this yes so the 18th edition is actually
allowed for this under regulation 643.8 okay and that states that the effectiveness of the RCD is
deemed to be verified when it's tested at equal to or higher than five times its rated residual
current okay so they're a little bit supporting that's good so Hager have put a document out to
support it they have yeah we've now cleared it up that people are out there in industry fitting
the boards that gas loves jojo's and you love but however we're having issues at the five times test
yeah hopefully this video presentation has cleared up how we can overcome that by testing it at 250
and it's obviously always important now to just check with the manufacturers again depending on
the manufacturer it might be slightly different yeah look at the instructions yeah yeah okay
so Marcus yeah what we're going to say no i know here we go we hope this video has been some help