clearchris:
So, I know that SSRs tend to "fail closed". What does this specifically? Does it mean that it's going to short across the poles? Does it mean the circuit will remain closed so the heating elements end up frying themselves? i have seen a mention of using i2t fuses, but what's the point of this? It sounds like i2t fuses help protect the SSR, but don't help in the event of a failure, do they?
Anyone have any suggestions so I can sleep at night?
In my experience, they fail "open" -- open circuit.
A good quality module should only fail, IMHO, if subjected to abuse but not from use.
See "Emphasis on Quality" -- Opto22 - About Us
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