Problem with DIY light fitting

Alderbank

Will not work at all if any bulb is missing.

One LED bulb and three empty sockets = lights up fine.

Oh dear. You have a problem, and not just with the lights

grumbler

TuppenceWorth said:

Alderbank said:

TuppenceWorth said:

Thanks all.
I will  need to get more filament bulbs to answer the question about brightness.

Another observation after I switched bulbs around:
It's actually a series of four lights. It will work as long as any of the four lights has a non-LED bulb. Will not work at all if any bulb is missing.

With four LED's it comes on at low brightness for about 3 seconds before flashing haphazardly...

That solves it then. Defo all in series.
Impedance of four LED circuits in series too high for them to get enough current to work properly. Filament bulb has 10% the impedance of LED circuit. Just enough current for LEDs to limp along.

OP, I don't think you need any more filament bulbs. Can you post a picture of the wiring?

One LED bulb and three empty sockets = lights up fine.

Two LED bulbs and two empty sockets = haphazard flashing and then off.

GrumpyDil said:

It definately sounds like these have been wired in series. 

No, it doesn't 

dil1976

Sounds like you have lost a neutral somewhere

TuppenceWorth

Alderbank said:

Will not work at all if any bulb is missing.

One LED bulb and three empty sockets = lights up fine.

Oh dear. You have a problem, and not just with the lights

Sorry my bad.. 

Should be doesn't work if the filament bulb missing

TuppenceWorth

dil1976 said:

Sounds like you have lost a neutral somewhere

That's great..
Will check the neutrals and if that fails, will be time to get a professional to have a look..

chris_n

Are these low voltage lamps? I suspect you have a transformer that doesn't cope if the current is too low. I have seen this before, sometimes if the transformer is inaccessible I have left one filament lamp in and replaced the others with LED. It is better to get an LED compatible transformer / power supply.

TuppenceWorth

They are just bog standard wall lights..

Checked the wiring this morning and all seemed secure.

Situation now a little different:

One LED = dim
Two LED = even more dim
Three LED = even more dim 
Four LED = no light at all

One filament bulb and all work fine.

Thanks for all the input.
At least now  I know what might be the issue. Will ask the electrician to give his view on the transformer and to check the neutrals.

Thank you 🙂

chris_n

^That is why the authorities don't like diy electrics. There should be no copper showing on the earth, you have cut some of the strands on the earth and there is a strand sticking out out of the live. 
If they are mains voltage lights there will be no transformer. 

grumbler

chris_n said:

There should be no copper showing on the earth

If it's really a requirement, then it's a stupid one, at least in this case where the earth wire is connected directly to the metal casing.
And, quite possible, it's not DIY as it looks like these wires came with the lamp. I don't understand what TuppenceWorth wanted to show with this meaningless photo.

Alderbank

OP, you simply refer to bulbs as LED or filament but there are many sub variations of each.
Exactly what style is each bulb you have? GU10? MR16? SES (small Edison screw)?
What other data is written on each bulb (voltage, current (mA), lumens (lm), etc?

I think some of us (including me) have made assumptions which are not correct.