On Thu, Aug 21, 2008 at 1:47 PM, Bill McGonigle <[EMAIL PROTECTED]> wrote: > ... must cut speaker wire!
For most of the APC Smart-UPS line, pressing the "On" button briefly will silence the "On Battery" alarm (but not the "Low Battery" alarm). For the ones with only a single "On/Off" button, I think pressing and releasing it very quickly might do it. (I recall that you need to hold it down for about 1 second to actually turn it off.) Most of the Back-UPS models are "dumb" and can't be silenced without wire-cutters. > I'm curious how noisy of an inverter APC puts in those things. Electrical or audible noise? In my experience, audible varies from unit to unit; the manufacturing criteria, if any, must be fairly forgiving. For electrical: The Smart-UPS product line is supposed to output a "pure sine" wave. I haven't verified this myself, but I'd be surprised if they were getting away with a lie on that front. Most of the Back-UPS models use a step wave approximation that's nominally "good enough" for most things. > I'm also now curious about using a bigger battery with the COTS UPS > since they've already done most of the work for me. If the battery is already charged, I think that would generally work. The only potential problem I can see would be that the DC->AC electronics might start to overheat in an extended run. A meltdown with that kind of battery amperage has the potential to be seriously dangerous. This isn't idle speculation, either. One of the rack-mount APC Smart-UPS models, the XL variant took up more rack space, and that was supposedly solely for heat dissipation reasons. > they've done most of the hard engineering work I'd be unlikely to > replicate. Hmmmm.... good point. While 12 VDC -> 19 VDC might be more efficient than 12 VDC -> 120 VAC -> 19 VDC in theory, the UPS industry has put way more engineering into the former problem than we can with the latter. -- Ben _______________________________________________ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
