Converting Delco 22Si to external regulation

[Singularity]

This will not be a technical post per se.

EVM1024 created an excellent thread that inspired me to look for a 28si alternator to convert to external regulation while looking for an alternator solution in a 12v to 24v conversion:

http://www.cruisersforum.com/forums/...on-204361.html

My goal was similarly to have a medium-duty truck type alternator to run at de-rated capacity. I came across a good deal on a 22si ($75, so I bought two). At 24v the 22si produces 70a (140a 12v equivalent). The 22si is also a J180 frame with internal regulator and diodes.

I could not find much information on the 22si other than they can run hot. Insofar as solar is my primary electric source with a diesel genny backup I see the alternator as deep backup. When coupled with a newer external voltage regulator (e.g. Balmar 624) the alternator can be set to operate at reduced production/temperature mode, which is where I plan to set it for everyday operations (after full check---out). I can always ramp production in anger if need be.

A benefit of the 22si in conversion to external regulation is that the posts on the back of the frame can be preserved after removal of the internal regulator. A local alternator shop charged $30 per alternator to remove the internal regulator and wire the field to the "I" post on the back of the frame, with the R post on the frame preserved for the stator lead. With more time/interest someone could rewire it themselves (without having to create an external board/posts as with the 28si conversion).

[aquabelle]

Very helpful information....thanks for posting. It's been a while: any feedback on how the 22Si performed under external regulation? Did alt heat result in serious output throttling?