Edited PS: Also in Btech PPC's HAVE minimum ranges, where if you fire them at that range there is a very real possibility of an electrical backlash from the target to the cannon, causing all sorts of nasty things. I think it was something like 3 hexes, or 90m.
If you fire a PPC at point blank and its aoe hits you then you at least loose your infrared for a little bit, and maybe take some damage. To be honest I'm too busy cursing myself for shooting too close to notice if I take damage.
