Main bus is fed by both alternators and the battery; no isolation.  I know that Regulator 2 is too high (28V at the moment), and I'm going to adjust it; but it wasn't doing that when I bought it; neither was the original Regulator 2; so I'm also looking for a common factor that seems to have made two successive Regulator 2 units start kicking in when they shouldn't.  

OK, two votes say the Whelens probably have a cyclical draw; if anyone knows different or has any hard data, please squawk.  What I've observed is Alt 1 amps going up and down 3-4 amps, and I guess that's normal.  Thanks guys.  -- CB

On Feb 17, 2013, at 5:03 PM, Colyn Case wrote:

Charley,

I haven't examined the Whelen strobe controller but it wouldn't surprise me if it had more draw right after the flash.  

What is the setup between alt 1 and alt 2?   Do you have them both feeding the same bus?  If so, maybe increasing the spread (e.g. make alt 2 .2 V lower than alt 1) will keep #2 from cycling on and off all the time.    (I have a 2 bus system and run some items off of alt 2 and others off of alt 1 with critical systems fed by both through diodes.   The diodes mean I have a soft failover if alt 1 fails but the spread means that alt 1 carries the load normally for those items that are fed from both sides.   The separate busses mean I find out as soon as it happens if alt 2 is weak...and then I can go to cross feed).

Colyn