DiyLightAnimation

Hardware => Lynx SSR4 => Topic started by: Ron on November 25, 2012, 04:55:00 pm

Title: SSR4 Resistor Burned
Post by: Ron on November 25, 2012, 04:55:00 pm
I have an SSR4 DMX version that one of the 180 ohm resistors fried on today.  I don't think it could be the opto coupler, so I'm thinking it has to be a bad Triac.  Does that seem reasonable?  That's pretty much all that is left to check.
Title: Re: SSR4 Resistor Burned
Post by: tbone321 on November 25, 2012, 04:58:41 pm
It could be the triac.  Sometimes when they fail they draw the full load thru the gate which is what the 180 ohm resistor is connected to. 
Title: Re: SSR4 Resistor Burned
Post by: Ron on November 25, 2012, 05:05:05 pm
That's what I was thinking.  Just reread and forgot to say I replaced the resistor first since it was easiest and I could find another one.  The new one burned too.
Title: Re: SSR4 Resistor Burned
Post by: n1ist on November 25, 2012, 05:29:13 pm
Check the soldering on the triacs.  They are connected to traces with a lot of copper on them and it can be tough to get a good solder joint,  If the triac is not connected, all the current will flow through the opto and 180R resistor.
/mike
Title: Re: SSR4 Resistor Burned
Post by: RJ on November 25, 2012, 05:40:11 pm
You are not allowed to view links. Register or Login
Check the soldering on the triacs.  They are connected to traces with a lot of copper on them and it can be tough to get a good solder joint,  If the triac is not connected, all the current will flow through the opto and 180R resistor.
/mike

This is the normal reason this happens. I have seen it a couple of times and it was always because of a bad connection. on the triac.

RJ
Title: Re: SSR4 Resistor Burned
Post by: Ron on November 25, 2012, 11:20:42 pm
I'll check that later but I think this one has worked the past couple of years.  Just started acting up I believe.  Any way to test the Triac?
Title: Re: SSR4 Resistor Burned
Post by: tbone321 on November 25, 2012, 11:35:39 pm
There really is no need to test it.  Unless one of the joints has failed, the Triac has to be bad.  I would use your ohm meter and check to make sure that the solder joints are ok and if they are, then the triac is toast.  I would probably replace the opto as well since it took a few hard hits as well.
Title: Re: SSR4 Resistor Burned
Post by: Ron on November 26, 2012, 12:27:40 am
Mike and RJ got it right.  Shoddy soldering on my part after a closer look.  Fixed the resistor and retouched the Triac and all appears to be working well.

I can also say I love my Bobcat DMX tester, great tool.

Thanks gentlemen for your help.

Ron