Dimmer @full

[FHSAUD]

HI all,
I have an old cd80 analog pack (2.4x12) there was one dimmer ghosting @ 20% or so. I pulled the cover and found the ssr for that dimmer had melted down. replaced the ssr and now it ghosts at full. Where should I look next?
Not sure a "Carpenter focus" will help this one.

 

[Footer]

Check your polarity on your control lines, you might have reversed them.

 

[cutlunch]

I haven't worked on one of these or seen the circuit diagram for one.

However from experience I would suggest you start at the SCR and work through the control circuitry.

When an SSR melts down it can take out anything connected to the gate, because the gate circuit is normally low current compared to the main terminals. And if your SCR got hot enough to melt then I would expect collateral damage.

. I am not sure if these were connected from the control circuit by a DIAC , pulse transformer or opto- coupler. I would compare the control circuit of a good channel to the faulty one and you should be able to find the faulty part(s). Did you check the PCB for any burned tracks?

Sorry I can't be more specific but this is where I would look faced with the same situation.