The BT551 START-STOP is an easy-to-use highly precise professional battery tester with an integrated printer. Multifunction device, it can perform 3 types of tests :
6-12V battery (tests voltage & charge state, cold cranking Amps & battery health etc)
12-24V starter motor (tests starting voltage - cranking voltage test)
12-24V alternator circuit (tests no load voltage and charging voltage as well as current undulation (ripple) during the charge)