Update: April 2...

Now uni is finished for semester and everything's quieting down I finally have enough brainspace to do an update post.
Tinkering continues. I managed to be in the right place to catch when a couple of 250w panels fell off the back of a truck, so there's now ~320w of power available (I'll spare you the essay, but PWM voltage modulation is ridiculously lossy if you don't get the right input voltage). A drop in at Battery Wizards Welshpool yielded 3 more ~90 Ah batteries, 2 of which (Hardy and Strong) have passed testing and cycled into use. Bombadil is showing massive voltage drop under load and may have been cooked, but is getting a test to see if he still has life or if it was a wiring problem.
On the topic of wiring, I ran an experiment in balance charging that looked positive, and some reading showed I was on the right track so Tom has now been completely rewired to give me better battery management and even loading across the cells.
At the moment I'm able to draw 200w of power through the AC inverter plus another 50w of unaltered DC, all without showing voltage drop below Float level, when the panels are energised. Testing done after dark yielded ~0.5kWh of sustained drain without dropping the stack below 12v using only Hiddleston, Bombadil and Hardy, so there's more to give now Morello and Strong have been sub'd in. Battery performance imbalance was what gave me the idea for charge/load balancing. Now that's done I'm going to look at connecting some serious load and seeing what it can really do...




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