Re: Let's discuss Packard 6V electrical systems and the change to 12V systems

Posted by Peter Packard On 2008/6/21 2:29:55

G'day all, especially PackardV8, I understand that the largest British manufacturers such as Austin and Morris went for 12V initially. These cars were widely exported and we got lots sent to Australia. Almost all British (and early Japanese) motorcycles were 6V but varied in polarity. Marchal in France was 12 V and to my reading, most Packards exported to Europe in the 1930's were converted to 12V Marchal or Lucas. ( Lucas, the Prince of Darkness and widely held as the inventor of the short circuit and open circuit) I have not had a chance to chase up the SAE article on 6V versus 12V systems but I seem to recall that the main reason for changing to 12V was the ignition voltage required for higher compression engines. As to the settling on 6V, I understand that the SAE in America was always working toward standardisation and as electrical systems became more prevalent on vehicles in the Nineteens, 6 V was accepted as the standard for a number of reasons. 6V lighting systems are supposed to be better than equivalent wattage 12 V systems as the filament is shorter and located closer to the focal point of the reflector. 6V bulbs were thus less prone to filament failure on the usealed roads of the time. I repeat that I am not implying that the US was slow to convert to 12V. 12v batteries are also more prone to tracking and loss of charge if the top of the battery is wet.