keithl wrote: ... > to the new optical network terminal ... about the size > of a large paperback book, and powered by a 12V/2A > wallwart (wallwart wire down the preexisting cable > tray, cat5e cable using the same armored tray). ...
Good news! The Ziply optical network terminal is actually a smaller device, 5.5x5.3x1 inch, snapped to the front of a 1 inch deep tray. The tray behind holds a few loops of fiber optic cable ... taking up slack in the feed from the street. Note that in my case, I have a crapton of fiber slack, left over from the prior Verizon ONT install. So there is a large separate box to the side, with about 20 more big loops of fiber optic. ( Perhaps they were thinking (?!) we would build a new house someday, farther back on our 300 foot deep lot. ) Below the ONT is a cover for cabling and connectors which SNAPS DOWNWARDS to reveal, among other things, a standard connector to the generic 12V wall wart. THIS CHANGES EVERYTHING. The devices that will be associated with the Ziply ONT: 1) A PC Engines APU firewall computer 2) An access point for PersonalTelco public wifi 3) A 5 port gigabit switch 4) The Ziply optical network terminal itself ALL run on some approximation of 12V DC. Yay! For testing purposes, I can power each device with a lab bench power supply, and measure its "amps versus voltage", estimating the range of voltages near 12V DC that each device can safely endure, Just In Case. Then choose a regulated voltage range that all devices can work with, all devices fed nominal 12V in parallel. A charged LiFePO4 battery is 12.8V; a group of /charging/ batteries will likely need more, especially at end-of-life. I can power all four devices with regulated 12V±0.2V from a 12.8V bus, using low-dropout voltage regulator components. I can build an array of 12.8V LiFePO4 batteries, connected to an array power FET switches that connect one of those batteries to the group of computer devices (through a low-drop regulator), and the rest of the batteries to float charging circuits. If I was Arduino adept, I could use that to manage all the batteries, perhaps performing "impedance tests" on the batteries and sending emails to me if one of the LiFePO4 batteries is wearing out and needs replacing. I can imagine scaling this to shared power and control buses attached to WEEKS worth of LiFePO4 batteries, a scalable solution that ubergeek hobbyists would enjoy building and deploying. I am not an Arduino adept, but someone reading this might be. I can design the power electronics and describe the controller behavior. Perhaps someone reading this can program an Arduino controller for it, then build a business supplying expandable 12V UPS systems. At age 70, I don't need another hobby, nor another startup, but one of you might enjoy the challenge. ---- A rich showoff might enjoy owning an array of 50,000 long-life LiFePO4 batteries, powering their 12V devices for decades, until THEY are 70yo. MANY competitive rich showoffs (100,000 batteries! 1,000,000!) could make the geek supplying them a rich showoff as well. Greener than private jets and giant yachts and bitcoin mining farms. Just sayin' ... :-) ---- Keith L. -- Keith Lofstrom kei...@keithl.com
