Inverter? I barely know 'er! aka aka Frank Inverter, the sweet trans-former

 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 in series, which conveniently means it's designed around a 24v battery supply. It will also charge the batteries off an AC input, but I don't need no stinkin' AC input. A bit of modding later and the internal battery cables had been re-routed to connect to the C14 socket in the rear (for neatness) and a surplus UK power cable cut and spliced into Tom II's output. Hello, ghetto inverter!

Neat solution. Shame it sucked. Problem was it's inefficient. Compared to the Victron it pulled 20-30W just sitting still and closer to 50W whilst in use, not to mention being noisy and occasionally deciding it wanted a rest. Lesson here kids: don't use a UPS unless you have real power quality concerns. Just the idle consumption is like leaving a couple of lights on 24/7.

So I bit the bullet and ordered a 24v version of my little blue Victron second hand on fleaBay. This bastard has now been stripped for components and cables, ready to go to the local metal recyclers. I'm already working out what to do with the old one. I may have an idea...





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