Leece Neville 555. surge protection ?

[thomasonw]

Hello.  I had just the same experience when I assembled our small DC generator, was able to lug down and stall the engine with the load the alternator placed on it.   For a while I used one of the Balmar alternator regulators and its 'belt saver' features to limit alternator output.  It worked well, but the choices were a bit crude.

After a while I built a custom controller to run the engine and the alternator;  one of the key features is it measures Amps produced in addition to voltage.  This way I can accurately control the max load placed on the engine preventing any stall out.  Have also recently completed a simpler design with just the alternator regulator (sans the engine controller portion); it still retains the amps measurement a capability.  As a bonus, by measuring Amps am able to measure the state of charge in the battery, making sure to stay in Acceptance phase until the battery is truly fully charged.  Both are open sourced / free to use and I have some group-buy PCBs left over if you are interested:

http://smartdcgenerator.blogspot.com/
http://arduinoalternatorregulator.blogspot.com/