Is smoke a good thing when you turn on your SSR?

[scharbon]

I just finished building and enclosing my SSR in a very nice watere proof container. I was very proud of it to say the least. I checked Channels 3 and 4 and everything worked perfectly :D .

Then I went to show it off to someone and hooked up lights to channels 1 and 2. Channel 1 worked great, Channel 2 was really dim, then flickered, then I noticed a flash of light in the SSR enclosure, then I noticed smoke billowing about in the enclosure :shock: :shock: .

I disconnected power, removed the lights, unplugged the CAT 5, opened the container, and saw that R2 was completely fried (started to melt - that is what was glowing). I am assuming I either put the wrong resistor (can't tell anymore - its just a charred blob) in at R2, or I shorted my TRIAC (solder connection between post 1 and 2 of the Triac can't tell since I haven't pulled it out of the enclosure yet) and I sent 120 V into R2.

Since I am assuming a smoking resistor isn't part of the design specification, I am fairly certain I did something wrong (positive in fact). Did I guess right in the paragraph above or is it possibly something else?

Thanks for any input and insight you guys might have. Other than the fact that its not what I was looking for - it looked pretty cool! :lol:

[Wayne J]

WOW... I bet it was cool. LOL but not fun.
Definatley sounds like a short. Just have to open it up and look at the board and check your solder joints and look for any solder bridges.

[Jeff Millard]

I've always been told it was a problem when the "Magic Smoke" was released from something. Can you determine if it was "Magic Smoke?" Post your findings and we'll go from there...
:twisted:
Jeff

[Mudsculpter]

The sound of frying electrics gives me the willies. I've got goosebumps just thinking about it.

[P. Short]

Assuming that you are talking about the resistor between the opto-isolator and the triac, another possibly cause of smoke is a bad connection on the middle pin of the triac.

--

Phil

[scharbon]

I pulled the circuit board out of the case and checked it out. Here is what I saw:

Black charred remains of a resistor (between the opto-isolator and the triac)

No solder connecting Pin 1 and Pin 2 (middle pin) of the TRIAC so I don't think it was that. Either that or it went up in smoke (sounds like a Cheech and Chong thing)

Did notice a burnt area in the trace between the resistor and I believe pin 6 of the opto-isolator for Channel 2. Solder connection on the resistor was pretty much destroyed (very brittle, very dull, very much like the resistor itself!).

So still don't know what happened. I am going to assume a bad soldering job on the TRIAC similar to what Phil posted since I was having trouble making a good clean connection there.

But channels 1, 3, and 4 still work. Its a pitty, that was by far the nicest enclosure I had made (managed to get 5 done today). Looked so nice I thought I was going to take a picutre of it and post it in here. All the wires were aligned and tucked in nicely ...

So I yanked it out, put in a new PCB, jammed the wires in which ever way they would fit and tested it, then sealed it up. You'll just have to take my word for it, it could have looked nice.

I am fairly certain as I continue to put these things together, more magic will happen. I guess I better hurry and test them all so I can fugure out how much reordering I need to do before Thanksgiving.

By the way, has anyone set their lawn on fire yet doing this stuff?

[stempile]

I would test it before putting in side the case. Avoid have to take everything apart if there is a problem.

ms

[scharbon]

Now you tell me!!!!. Actually, I figured out an easy and quick way to ground hop each PCB without casing them. I will be doing that tonight and tomorrow. My original concern was having the exposed circuit on the ground (fire and what not) - then I realized I am testing on concrete :oops: . So that concern vanished.

Slowly but surely I am getting less dumb as each day passes!!!

Steve

[sandy]

Quick,
push the smoke back in!!!

[Sean Bowf]

Makes sure all the pins of the TRIAC have traces going to them too. If you are missing one of them, the resistor will be trying to carry the load for the attached lights...which it can't handle.

Sean

[wjohn]

notch that one up to a test of magic smoke, me thinks.

My guess, and it is only that, would be R2 took the full load of the lamps before frying out, cause would be a faulty TRIAC IMHO.

The PCB should be recoverable, replace the MOC, Resistor and TRIAC in Channel 2, test for shorts/ open circuits and reapply power. If it does not work after that, bin it ;-)

[FireGod]

Last year I had a brand new triac smoke a resistor so, of course, I thought I did something wrong. I replaced the resistor and triac driver. It smoked again. In the end it was a bad triac from the factory. So it can happen. It can also be a small strand of wire from when they were trimmed. That will cause some big problems.

Lately, I have had a couple of $10.00 I/Cs bad from the factory. They make mistakes too.

[klanger]

Did the smoke come out in sequence with the music? :D

[ErnieHorning]

It’s possible that you just had a bad part. That’s why we often refer to the first power up as ‘The smoke test’. This phenomenon also provides a source of amusement for us older guys that have seen way too many non-eventual power-up’s. It’s a rare enough occurrence that many others typically flock to ground zero to admire the event and rate how well you did.

This is also an opportunity for celebration, that you didn’t mistakenly perform ‘The Blam test’. This is where a trace is not only opened up; it’s completely removed, as though it never existed.

[Wayne J]

This is also an opportunity for celebration, that you didn’t mistakenly perform ‘The Blam test’. This is where a trace is not only opened up; it’s completely removed, as though it never existed.
http://i4.photobucket.com/albums/y122/MERC460/smileys/blowup-1.gif


8)

[scharbon]

I was about to pitch the PCB until I read John's post. Decided I had nothing to lose - and guess what - I didn't lose Nuthin!!! ('cept for a 180 Ohm resistor and a triac). This was the first time I have ever unsoldered a board and it was easier than I thought.

This time I tested all channels and they worked :D .

So Sandy, I guess I was able to push the smoke back in!

Thanks for the help guys. For those of you wondering, I think Phil said it could be a bad connection on the middle pin. Ernie said it could be a bad triac. While more than likely it was what Phil said (given my skill level) I am sticking to Ernie's recommended cause (That's my sotry and I am sticking to it).

Steve

[sandy]

I was just humming some Deep Purple,
Smoke back in order
some lights in the sky . .

[synnie]

Its good to see that im not the only one who smokes resistors...lol...read the article a while ago, went into shed and rechecked all solder joints on the PCB's tested them all..no problems.Just outside now testing lights and hooked up one of the SSR's...no lights but smoke instead....i had one SSR i hadnt tested because it was in the house from when i was first hooking all the controllers and power boxes up. They do smoke up nicely...back to the soldering iron

[Wayne J]

They do smoke up nicely...back to the soldering iron

:shock:

At least you enjoyed the show. :P

[synnie]

At least at 24V they dont go flash bang. just a nice little warning smoke up to start with