0 5 ▁differ ed ▁from ▁previous ▁pro tot ypes ▁in ▁the ▁way ▁that ▁it ▁had ▁a ▁both ▁complete ▁AC ▁and ▁DC ▁equipment , ▁previous ▁locomot ives ▁only ▁having ▁a ▁complete ▁AC ▁equipment ▁and ▁a ▁small ▁DC ▁equipment , ▁limit ing ▁their ▁power ▁under ▁ 1 . 5 ▁k V . With ▁a ▁full ▁AC ▁and ▁DC ▁equipment , ▁BB 2 0 0 0 5 ▁developed ▁nearly ▁ 8 5 % ▁of ▁its ▁power ▁under ▁ 1 . 5 ▁k V , ▁which ▁was ▁a ▁great ▁achiev ement ▁at ▁that ▁time , ▁knowing ▁that ▁only ▁ 2 ▁years ▁before ▁BB 2 0 0 0 4 ▁developed ▁only ▁ 4 5 % ▁of ▁its ▁power ▁under ▁ 1 . 5 ▁k V . ▁ ▁The ▁prototype ▁helped ▁to ▁develop ▁the ▁bog ies ▁of ▁the ▁ 2 ▁'' ▁series : ▁the ▁BB 2 5 1 5 0 ▁series ▁which ▁had ▁bog ies ▁for ▁ ▁and ▁were ▁lower ▁ge ared ▁( to ▁pull ▁heav ier ▁fre ight ▁trains ) ▁and ▁the ▁BB 2 5 2 0 0 ▁series ▁which ▁had ▁bog ies ▁for ▁ ▁and ▁were ▁higher ▁ge ared ▁( for ▁l ighter ▁passenger ▁trains ▁and ▁to ▁operate ▁in ▁push - pull ▁mode ). ▁ ▁References ▁▁▁ ▁Category : Al st om ▁locomot ives ▁ 2 0 0 0 5 ▁Category : Ex perimental ▁locomot ives ▁Category : R ail way ▁locomot ives ▁introduced ▁in ▁ 1 9 6 1 ▁Category : Multi - system ▁locomot ives ▁Category : Standard ▁gauge ▁electric ▁locomot ives ▁of ▁France <0x0A>