multifunction box failure

[bitupset]

These multifunction boxes keep burning out on me...any idea what component would be burning out so easily?? any idea where i could get a skematic to make my own??? Thanks in advance for any advice anyone can offer...

2011-10-31_21-37-33_892sm.jpg

[dirknerkle]

Looks like there's a little black on the board along the bottom left two circuits. None of the SCRs on the board have blown (they sometimes just explode) so I'd look at possibly the cable itself for those two strings of lights.

ON second thought, do you get any voltage at those outputs? I'll guess it's around 50v. If there's voltage at the points but not in the lights, then something has blown in the wire. If you don't get voltage there, it could be the SCR for that channel.

[bitupset]

The little black was me, when i was testing for voltage there, those are the 2 that come from the wall. They report 119v...but nothing coming off the other 5. left to right 1,2,3,4,5,6,7. 1 and 2 being from the wall. 3, 4, 5, 6, are the 4 different strings and 7 i guess is the negative.....7 with 3, 4, 5, or 6 i get no volts....

Forgive for being a noob, but what are SCR's?

The lights are in this ball, i'd hate to have to re-do the whole thing, takes like a week and i already did re-do once when the first muti's stopped working. this one worked all last christmas, and then this year i turned on and no multifunction blinking, it was just on solid....then the next time i turned it on, nothing, then like after 3 minutes the lights came on solid for a minute or so and then went dark....hasnt lit up since.....what in the cable would get messed up?
2010-10-15_19-10-39_259.jpg

[damo1271]

If this is anything like the ones I have been working with the two wires on the left are the mains input. The next 4 wires drive each 'channel' in the string and the last wire (right) is the common for the 4 strings.
I have attached a document that will give you a basic idea of how the circuit works, but it is not exactly for the board you have. (Unfortunately I can't credit / acknowledge the author of the document as I dont know where it came from.)

[bitupset]

the cap on my board is 16v. can i just shoot 16v to each of the 4 lines and bypass the multifunction box altogether?

[budude]

the cap on my board is 16v. can i just shoot 16v to each of the 4 lines and bypass the multifunction box altogether?

That is the MAXIMUM rating for the cap so it's unlikely there was ever 16v there - probably somewhere between 5-9 or so...Can you provide the part numbers of the SCRs (if any)?

[bitupset]

the 4 black parts, that control each line say H XL 1225.

[TimW]

its likely that the controller is outputing DC (of sorts)- Are you measuring the ouputs on AC setting perhaps?

[TimW]

Damo, please, please tell us the strings you're playing with are not like that circuit! And please noone else build it!

(christmas isn't worth pumping 270V round led strings on your house or garden, seriously!)

You are right, the basic cct is similar, kind of. But most of the multifunction controllers have specialist chips that provide 8 different patterns and enable the lights to dim as well as switch on and off. They use scr/thyristors (like XL1225) to control the lights, using pwm like most of our controllers.

No (legal) lights should take 240v, rectify it and pump it out to light strings....

Tim

If this is anything like the ones I have been working with the two wires on the left are the mains input. The next 4 wires drive each 'channel' in the string and the last wire (right) is the common for the 4 strings.
I have attached a document that will give you a basic idea of how the circuit works, but it is not exactly for the board you have. (Unfortunately I can't credit / acknowledge the author of the document as I dont know where it came from.)

[bitupset]

its likely that the controller is outputing DC (of sorts)- Are you measuring the ouputs on AC setting perhaps?

i always try both....no juice.