Join Date: Apr 2006
Thanked 181 Times in 178 Posts
Rep Power: 13
A little more news trickles in:
First, that PWM makes a difference in charging--but that difference also depends on charge state (aka SOC) and no one wants to comment beyond the Morningstar/Sandia report.
Second, that some alternators supply PWM, but others still supply DC, and again, no makers want to comment, apparently there is a Cold War going on in charger/alternator technology, still.
Third, Cam take note, that during the "bulk" phase amperage is more important than voltage, and the charging algorithm used by BS very definitely favors supplying more amperage at lower voltage, which explains why I wasn't seeing 14.4 (or 13.6) during that phase.
Fifth, the BS controller may be 97% efficient at 24v versus 95% efficient at 12V (input voltages) so setting the panels up for 12/vs/24 volt input won't make much of a difference...although, if setting them up for 24V allows me to gain an extra hour of charging under load--that will be interesting. Haven't had a chance to ask BP about the effect of removing the diodes (since the BS takes care of that purpose) to try eeking another quarter or perhaps half volt out of the panels, either.
And of course last, the weather gods still won't whisper in my ear and let me know when there will be a nice clear sunny late afternoon to finish some testing.