Completely baffled by a 3 lamp chandelier blowing fuses

[astvillain]

Hello

Right I cannot get my head around this one.
I have a 3 lamp chandelier - I have done a drawing of the connections below.

It has been placed on the 1st floor 5amp lighting main in the existing ceiling rosette (which previously had a 80 watt filament bulb.)

I bought a LED dimmer switch (with an automatic overload cut out).
I bought 3x 3W (40W equivalent) dimmable LEDs.

I screwed the first bulb in, turns on no issues.
I screwed the second in and the dimmer switch cuts out.

I repeat this a few times, resetting the switch in between, I re-check the wiring to the lamp holders, all fine visually (i.e. the diagram I drew is accurate).

I then override the automatic cut out, screw in all 3 bulbs, turn it on and it blows the dimmer switch up!

I then swap broken dimmer for a normal switch and once again with a single bulb in it works fine. It works fine in each individual lamp holder with a single bulb - i.e. there isn't a problem with one of the lamp holders vs another.

But then when I screwed in two bulbs and flipped the switch it blew my main 5amp fuse in the fuse box.

So I am now baffled. Presumably it is overloading the circuit. But how can 3 low wattage LED bulbs do that?

If it was a loose connection then surely it would blow with just one bulb in? But it doesn't.

I am really puzzled?

Help much appreciated.

Thanks

 

[Strima]

Sounds like dodgy lamp holders shorting out when you screw a lamp in. Best optio would be to get a local electrician in to carry out a few tests.

Not made in China by any chance?

 

[astvillain]

I have just screwed in 3x 25W filament lamps and it works fine... its only blowing the breaker when I use the 'dimmable LED' bulbs.

Could the bulbs be dud somehow? Surely you couldn't get an LED bulb that wrong it would overload a circuit... and these bulbs are still intact and working fine individually?!

 

[Gavin John Hyde]

@astvillain Where did you buy this light fitting from? Its fine until you put the bulbs in so that tells you its either dodgy bulbs or the holders... i would edge towards the holders myself.
Out of interest have you been putting the bulbs in to the holders in the same order as you could possibly identify the offending bulb holder but you could run out of bulbs or damage your breakers if you keep tripping it. If its the say the middle one or third one that keeps causing the issue then maybe try it with 1 bulb in no 2 or no3 on its own etc to compare outcome

 

[Strima]

Try some different LEDs

 

[astvillain]

Holders appear fine, as like I say, each works individually with the LED bulb or work all together with normal 25W bulbs... they only blow the breaker if you use 3 LED bulbs...

The LED bulbs were from amazon. The lamp holders were from ebay, but seem pretty well made visually.

 

[Gavin John Hyde]

eBay = could be made from anything and made anywhere by anybody. Never trust a label on something from eBay.
Likewise with Amazon i only by if its sold by or fulfilled by amazon as too many charlatans are selling on amazon these days trying to fleece you of your hard earned cash.

 

[astvillain]

I suppose I was mainly wondering if the problem could be because the lamps are wired in parallel instead of series?

Thoughts

 

[dmxtothemax]

cheaply made lamp socket in combination with a cheap lamp base,
it's just asking for trouble.
Have a close look at the lamps bases ie the incandesant that works
and compare its base construction with the LED lamps that don't work.
most likely something is causing a short circuit when you put the lamp in.
The only way out is to replace one or the other,
The lamps would be the easiest to replace.

 

[marconi]

Are you using a dimmer designed to dim LED lamps? What do the instructions for the LED lamps and the dimmer say? Not all dimmer technologies are suited to LED lamps or give complete and satisfactory control in light level.

For example see this guide for varilight products:

https://www.tlc-direct.co.uk/Technical/DataSheets/Systems/Dimmer_Selector_2016.pdf

You need the right dimmer technology otherwise the lamps or the dimmer or both will fail, be noisy or have shortened lives.

 

[The Ghost]

The first thing to do is test the lighting fixture for any shorts. This will require equipment you may not have. Also look on ESF.orf they have a list of lamps withdrawn due to safety issues you can check if you have bought such an item on there. Is your lighting fixture CE marked, although as stated above this may not be worth the paper it's printed on. It may be that as yuo changed the light fitting you made a mistake on the existing wiring and left a loose cable or omitted a cable. All of which points toward getting an electrician to assist you in the matter.

 

[Toneyz]

I think it could be the LED lamps or one of them as seems to work ok with other "normal 25watt" lamps. Could be one of them has a L-N sort in the electronics, just a thought.

 

[Octopus]

Are all the other lights on the circuit switched on or off?