Message text written by "Michael D. Porter"
>I would say that something similar is happening in this case, since
if the alternator were providing sufficient current to run the field
enough to load the engine, that would compensate for an additional
load on the regulator wire circuit, which the poster says it does
not--when the heater is turned on, the car dies. The alternator
obviously isn't compensating for the internal voltage drop in the
regulator when the heater turns on.
OK, going out on a limb here but most alternators/regulator combinations
are self-exciting in that the power to run the field comes directly from
the alternator output (via the rectifier assembly) and as long as that is
running the alternator will put out until it stops spinning.
Except for the alternators using the new breed of voltage regulator chip
which has an input (switched power) that will shut down the alternator.
These chips also monitor the AC alternator output and will switch the field
off if the frequency drops to zero (engine stopped).
It is possible that the poster has just such an alternator/regulator
combination and Michael might be right.
But that is just a guess.
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