I just added a second PID and 25 watt SSR to my previously built setup. Although my project box had vent slots in the back I went with the externally mounted heatsink: https://www.auberins.com/index.php?m...roducts_id=244
The SSR is normally mounted in the center of the much larger heatsink. The heat sink is large enough to mount (2) 25 AMP SSRs side by side after drilling and tapping new SSR mounting holes.
I wonder/worry if the single 25 AMP specific heatsink is adequate for both 25 AMP SSRs operating simultaneously. The 25 watt SSRs seem like overkill for our low watt/AMP lead pots or hot plates. Being on the low end of the SSR's capacity does that mean less heat being generated? Or does the number of on/off cycles generate the heat? Is there a high temp failure point for SSRs? I was thinking I could monitor the SSR's temperature by checking the heatsink with a thermal gun?
I think I'm ok but thought I'd throw the question out there.
edit added: I see the cut in temp for a cooling fan is 113 degrees. I suppose any temps over 113F are approaching component critical temps. https://www.auberins.com/index.php?m...ort=20a&page=2