🚀 go-pugleaf

In article <1990Oct15.202407.13654@mthvax.cs.miami.edu> wb8foz@mthvax.cs.miami.edu (David Lesher) writes:

>NEVER disconnect the battery on a running car. This is referred
>to as a "load dump" and generates the worst possible transient
>voltages. The battery is an essential low impedance element at
>frequencies above DC. Without it, the inductance of the field is
>such that the electronics will be history before the voltage
>regulator can get things down to where they belong.

>The best way to avoid problems is patience. Hook up the cars.
>Sit and let the weak one charge for a while. (10 minutes maybe)

This will give better results, and is practically essential in very
cold weather.  The jumper cables will simply not carry enough current
to start a car -- a typical jump works by charging the "dead" battery
somewhat so that the "dead" battery assists in the starting.

>Once the other car is running, you can let the good car idle
>down, and maybe if you want, turn on all of its loads: headlights,
>heater, etc. Then disconnect the cables.

It is best to disconnect the jumper cables shortly after the "dead"
car has been started.  Leaving the jumper cables connected when both
cars are running makes the alternators "fight" one another for the
correct voltage.  This is generally best avoided, but it won't do any
harm for short periods.



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