I've had no problems with it at 2 amps. The drivers do have to be ALL the way in to the sockets though. I've had issues with them if they are only most of the way in. These drivers are possibly more prone to die for various reasons than Pololu drivers though so I like the ease of replacement of a socket solution. For instance, wiring a coil between a and b outputs (cross wiring) will kill a driver pretty quick. As does incorrect power-on sequence. (enforced by power relay on Sanguish) Once you have wiring and stuff set up right, they seem to be pretty robust to me. I think the run time failures reported on the web at some CNC sites seem to be due to using too high a voltage. I would recommend no more than 24V. You want plenty of headroom between run voltage and max voltage.
I think the only real issue at 3 amps vs 2 would be cooling. I'd guess you could get by with just a fan, though some heat sinks might be advisable. The drivers will handle 2 amps in still air but they do get hot at that setting, the thermal protection doesn't kick in though. With a fan they stay pretty cool even without a heatsink.
I think the only real issue at 3 amps vs 2 would be cooling. I'd guess you could get by with just a fan, though some heat sinks might be advisable. The drivers will handle 2 amps in still air but they do get hot at that setting, the thermal protection doesn't kick in though. With a fan they stay pretty cool even without a heatsink.