2 Channels constantly on

[Christmasaddict]

This may have been covered but I'm not sure if the problem was exactly the same.  I have 3 LE's that I built last year.  After a lot of software problems I finally got my show going last night and it went without a hitch.  Today it started raining and the GFCI tripped and shut off the power.  I have been leaving the LE's on 24/7.  Anyway after about 3 hours it stopped raining enough to reset the GFCI.  Now channels 31 and 32 are on and will not turn off.  I powered everything down and back up and reset all of the LE's.  I can run a sequence but 31 and 32 just remain constantly on.  Thanks for any suggestions.

[kgustafson]

Kinda a well known issue of either the octocoupler or Triac for channel 31 and 32.

Try to isolate the issue to either the octocoupler (easy quick replacement, but more expense) or the Triacs (harder replacement, but less expensive).

First, while grounded (strapped in), swap the small 6 pin chip (the octocoupler) from channel 30 with the one on 31. 
Power back on and test channel 30 and 31.  We know that channel 30s octocoupler works so we are seeing if the problem moves to channel 30 after the swap.  If the problem still persists with channel 31, then most likely your triac is bad.  If channel 30 now is constantly on, then you need to replace your octocoupler (you will have to buy replacements)

If you suspect it is the triac, then you will have to buy new triac chips and you will have to unscrew the bad triac from the heat sink.  You will have to clip off the legs (three of them) from your solder job and pull the remaining bits of leg by desoldering them.  Make sure to clean up all the solder using a desoldering iron or using desolder wick.  solder the new triac back into place for the bad you just desoldered.  Test to make sure this does the trick.

Good luck.

Kurt

[Christmasaddict]

Thank you for your prompt reply.  I have a spare LE that I built this past year that I could use while I try to repair the other one.  This was exactly why I decided to build a spare.  I also have a few spare parts so I may be able to repair the defective unit without too much trouble.  I need to ask a stupid question:  you say this is a "well known issue" for channels 31 and 32.   Are you saying it only affects those 2 channels or could it just have easily affected channels 4 and 5 or any other channels?  Do you know what causes this?  Could it have been the moisture from the rain? 

[RJ]

He only meant that when a triac fails it tends to fail stuck on. If the cords or lights got wet and created a ground then this can make a dead short to ground that would zap a triac.

RJ

[kgustafson]

Yes, thanks for clarifying my comment RJ.

And I have two channels (one each on two controllers) in this 'stuck on' mode myself this year.  I will fix them after the show in January.  I am positive that these are bad triacs that need replacing (but won't know until I replace them).

Kurt

[Christmasaddict]

I followed your advice and replaced the 2 octocouplers with 2 from my new (unused) LE and the problem continued so I am assuming that it is the triacs.  I ended up replacing the defective LE with my spare and ordering triacs and octocouplers from Mouser today.  Hopefully I can have the bad one back up and running in a few days and it will be ready to use as a spare.  Thankfully the spare worked perfectly after programming (it had not even been tested before).  Bad new is it is raining again tonight so I have no show again.  Thanks again for the help.

[Trevor]

  I have an issue with one of my channels as well replaced the Triac with no luck...FORGOT about the octo. Funny things is I have about 30+ of em laying around. SIGH thanks for the help? 

[chrisatpsu]

i have half of an express with channels stuck on, looks like i got some work to do when it all comes down 

[Jeffl]

I learned this year after having to fix one that next year all my controllers are going to be easily accessible just in case. (Most are except for inside the mega tree)  This makes for swapping out a spare easy and "less painful".

[Trevor]

I learned this year after having to fix one that next year all my controllers are going to be easily accessible just in case. (Most are except for inside the mega tree)  This makes for swapping out a spare easy and "less painful".

I hear Ya! I made the mistake last year of trying to "Hide" them in bushes, roof, pine trees, ect ect. Not this year and thank goodness! This year I had to swap out 3 controllers. Still need to get them fixed have one thats giving me some grief.

[tbone321]

i have half of an express with channels stuck on, looks like i got some work to do when it all comes down 

You should be out there fixing it NOW!!!  This will give you practice in case it happens next year before the holiday is over.