So i upgraded my mighty mini to a 14s 4p 25r's i bought a new vruzend bms the old one blew a fuse. as i was connecting the bms harness to bms it sparked and popped wich melted the negative post and the bms. I checked to make sure the battery was hooked up correctly and could not find any problems with it. This is two bms's that seemed to have self destructed. Not sure whats going on here, leary of buying another bms. Any one have any idea as to why this happened?