joining 2 lengths of led christmas lights together

[sjroberts1]

hi, not sure if i can do this so will ask you helpful lot

i have a set of 400 and a set of 200 blue and white led christmas lights from BandQ. they both are identical in every way, transformers wire configuration etc the only difference is the number of bulbs.
i turn both the lights on using an extension lead so they turn on at exactly the same time but they never run in sync for long- they start all flashing and changing colour at the same time but within a minute they are doing totally different timings.

my question is

can i cut the plug off one of the sets and then join/solder the string of lights on to the end of the other set?
if so what would be the best way to do this to keep it weatherproof?

cheers

steve

 

[ricicle]

Probably not. The controller circuitry will possibly only be sized for the set amount of LEDs. (Unless it is a specific set which allows expansion but these come with the provision to do so.)

P.s You're a bit late aren't you ?

 

[Taylortwocities]

Impossible to say,
the driver, etc may only be sized to be big enough for one set of lights.
The lights may be wired in parallel, or they may be wired in series.
There may be several wires coming out of the control box (ie the one that controls the flashing).

My be worth going back to the maker and asking them (Ganching China?) but dont worry, you've got 11½ months to do the research.

 

[Gavin77]

The short answer is no.

The longer answer is no because:-
1. You would be putting a much higher load on the transformer than it was designed for, so chances are it would fail rather quickly.

2. If you determined that the transformer was capable of running the extra load, then you need to figure out how to wire them. Im not how these LED chains are wired up, but LED's are current controlled devices, therefore you can't just 'parallel them up' unless each led has a build in resistor. I would assume the current control is within the control box.

 

[dhutch]

Assuming they are the same lights i have form BnQ (and proberly the case even if they are not) they will be wired in paired batches. Each batch contains 20 leds in series, is paired with another batch of 20 (giving ten of each colour, about 3ft) and then placed in parrallel with further batches to make up the set.

Ie of the three wires leaving the transformer;
- One wire will go the first bulb and daisy chain ever other for 20lights to make that batch.
- One wire will go to the second bulb and daisy chain ever other to the end to make that batch.
- And the third 'common' or 'ground' wire will run past all the lights in that batch and link to the far side of the end two bulbs.

On top of that, a 'feed' wire from the first bulb of each of the two batches goes on with the common to the end of that batch, given three wires, for the next batch in the set you attach to.

If you look you can quite clearly see that for most of the set there are five wires, but every 3ft or so it necks down to three before going out again.

I bought three 400 led sets (full price, but 3for2) which i used this year but also six 120 light sets when they where on clearance (75% off) which have visually diffrent but otherwise very simular controlers. Infact the120 set actualy has a fractionally more powerfull spec of control. Something like 0.8 amps rather than 0.7 a (figuares are just from memory not nessarlly acurate) and hence it was my plan to join the 6ix 120 lights sets into two 360light sets sometime between now and next year which i dont expect will cause an issue. Joining 600 (400+200) into one might be pushing it and kill the control box, although at the same time, I wouldnt be supprised if it was fine, but clearly going to loose any warrenty that may or maynot currently be inplace.

I also had a little bugger rip one of the 400 sets off front wall, which i sucessfully rejoined and put back up, intill they did it again last night (coming down friday anyway) so that sets now in half a dosen 4-6ft lenghts! Might mark out complete 'batches' and salvage what i can of that.

Few posts on this thread also:
//www.diynot.com/forums/electrics/fcking-xmas-tree-lights.303344/page-2


Daniel

 

[dhutch]

P.s You're a bit late aren't you ?

One day of christmas left. Down on the evening of the 6th.

 

[ban-all-sheds]

i turn both the lights on using an extension lead so they turn on at exactly the same time but they never run in sync for long- they start all flashing and changing colour at the same time but within a minute they are doing totally different timings.

How terrible.

That must make them look absolutely awful, instead of the tasteful effect you'd have if they flashed and changed colour in unison.

 

[ban-all-sheds]

I also had a little b*****r rip one of the 400 sets off front wall,

A taste vigilante!

Excellent!

 

[dhutch]

That must make them look absolutely awful, instead of the tasteful effect you'd have if they flashed and changed colour in unison.

A taste vigilante! Excellent!

Got out of bed on the grumpy side today b-a-s?

I have to say i am a christmas light fan and do let good taste slip a little in so much as I do make sure there are good number of lights up. However do try and retain an amount of taste in there arrangment, which this year consisted of a string of lights around the boundry of the road and the front and a rear gardens (we're on the corner) and a third set inside outlighing the ground floor windows. With further 'inluminated bourble' type lights in the two dwarf trees in the front garden. No set peices, noding reindeer, or inflatable santas.

And crutially in my opinion, all lights set to static, no flashing at all, which also resolves the issues the OP has hiehglighted, although creates the issue that turning them off anf back on requires each set cycaling round to static, which i solved by leaving them all on 24/7 being greatfull of them being led and only about 8w per string.


Daniel

 

[sjroberts1]

i thought as i took them down that perhaps i could join them before they go into the attic for the next 11 months, didnt think about leaving them on all day seeing as they are led's and use very little power just dont know if the neighbours would appreciate that!

so i might try and join them just not sure if it'll work, otherwise it'll be order an extra long set or connectibles for next year, be a shame tho as i do like these ones ( when they are in sync!)

i would need an idiots guide to follow if anybody has time to really spell it out simply

many thanks

steve

 

[dhutch]

...didnt think about leaving them on all day seeing as they are led's and use very little power just dont know if the neighbours would appreciate that!

Hard to know isnt it, during the day you cant really see there on, over night they dont add much light ontop of the streetlighting. Annoying if flashing, but maybe not if static. Then again, maybe thats why they where ripped down. Although both occasions where a saturday evening and we are the corning leading into a large pair of cul-de-sacs so prehaps now.

I think my explanation is fairly clear, i could draw a diagram, but might not get around it this week!


Daniel

 

[Trazor]

How terrible.

That must make them look absolutely awful, instead of the tasteful effect you'd have if they flashed and changed colour in unison.