Rodders, MJ, High Peak thanks very much I appreciate your input it all inter relates with Mr P.. .. .Mr Pilcher your vital source of information has made the penny drop <img border="0" title="" alt="[Smile]" src="smile.gif" /> . The DC produced by the Alternator through the Transformer Rectifier untit will self exite the field winding, hence not needing the DC from the battery (which is only used to get it going). Thanks very much, that has been giving my small brain pain for the afternoon, like you say so simple.....mmmm what does that say about me!!? <img border="0" title="" alt="[Eek!]" src="eek.gif" /> . .. .Cheers, much appreciated <img border="0" title="" alt="[Big Grin]" src="biggrin.gif" />. . . . <small>[ 14 March 2002, 08:39: Message edited by: CAT3C AUTOLAND ]</small>