The discussion on IT power systems has returned me to a subject which has caused problems for some time. In Australia TT and IT power systems are not allowed, and a PE is always provided. This makes life relatively straight forward locally, but as some of our equipment has features which rely on this situation, it causes problems when we export products where the power systems are inconsistent.
A main problem is that there is a general lack of appreciation that the equipment requirements can vary depending with the power system. It is also common that a customer, often including technical types, are not even aware there are different types of power systems. Now it is possible to make most equipment double insulated and compatible with almost all requirements for the different systems, but for some types of equipment this requires a reduction in functions or features in the equipment, or versions with different implementations. There are a number of lists available on the net which list voltages and even plug types for various countries, but we really need some more details, including; PE availability (always, where required or installation specific, rarely) Power System (TN-(C, C-S, S), TT, TI other) Voltage tolerance. Is any one aware of a comprehensive listing of this nature? >From the discussions re Norway, it appears that would be a useful tool. Chris Healy Liaison Manager, Standards and Approvals email : [email protected] JNA Telecommunications Limited Ph (direct) : +61 2 9935 5728 16 Smith St, Chatswood, NSW 2067 Fax : +61 2 9417 3862 AUSTRALIA
