You might remember that I have 3 power-related please: Tom II, plus Dick Grayson and Harry Hart which I rarely talk about. Today I want to introduce Dick. While Tom has been the dumping ground of much of my time, Dick is where I actually started, to wit, seeing what I could do with used Lithium Polymer cells (or LiPo for short). These proved far more complicated than I'd expected, and needed a lot more care and planning that I'd expected, so it's been slow going and progress has been glacial so for most people it's kinda boring. Thing is, LiPo is a pretty exciting tech. It's high-density so you can pack a lot of juice into a small space, and it can respond to peaks in load demand much, much faster than Lead Acid. Problem is they have this habit of catching fire and exploding if you mistreat them so they're not for the faint of heart, or those who are uncomfortable at the thought of asbestos underwear. The complexity comes from making sure they stay in their sa...
A couple of weeks ago Tom II got upgraded from 12v go 24v. While 12v is easier to deal with, not to mention more compatible with components, I needed to move to the higher voltage for efficiency, as well as keeping my wiring size smaller. The problem was that the little blue inverter I use for AC supply would only take a 12v input. Some gear will happily accept a range of voltages. I have some Car Accessory USB adapter's that will take 12-24v. I have some USB circuit boards for Dick that will accept 6-32v, which is pretty cool. Inverters are pretty sensitive, and the transformers are specialised, so they're more specific. I didn't want to have to buy another inverter. They can be got cheap and from what I'm reading these can be OK, but I'm not about to trust them. They *might* be ok, or they *might* blow out my server. In the short term I wanted some breathing room, so I pulled out this old UPS I had in the salvage box. It's designed to hold 2 x 12v batteries ...
I've not done a whole lot with Tom in recent history. He's been fairly stable all-told, just requiring the occasional test-and-replace of old batteries as their zombified second-lives wind down. I've been quite relyably getting ~0.5-0.6kWh of out the rig when I need to, and my little meter indicated that I had used 26kWh over 2 or so months ($6.50 worth of juice!). The problem was that apart from recharging mobile devices and po wer banks, it's quite difficult to actually use the power because the messy, leaky batteries really need to be outside, and running cables to the rig just wasn't going to be worth the cost and fuss. Anything else was going to cost money which is entirely contrary to what Project Tom Waits is all about. I had to find a way to make anything else I did cost-neutral. During my convalescence I've had some time to go through a lot of the salvage that's been tucked away, including a couple of old UPS units I'd snagged and refurbished....
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