They shouldn't blow up on insufficient voltage, just stall. You probably have a crossed wire somewhere that's feeding too much power.Do all GT machines blow up if they don't get enough power (32 EU/t, 128 EU/t, 16 EU/t, whatever)? At least my plate bending machine already blew up two times (it was connected to 3 solar panels -> 3 EU/t) and at first I didn't even know why. Is there a way to prevent this from happening (I heard this also happens if they idle?!), e.g. with a small upgrade or anything like that?
If your machines are outside it's also quite possible they got rained on and exploded because of that.