Not sure whether or not this is a bug, but it seems that, regardless of the output of the energy source, if the cable used to transfer the power is a higher tier than the machine or power storage block that takes it, the machine/storage block will explode. This first happened when I tried to connect my Battery Box (a Low-tier storage block) to my Low-tier machines using Glass Fiber Cables. My Grinder blew up as soon as I tried to use it. This happened consistently.

Conversely, directly connecting higher-tier outputs to lower-tier inputs using lower-tier cables worked perfectly fine.