Hi Bob,

 

Tracy will have to weigh in on this, but here is what I see.  When the EC2 (20B version) was using the electromechanical relay: when the signal from the controller was off, the relay would conduct to the secondaries because it was wired to the NC (normally closed) contacts.  The MOSFET SSR (solid state relay) is considered to be NO (normally open), so without energizing the relay it will not conduct to the secondaries.  Unless I am missing something, Tracy will have had to change the logic in his program to reverse the state of the signal line so it would function properly with the SSR rather than the electromechanical relay.  If I have this correct that means that one can not switch from one relay type to the other without have the program updated.  In all EC2 matters, Tracy is of course the final authority. 

 

That said, the relay would only effect the secondaries and you should still have all primaries firing.

 

Joe