|I know this is not an Alternator Rotor |
But you get the idea..
My initial intention of adding the 'Small Alt' mode selectable via the DIP switch was to protect smaller framed alternators from prolonged periods of high current output. Ala, that 200A Hot-Rodded alternator in a standard small frame.. Small Alternator mode will cap an alternators output to 75% of its capability (configurable of course), at all charge points. But it seems perhaps more might be needed - especially given the real life experience of someone melting down my beloved Leece Neville large frame alternators just idling around...
So, I have added a new feature to further restrict how hard the field is driven when the engine is at idle. By sensing this RPMs vis the Stator wire, I can tell when we are near idle - or at least near the lowest RPMs that the engine has been operated at.. And when at idle I now cap the field to 50% of its max drive. This % is increased up to the max allowed (100% or 75% depending on the DIP switch, and if the defaults have been adjusted). And there is a new parameter in the $SCA: command to configure this capability.
|Blue line shows default idle capping curve. |
Red and green give an idea of some other configurable options via the $SCA: command..
I hope this will help out some installs. Though we never had any issue pulling max amps (and max field) for several hours at a time while idleing around during Christmas Ships with our LN 4900 270A alternator, clearly someone has.. Perhaps I can feel even better now - protecting the Alternator just a bit more...