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Mechman Alternators

How to calc hp draw from you alt


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Amps x Volts = Watts

Watts / 745.7 (one HP) = Electrical HP Produced by the Alternator

HP x 15% Efficiency Loss = HP Loss

HP + HP Loss = Total HP Used

Example:

57A x 14.9V = 849.3 Watts

849.3 Watts / 745.7 = 1.14 HP

1.14 HP x 15% = 0.17 HP

1.14 + 0.17 = 1.31 HP Total

I found this on the net. I have no idea how accuate it is.

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It actually depends on the electrical load on the alternator. When the vehicle is running with no additonal electrical load against the alternator, it will consume the same amount of HP as your stock alternator. The more amperage you draw from the charging system, the more HP is required to turn the alternator.

When putting out Max 220 amps, it will require about 5 hp to turn. The less amperage you use, the easier it is to turn.

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Thanks Mechman i was wondering that my self.

*sorry to thread jack*

so a ballpark would be somewhere around 40 to 44 amps per hp??

Edited by 01VWGREENMACHINE

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