I was wondering if anyone could help me. I am a qualified Electrician in Australia and have done domestic work over the last 10 years. I have never had exposure to the wiring or contactors and relay's, timers and overloads. I can just navigate my way through drawings after some time. I understand the basics of Electricity very well but this is a grey area for me. Does anyone know of a site or text books that offer training in this area?