Let me start by saying the SSR-60DA is a beast when it comes to handling high current AC loads. I've been using it to control my workshop's dust collection system (similar to one reviewer's CNC setup), and when properly installed with its heatsink, it performs flawlessly.
The first thing you need to know: NEVER skip the heatsink! I learned this the hard way - my initial excitement made me overlook this crucial requirement, resulting in a fried unit within hours. The epoxy encapsulation might look tough, but this relay generates serious heat even at moderate loads.
What impressed me most was the complete silence during operation - no annoying clicks like mechanical relays. The zero-cross triggering works perfectly for my sensitive equipment, eliminating those nasty power surges. Installation was straightforward, though I'd recommend using quality thermal paste (not included) for optimal heat transfer.
However, there are some significant caveats. Multiple users report overheating issues even at 1/3 of the rated load. In my testing at ~40A continuous load, the heatsink reached concerning temperatures (150°F+) within minutes. While it kept working, such temperatures definitely shorten component lifespan.
The strangest issue I encountered matches one reviewer's experience - occasional failure to turn off completely when DC control voltage is removed. This seems to happen more frequently with inductive loads. My solution was adding a bleeder resistor across the output terminals.
Final verdict? It's a decent SSR for intermittent or low-duty-cycle applications up to about 50% of its rating. For continuous high-current use, look for alternatives with better thermal performance or plan for active cooling. Always monitor temperatures during initial operation!