SSR Problem

[Peetem]

My SSR was working fine but now even when the PID isn't sending it voltage (i.e., the led on the SSR isn't on), it still allows 120vac to pass. Any ideas what could be the problem?

Thanks!

[richiem]

Its power switching element is shorted, a common problem with SSRs, especially ones that run too hot. It's the reason that I recommend that all SSRs be put on heat sinks when they are supplying more than 10 or 15% of their rated current. Get a new one. Over rate the current a lot -- if you're controlling 13 Amps, get a 60 Amp SSR, and heat sink it.

[Peetem]

Its power switching element is shorted, a common problem with SSRs, especially ones that run too hot. It's the reason that I recommend that all SSRs be put on heat sinks when they are supplying more than 10 or 15% of their rated current. Get a new one. Over rate the current a lot -- if you're controlling 13 Amps, get a 60 Amp SSR, and heat sink it.

Fortunately mine (both of them) has heat sinks.

I found the problem. I was measuring the output when it wasn't under load. Once I added the load (heater on one and pump on another) the SSR worked perfectly.

[richiem]

AHA!

[scrubjaysnest]

I can't seem to find anything on the site that tells which heat sink goes with which SSR. For example which heat sink would one use for this ssr ESSR-25DDC