UPS's are available in various levels of intelegence and brawn. The most intelegent are know as "Smart UPS's", which use ascii protocols to communicate such information as expected battery life, internal temperature, serial number, and, by the way, the power has just failed.
"Dumb" UPS's use the serial control lines (DTR, RTS, CD, CTS, DSR, etc.) to inform the computer that the power has failed, that the battery is low, and to allow the computer to turn off the UPS's inverter.
The remaining UPS's might be called "Autistic", as they don't tell the computer anything. Apparently they depend on the operator noticing that it is dark (except for the glow of the monitor), and shut the system down manually.
A recent trip to the local computer stores revealed UPS's from APC, Belkin, MinuteMan, SL Waber, and TrippLite. These ranged from an autistic, 250VA model for about $100.00 to a 700VA smart 'network' model for almost $600.00. It does pay to shop around, as I saw a 20% price variation in one model.
Most UPS's look a lot like bricks, and are apparently intended to sit on the floor next to the wall outlet. There is, however, a kind of UPS that looks a lot like a power controller, and is intended to sit under the monitor. The SL Waber UPStart, for example, has switches to control the monitor, a printer, and a couple of 'aux' outlets. Only two outlets are UPS protected, the printer and aux outlets are unprotected, so as to save the battery power for important stuff, like the computer and disk drives, leaving the power hungry laser printer in the cold (so to speak).
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Last Modified: Wednesday, October 10, 1996
Ben Spade /
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