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HOW MEGAPULSE SAVES STARTER MOTORS
& ALTERNATORS ON TRUCKS
STARTER MOTORS: A sulphated battery can lead to premature starter motor failure due to excessive cranking.
Because a sulphated battery cannot deliver the full current required by the starter motor, it turns slowly. Slow cranking leads to longer cranking times, as a diesel engine takes longer to start. This overheats the starter motor leading to premature failure.
Interesting note: Many light aircraft specifically restrict cranking time to 30 seconds, and if the engine has not started in this time, the pilot must wait for 5 minutes or so for the starter motor to cool down before trying again, specifically to prevent starter motor failure.
ALTERNATORS: These graphs show why a sulphated battery can lead to premature alternator failure and the loss of electrolyte due to boiling off from an overheated battery.
A healthy battery with no sulphation charges quickly after supplying the starter motor with a short burst of 100's of amps.
The low internal resistance permits a high recharging current, here shown initially at 90 Amps. So the battery quickly regains the charge lost during starting. Within 30 seconds or so, the current has dropped to 10 Amps, and within 90 seconds it has dropped to less than 1 Amp (green line).
At this point the alternator has completed the bulk recharging of the battery and has nothing more to do, except maintain a low power, low current trickle charge and match the current drain of the vehicle's electrical system.
Note: this chart uses typical values to illustrate the general principle
This graph shows the situation after one hour.
The high internal resistance of the sulphated battery limits the maximum charge current to 7 Amps in this typical example.
Because a sulphated battery never reaches the maximum fully-charged voltage of a healthy battery, the alternator continues indefinitely to charge at 7 Amps, leading to overheating of both alternator and battery (red line).
After 2 hours, the power delivered by the alternator to the sulphated battery is 38 times greater than to the healthy battery.
Note: this chart uses typical values to illustrate the general principle
Megapulse prevents sulphation, thus prolonging the life of alternators, starter motors and batteries.
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