Jump to content

DONT STAY LURKING AS A GUEST,

JOIN TEF AND BENEFIT FROM MEMBERSHIP:

CLICK HERE TO JOIN.
Mastbruch

Downlights Tripped

Recommended Posts

Mastbruch

Just looking for a bit of help. Just finished fitting some Downlights and they have tripped the downstairs, the wiring all look spot on yet when I tried again only 3 of the 8 lights worked.  I have a tester should I test continuity from the switch or would an IR be appropriate.

 

Thanks.

Share this post


Link to post
Share on other sites
Andy™

you should have already tested continuity & IR before it was energised. my guess is you failed to IR and not detected a fault, once powered up its tripped the breaker but blown fault apart which is why it now doesnt trip but only some work

 

id be looking for a fault at the last light that works or the first light that doesnt work

Share this post


Link to post
Share on other sites
ProDave

Start by looking for the wiring fault at either the last of the 3 working ones, or the first of the remaining non working ones.

 

EDIT: Beaten to it by Andy

Edited by ProDave

Share this post


Link to post
Share on other sites
Murdoch

Tripped mcb or rcd?

 

best you go to basics of dead testing

Edited by Murdoch

Share this post


Link to post
Share on other sites
Mastbruch

Thank you

 

RCD Murdoch

 

Really peed off I didnt do the tests before hand Andy, very annoyed with myself.

Share this post


Link to post
Share on other sites
Murdoch
17 minutes ago, Mastbruch said:

Thank you

 

RCD Murdoch

 

Really peed off I didnt do the tests before hand Andy, very annoyed with myself.

 

What do you mean peed off .... the bang test is NEVER recommended.

 

no sympathy

 

Share this post


Link to post
Share on other sites
Tony S

Do you have the required test equipment? Your previously started threads would suggest you don’t.

Share this post


Link to post
Share on other sites
Mastbruch
2 minutes ago, Tony S said:

Do you have the required test equipment? Your previously started threads would suggest you don’t.

 

Yes Tony I have Kewtech MFT. I wouldnt of said I wished I would've tested them before if I didnt have a tester.

7 minutes ago, Murdoch said:

 

What do you mean peed off .... the bang test is NEVER recommended.

 

no sympathy

 

 

Agreed Fully

Share this post


Link to post
Share on other sites
Ardet R

At least you have now had good experience of why the dead testing must be completed before powering up, and you will remember this in the future and it will ensure that you test correctly.  In this case there is no major damage so a good lesson learnt.

 

Share this post


Link to post
Share on other sites
Mastbruch
17 minutes ago, Ardet R said:

At least you have now had good experience of why the dead testing must be completed before powering up, and you will remember this in the future and it will ensure that you test correctly.  In this case there is no major damage so a good lesson learnt.

 

 

Defiantly Ardet lesson learned mate.

Share this post


Link to post
Share on other sites
Mastbruch

Just done an IR and that all went through smoothly. Got 2000 L/N 2000 L/E 2000 E/N Then I tested at individual Downlights and I am getting a reading from 0.23 from 4 of them then when pressing the switch 2000 which is fine but the other downlights just getting 2000 when pressing the switch on and off. It so much easier doing it at college yet completely different when you have to do it for real so to speak.

Share this post


Link to post
Share on other sites
Andy™

the real world is completely different to a light & bit cable stuck surface in a little traning room

Share this post


Link to post
Share on other sites
Mastbruch
11 minutes ago, Andy™ said:

the real world is completely different to a light & bit cable stuck surface in a little traning room

Agreed.

 

Any ideas about above Andy? 

Share this post


Link to post
Share on other sites
Andy™

faulty mights maybe? did you zap the electronics at 500v instead of 250?

Share this post


Link to post
Share on other sites
Mastbruch
9 minutes ago, Andy™ said:

faulty mights maybe? did you zap the electronics at 500v instead of 250?

No took all bulbs out and devices unplugged and passed the IR.

