LED Rope light power lead

[Rick Graves]

Hi All,
Some advice please ladies and gentlemen.
I recently purchased a 42M LED Rope light. It works fine with the cable that is hard wired. However when I make a cut in the correct area and follow the instructions to the letter adding the supplied power leads there is an audible pop, a puff of smoke and my fuse trips.

I have now taken one of the leads apart and it doesn't look right to me at the transformer, what do you think?
Thank you for your help.
Rick

 

[SparkyChick]

Where does the audible pop and puff of smoke come from?

Can you provide a little more information about the product? Maybe a couple more photos, particularly of where the puff of smoke comes from.

And no, that doesn't look good.

 

[Rick Graves]

Where does the audible pop and puff of smoke come from?

Can you provide a little more information about the product? Maybe a couple more photos, particularly of where the puff of smoke comes from.

Hi, thank you for your reply.
The smoke and pop come from the transformer driver which I have now stripped apart. The lead is around 6ft long with a fitted plug and 13 amp fuse.

 

[mache]

Hi All,
Some advice please ladies and gentlemen.
I recently purchased a 42M LED Rope light. It works fine with the cable that is hard wired. However when I make a cut in the correct area and follow the instructions to the letter adding the supplied power leads there is an audible pop, a puff of smoke and my fuse trips.

I have now taken one of the leads apart and it doesn't look right to me at the transformer, what do you think?
Thank you for your help.
RickView attachment 36682

Four possible reasons come to mind initially.
1. The transformer was faulty at time of original supply. (was it working before shortening the power cable.)
2. Incorrect Instruction Manual Details
3. Unfortunate surge event occurring at the exact moment of switch on.
4. Error in following the instructions.

Not being unkind but the last one being most likely unless you are experienced in electrical equipment and wiring.

 

[SparkyChick]

I've not got any experience of this stuff, I just figured I'd post for a bit more info for when the guys get on, save them the trouble.

That transformer doesn't look good at all. Was it connected to the reel when it was delivered or did you have to connect it yourself?

The exposed copper on the blue and brown wires on the transformer... did you do that opening it? What's the other side of the transformer looking like. Either the black staining is from the plastic that obviously encased it, or it's damage from a fault.

Is this the only power lead you've tried? I think if it had been me, I might have just sent it back when it first went pop.

 

[DPG]

I suspect a short was caused in the cutting process and the (dodgy looking cheap Chinese) transformer couldn't handle it? Could you clarify what was cut and where. And a photo of this bit would be good.

 

[Rick Graves]

Four possible reasons come to mind initially.
1. The transformer was faulty at time of original supply. (was it working before shortening the power cable.)
2. Incorrect Instruction Manual Details
3. Unfortunate surge event occurring at the exact moment of switch on.
4. Error in following the instructions.

Not being unkind but the last one being most likely unless you are experienced in electrical equipment and wiring.

Hi, the power cable has not been shortened. 42M of rope light is supplied with 3 additional power leads which can be connected to unused rope light which can be cut at about every 1.8 metres where it is marked with a cut indicator. One of the leads worked fine but the others just trip the fuse

 

[Rick Graves]

I suspect a short was caused in the cutting process and the (dodgy looking cheap Chinese) transformer couldn't handle it? Could you clarify what was cut and where. And a photo of this bit would be good.

The LED rope light was cut at the correct cut mark. Supplied power cable fitted and bang. Like you I suspect Chinese transformer and wonder if it was wired wrong at the factory, that's why I stripped it apart.

 

[DPG]

Check for fine strands of wire which may have touched where it has been cut.

 

[Rick Graves]

Check for fine strands of wire which may have touched where it has been cut.

 

[DPG]

Ta for photos. Could you measure continuity between the two conductors of the rope light (without the transformer connected).

 

[Rick Graves]

Ta for photos. Could you measure continuity between the two conductors of the rope light (without the transformer connected).

Done, yes there is continuity

 

[DPG]

Done, yes there is continuity

I suspect that is your problem then. Although I've just remembered it's LED rope light - do the continuity check with meter leads swapped over. See if you get 0 ohms both ways.

 

[Rick Graves]

I've not got any experience of this stuff, I just figured I'd post for a bit more info for when the guys get on, save them the trouble.

That transformer doesn't look good at all. Was it connected to the reel when it was delivered or did you have to connect it yourself?

The exposed copper on the blue and brown wires on the transformer... did you do that opening it? What's the other side of the transformer looking like. Either the black staining is from the plastic that obviously encased it, or it's damage from a fault.

Is this the only power lead you've tried? I think if it had been me, I might have just sent it back when it first went pop.

The transormer was connected to the lead and sealed in a black rubber casing. I exposed the wires when opening so that I could post on here, I was wondering if it had all been soldered up wrong blue to brown, brown to blue. I tried 2 other leads which also made a bang. One that did work correctly is currently powering 20+ metres of rope light wrapped around one of my trees. Here is a pic of lead as it came:

 

[rsgaz]

I don't get why the "transformer" says DC out, but the lights say 240v 50-60Hz.

It can't be a transformer, it's either a rectifier or just a single large diode IMHO, which has exploded due to too much current.