[bwilson4web]

I was thinking about this at lunch and realized the deep-cycle battery only has to provide the 90% load over the time, vehicle base load, and let the vehicle inverter with diode handle the peak loads (aka., rear window defroster, windshield wipers, night driving lights and brake.) Anything over that would drop the output voltage and the inverter would then provide the make-up or peak power. For example, you measured ~20 A. in your first test. Add whatever you consider to be additional, standard load plus 5-10% and that would be your deep-cycle battery DC-DC converter design goal << 100 A. <grins>

This also, in theory, means we can lighten up the power diode, forward current limit and use a less expensive part. However, there are tons of automotive alternator diodes out there that should easily be within this range and quite affordable.

One other thing, the vehicle ECUs use 'cheap' DRAM for persistent memory. What this means is losing the 12 VDC wipes out not only the clock and radio stations but also the ICE Lambda constants. Many have noticed that it takes a couple of runs before the Prius 'relearns' these values and becomes more efficient again.

Bob Wilson

ps. CBS3502412 (300W) or CBS3504812 (348W) would be a very nice converter and Allied sells them $171.53 ... <hummm> Also, the TI PT7750, 15A is another nice part. Then there is is Ebay part: 160381658887 ... sounds too good to be true.