 

I really do enjoy fault finding just a pity I am not very good at it as I cant work out why I am only getting readings on 4 of the Downlights. Might have to look at the wiring within the Downlight.

Share this post


Link to post
Share on other sites
Andy™

are they LED or halogen? if halogen then with the lamp removed you should be getting a very high IR reading between all 3 conductors. LED and you will get a very low, L-N and high L-E, N-E.

 

what points are you testing at?

Share this post


Link to post
Share on other sites
Ardet R

You only have three lights that worked so after that third light there is a disconnection.  Because of the disconnection all readings after that in the circuit are high because there is no complete circuit.  Presumably the four lights that show a low reading were the three that had been working and the fourth is the location of the disconnection.

When testing at the downlights with the switch off all readings are high but with the switch ON the readings are low, this would indicate that the fault (between whichever conductors you are testing) is before the light switch, this is slightly odd because you had some working lights which were not tripping and often the fault would be near the disconnection.

However 0.23MΩ is not enough to trip an RCD so the fault may be only partial now.  I would therefore be checking the wiring in the switch to see if there is a damaged core almost touching the back box.

I would also look at light four and reterminate the connections.

Then re test IR to ensure the fault is clear and also at end of circuit do R1+R2 and compare with Rn + R2, they should be similar if the disconnection is cleared.  Remember on IR to test LE, NE, LN and compare readings.

Share this post


Link to post
Share on other sites
Mastbruch

@Andy I tested at the CU for the IR where I tested LE, NE, LN and after this test I then linked the line & earth where I tested first at the socket between the SL/CPC then my R1 and R2 at the last light.

 

@Ardet because they are cheapy LAP Downlights from Screwfix the terminal box was so tight to get the wires in maybe a couple have came loose.

 

Going to check the terminations again when I get home.

Share this post


Link to post
Share on other sites
Ardet R

Ok because i did not know you were doing R1R2 or what units you were giving results in I assumed it was still IR, however the results of the R1R2 show the low readings to be connected lights high ones not connected so still check light four connections, the fault sems to have cleared but check for cable damage or loose connections.

Share this post


Link to post
Share on other sites
Mastbruch

All sorted now cheers for the replies

Share this post


Link to post
Share on other sites
Andy™

so what was the problem?

Share this post


Link to post
Share on other sites
Mastbruch
42 minutes ago, Andy™ said:

so what was the problem?

 

In the thread I said about buying cheap LAP Downlights from SF, We'll after closing inspection the neutrals which were already connected in the connector box's were not terminated properly & had a sleeve over them & it wasn't until I removed the sleeve and bingo.

Share this post


Link to post
Share on other sites
Doc Hudson
3 hours ago, Mastbruch said:

 

In the thread I said about buying cheap LAP Downlights from SF, We'll after closing inspection the neutrals which were already connected in the connector box's were not terminated properly & had a sleeve over them & it wasn't until I removed the sleeve and bingo.

 

But what was the cause of the tripping?

 

Doc H.

Share this post


Link to post
Share on other sites
Andy™
10 hours ago, Mastbruch said:

 

In the thread I said about buying cheap LAP Downlights from SF, We'll after closing inspection the neutrals which were already connected in the connector box's were not terminated properly & had a sleeve over them & it wasn't until I removed the sleeve and bingo.

 

i find it hard to believe that you have 5 out of 8 lights all with the same fault on neutrals not conencted correctly. and as above, a non connected neutral will not cause it to trip, it simply just wont light. so what did you really do?

Share this post


Link to post
Share on other sites
Mastbruch
4 hours ago, Andy™ said:

 

i find it hard to believe that you have 5 out of 8 lights all with the same fault on neutrals not conencted correctly. and as above, a non connected neutral will not cause it to trip, it simply just wont light. so what did you really do?

 

Just basically tightening everything back up and making sure terminations were right. Do you recommend another IR test  

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×

Important Information

Terms of UseWe have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.