I do get some massive voltage dips. Today I measured the AC with the DC and I noticed that that when I see voltage dips on the AC line I also get coinciding transients on the DC portion.

I understand that the sudden in-rush of current into the AC motor (especially when starting four at the same time) is causing a huge draw on the power lines up to the point that my supervisor chip is resetting my uC.

I will start looking into how PLC's handle this but would you guys have a suggestion on where to start looking? Keywords? Brands?

I have also been looking at DC-DC power supplies that are used in the automotive world for powering computers. I have noticed that they use something called a buck-boost converter for helping the computer survive engine cranking. Do you think that these buck-boost converters (although expensive) could help me solve the problem?

Thanks for the help thus far,
Roque