Are DC currents in an AC power distribution the root cause for some abnormalities in AU?

Abnormalities within a limited number of small and medium enterprises (SMEs) in Australia are reported. A set of interrelated industrial issues are brought out in order to advance the state of knowledge and avoid similar abnormalities/irregularities and to bring back some ideas for the mitigations. Impacts on new automated systems and on industrial as well as safety standards are expected in the long run.