You don't actually have a "real" alternator
. What you have is a rotating maget passing by a coil. One end of the coil is "ground" and the other goes to a single
The concern is that unloaded, it might be possible for the coil to develop a large enough voltage spike to exceed the diode reverse voltage rating. If you get any charge current
at all (probably is only rated for around 6A max anyway) then you are good.
For long engine run times it is possible to gas a battery with such an arrangement if the battery is full. If you need to regulate the output you must use a shunt regulator
, which regulates by passing current
directly to "ground" without hurting the charge coil. Other types of regulators are series regulators in that they drop excess voltage acrosss the active switch inside and, therefore, are not suitable for loading the coil. A good shunt regulator
will allow you to run without a battery and not worry. Of course a 24V lightbulb will also work.