I havent heard of any real failure like this on the AS332
There has been at least one real case on the Sea King, caused by both rectifiers failing (one was known about, the other was masked by a complex internal fault which saw the remaining rectifier push out just enough DC to keep the caption off but insufficient to charge the battery). The battery then failed unexpectedly which led to simultaneous failures of a number of systems including both fuel computers. Unlikely this will happen again, on a Sea King or any other type, but never say never!