One thing I've found is that it would do me well to tighten up on how the big laptop gets its power... Its my big offender by far and running it via inverter/power brick is proving to be a little much... Depending on what its doing, it doesn't leave much margin for charging the main bank.
I have a boost converter that is relatively efficient that I'm going to try out in place of running the inverter/brick combo, should help.
Does the big laptop have the internal battery, and in decent working condition?
(or could you build a battery for it?)
Sounds like something a "ghurd timer" could help with.
Dump load goes high, meaning batteries are about full, timer turns the laptop charger on for a short time, resets every time the dump load pulses (without the off time to reset), power that would be dumped is stored in the laptop battery.
The controller will still control the battery. The timer just uses some of the power that would have been sent to the dump load.
Small inverter with a rocker power switch, relay contacts bypass the switch, timer turns on the relay, which turns on the inverter.
Or relay in the 12V line to the boost converter.
Either way, it would automatically save power that would otherwise be lost. And that reduces power that would have come from the house bank in the evening.
If you make one, can still do a small inverter for stuff I imagine you use. Cell phone, rechargable shaver / flashlight / drill / camera / AAs / etc.
Links; One less techie, other with the techie detail stuff.
FYI- I have all the parts here, even relays and sockets, just not packaged into kits yet.
Gimme a break! I've been busy. LOL
Ugh... This one got away from me. Read your reply not long after you posted it, but didn't have time at the moment to respond, forgot to mark it unread, and well...
Unfortunately there are some "compatibility" issues with the two types of systems that, while not impossible to get around, might be impractical in the grand scheme of things.
While I'm using one of your controllers in the system, it only engages during equalization to help the MPPT bring the bank closer to 15.5 sooner. It backs off too soon otherwise. The MPPT was given the task of regulating charge voltage for normal day to day charge cycles, so while not impossible, initiating a timer and such may be difficult to implement.
Another issue is that yes, while the battery in the laptop is good, it will only run it for around an hour, and less typically for what I use it for these days, video and music. That's long enough to say its there, but not long enough to say much else. Its been a point of contention for me for a while now, but there's little I can do about it ATM.
Sad part is, the small laptop with the mega battery sits in the drawer collecting dust while all of this is going on simply because the screen is so small. I've considered making the compromise and switching them out and just accepting the smaller screen. Might happen just yet. Thing there tho is, fully loaded (wifi, full bright, running YouTube, and charging the battery all at once), the power requirements don't break the 30W mark, and my electron woes would instantly go away, probably even in winter. But I'm such a sucker for the screen with ~3.5x the real estate.
I did get the boost converter wired in, and there are some savings, but they're marginal and difficult to see just yet. I'll be doing some side by side comparisons with the boost vs inverter/brick to try and get some more concrete numbers. Computers are tricky to gather consumption info on, as the usage can vary widely depending on what they're doing.
Another thing that doesn't help is the idea that in order to get wifi, I had to resort to hacking an old Linksys WRT54GS to use it as a wifi "card". On average, its pulling between 3 and 4 watts in and of itself. The sound system uses a little more quiescent current than I wish it did too, amounting to about 4W in and of itself. Just how it is.
For the moment, I've shrunk all I can and still use the big laptop, so I've turned my attention to optimizing production. I've got an experimental yet simple method for prioritizing the aux SLA charging on the aux panel, and then snatching up what's left to boost the charge current into the main bank. Currently it's only good for another 15W, but I intend to utilize the trick from the "pseudo MPPT" from days gone by to bump that up a touch if I can. Even as is, it made a big difference today, so I'm optimistic of what yet another buck converter might be able to bring to the table. Time will tell.
If I end up succumbing to the screen and just going with the smaller laptop, the timer idea might be well worth the trouble... Charging lithium ion is more efficient than charging lead acid any day, and since I'm naturally nocturnal, I need all the help I can get LOL
I'm still unplugged, and hit a good long soaker float today, so all in all, it's working