▁for ▁qual ifying ▁and ▁ 1 2 ▁vol ts ▁under ▁racing ▁conditions . ▁ 1 : 3 2 ▁racing ▁is ▁between ▁ 1 2 ▁and ▁ 1 6 ▁vol ts ▁depending ▁on ▁type ▁of ▁car . ▁Most ▁HO ▁rules ▁require ▁tracks ▁to ▁provide ▁voltage ▁between ▁ 1 8 . 5 ▁and ▁ 1 9 . 0 ▁vol ts , ▁and ▁at ▁least ▁ 5 ▁am per es ▁per ▁l ane . ▁C ertain ▁European ▁ 1 / 2 4 ▁" scale " ▁racing ▁events ▁use ▁ 1 8 . 2 ▁to ▁ 1 9 . 0 ▁vol ts ▁DC . ▁ ▁Many ▁tracks ▁use ▁banks ▁of ▁lead - ac id ▁batter ies ▁to ▁produce ▁sufficient ▁high ▁amp ▁DC ▁power , ▁but ▁in ▁recent ▁years , ▁relatively ▁in exp ensive ▁high - quality ▁electron ically ▁reg ulated ▁power ▁supplies ▁have ▁become ▁more ▁popular ▁to ▁achieve ▁consistent ▁and ▁clean ▁power . ▁ ▁Compet ition ▁formats ▁ ▁Several ▁race ▁formats ▁are ▁employed ▁in ▁competition ▁as ▁time ▁allows . ▁The ▁quick est ▁to ▁run ▁is ▁called ▁round ▁ro bin , ▁which ▁can ▁be ▁run ▁in ▁either ▁of ▁two ▁ways . ▁The ▁first ▁( and ▁least ▁common ) ▁way ▁is ▁begin ▁with ▁one ▁driver ▁on ▁one ▁l ane ▁of ▁the ▁track , ▁a ▁segment ▁usually ▁consisting ▁of ▁ 2 ▁minutes ▁is ▁run ▁in ▁which ▁the ▁driver ▁attempts ▁to ▁complete ▁as ▁many ▁la ps ▁as ▁he ▁can . ▁ ▁The ▁second ▁( and ▁most ▁common ) ▁way ▁to ▁run ▁a ▁round ▁ro bin ▁is ▁to ▁have ▁four ▁drivers ▁(