arcturus; See:
http://www.sw-em.com/Fuses,%20Alloca...m#Fusing_Rules
Clan; ...but Current is what does the work...no current, no work...perfect example is Derek's duff bat.
Derek; The Voltmeter you measured that Bat with, drew an extremely low and insignificant amount of current, so it measured the surface charge voltage just fine...but once the significant current required by the Starter is drawn (and we want to do some work), voltage collapses to nothing...that is why a Load Test is what should be performed on a Bat...it takes into account the internal resistance of the Bat...which should be quite low, so that when high current is drawn, only very little drops across its own low internal resistance, and almost all voltage occurs across Load...
Cheers