For those of you in the know, is it
normal for an alternator to seep current and get warm when the field coil is
powered up? Is this something I need to fix? If so, should I
cancel my trip? I think it has probably been going on for a long time
but...
The field current is controlled
by the regulator, which is usually internal. The regulator will only allow
field current if the armature is spinning and bat. below about 14 volts. A
small amount of current is allowed at start up via the little red light to
give initial voltage.
Ian Beadle.
Ian;
With the
alternator not running, the battery voltage will always be below 14 volts;
even with the charger on, so the field current will flow. Dave has
modified the internal connection the same way I did to provide external feed
to the field windings. This does not run through the warning
light. So with battery voltage to the field, alternator not running; I
estimate it will draw 2-3 amps. Plenty to make the alternator pretty
warm after awhile.
Also, I don’t
think tripping a 5 amp breaker in field circuit indicates anything
wrong. With the battery a bit low and a, say, 60A alternator spinning,
the field could draw 5 amps. I use a 7.5A breaker on my field current
circuit.
Al
There should be a
relay connected to D on the alternator, this ensures that the field is
only powered when the alternator is
spinning.