Quoth Neon John at 2008-05-03 08:16... > Set each one to 6 volts, hook 'em in series and use 'em to run big 12 volt > loads. I ran a homemade true uninterruptible power supply for years using > that lashup.
OK, whilst we're deviating from time a little, I would like to put a time and power supply question to my learned colleagues: I am building two GPS-driven devices, an NTP server based on an ancient single board computer and a Nixie clock. Our power here is not what one might call reliable - we are stuck on a spur of a very long 19kV, single wire, earth return supply which plays up a) when there is a thunderstorm within 200 miles and b) when it feels like it. Whilst I could incorporate mains power supplies into both units, I like to avoid getting mains in my constructions if I can avoid it. The SBC has a PC-104 automotive PSU fitted and I'm building the supplies for the Nixie clock (+5V, +12V, +170V) to operate from about 11.9V (shutdown if less) to 15V DC. My thought was to integrate a UPS component into the design by connecting these to 12V 7Ah sealed lead acid batteries, which I can get for just over $20 AUD a piece. If I were to do this, would it be sufficient to power the units from a 13.8V supply? I believe this to be within the voltage range for float-charging the batteries so was guessing that this may be a simple way to provide uninterrupted power to my gear. Cheers M -- Matthew Smith Smiffytech - Technology Consulting & Web Application Development Business: http://www.smiffytech.com/ Personal: http://www.smiffysplace.com/ LinkedIn: http://www.linkedin.com/in/smiffy _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.