Analyze alternator output capacity vs total electrical load to determine if the charging system can maintain battery charge.
Input Parameters
Results
--
Actual Output at RPM
A
--
Load Percentage
%
--
Charge Surplus/Deficit
A
--
System Status
Note: Alternators only produce rated output at high RPM. At idle (600-800 RPM), output may be only 30-55% of rated. LED headlights and electric fans reduce load significantly vs halogen/mechanical.
Reference
Alt RPM = Engine RPM × Pulley Ratio (2.5 typ.)
Output % varies with alt RPM:
<1500: 30%, 2500: 55%, 4000: 75%, 6000+: 100%
Actual Output = Rated × Output%
Surplus = Actual Output − (Load + Battery Charge)