eric@null.uucp (Eric J. Johnson) (11/17/89)
I am looking for a true UPS (zero switchover time) that will provide about 10A 115V for 15-30 minutes. Does anyone have any suggestions? I have tried using a less expensive standby power system (2-4 millisecond switchover) but that seems too long a delay (or too low a voltage) for my equipment. Thanks. -- Eric J. Johnson UUCP: eric@null.uucp The opinions expressed in this article are those of the author and in no way reflect the will of Landru. (or U S WEST Communications)
shepperd@dms.UUCP (Dave Shepperd) (11/21/89)
From article <1989Nov17.140437.13421@null.uucp>, by eric@null.uucp (Eric J. Johnson): > > I am looking for a true UPS (zero switchover time) that will provide > about 10A 115V for 15-30 minutes. Does anyone have any suggestions? I I suggest you use a Best Power System. Their 1.5KVA unit is $2,895 (a bit pricey). You can reach them at (800) 356-5794 or (608) 565-7200 in Wis. -- Dave Shepperd. shepperd@dms.UUCP or motcsd!dms!shepperd Atari Games Corporation, 675 Sycamore Drive, Milpitas CA 95035. Nobody knows what I'm saying. I don't even know what I'm saying.
davidc@vlsisj.VLSI.COM (David Chapman) (11/21/89)
In article <1989Nov17.140437.13421@null.uucp> eric@null.UUCP (Eric J. Johnson) writes: > I am looking for a true UPS (zero switchover time) that will provide >about 10A 115V for 15-30 minutes. Does anyone have any suggestions? I >have tried using a less expensive standby power system (2-4 millisecond >switchover) but that seems too long a delay (or too low a voltage) for >my equipment. Thanks. The best way to get zero switchover time is to buy a UPS that supplies power from a DC-AC inverter running off of a battery. The battery is then charged by an AC-DC power supply. This is the way our UPS runs; it has about 10 VAX minicomputers and 150 workstations hanging off the back. Of course, it has a room full of batteries too. :-) I don't know any model names, unfortunately, but you should be able to find out whether a particular model is set up this way. It's important enough that it has started to become a sales point. -- David Chapman {known world}!decwrl!vlsisj!fndry!davidc vlsisj!fndry!davidc@decwrl.dec.com
rbc@cbnewsh.ATT.COM (robert.connaghan) (11/22/89)
AT&T makes a series of UPS's with zero crossover time. They come in 1, 3, 5, and 10 KVA flavors. Call 1-800-372-2447 for more info. They filter and regulate the incomming AC to your load, provide surge protection, and have no minimum load. The battery backup system runs in parallel to this in stand-by mode until the AC input is gone or just out of spec (brown-out) and then the battery provides power to a DC-to-AC converter that is switched in "transparently to the load" (I'm reading from the brochure). They can be upgraded with additonal batteries. 1KVA with internal batteries, 10 Min, 60 min with external batteries. 3KVA with internal batteries, 12 Min at full load. Robert Connaghan AT&T Bell Labs Holmdel, NJ 201-949-1048 vax135!rbc
macy@fmsystm.UUCP (Macy Hallock) (11/22/89)
In article <897@dms.UUCP> shepperd@dms.UUCP (Dave Shepperd) writes: >From article <1989Nov17.140437.13421@null.uucp>, by eric@null.uucp (Eric J. Johnson): >> >> I am looking for a true UPS (zero switchover time) that will provide >> about 10A 115V for 15-30 minutes. Does anyone have any suggestions? I > >I suggest you use a Best Power System. Their 1.5KVA unit is $2,895 (a bit >pricey). You can reach them at (800) 356-5794 or (608) 565-7200 in Wis. You may also wish to look at products from American Power Conversion. We use their products behind the computer and phone systems we sell. Rather that counsel you on the net, since I know not your application... give them a call at 1-800-443-4519. Assuming their AP1500 is the correct unit for you application (1.5KVA with battery, for small minis, micro VAXen and such...), lists for $3195.00. Available from most distributors for $2200 to $2400 (see Computer Shopper, PC Week, PC Magazine, APC dealers regularly advertise in these publications) Macy M. Hallock, Jr. macy@NCoast.ORG uunet!aablue!fmsystm!macy F M Systems, Inc. {uunet!backbone}!cwjcc.cwru.edu!ncoast!fmsystm!macy 150 Highland Drive Voice: +1 216 723-3000 Ext 251 Fax: +1 216 723-3223 Medina, Ohio 44256 USA Cleveland:273-3000 Akron:239-4994 (Dial 251 at tone) (Insert favorite disclaimer here) (What if I gave a .sig and nobody cared?)
kaufman@Neon.Stanford.EDU (Marc T. Kaufman) (11/23/89)
In article <15396@vlsisj.VLSI.COM> davidc@vlsisj.UUCP (David Chapman) writes: >The best way to get zero switchover time is to buy a UPS that supplies power >from a DC-AC inverter running off of a battery. The battery is then charged >by an AC-DC power supply. This is the way our UPS runs; it has about 10 VAX >minicomputers and 150 workstations hanging off the back. Of course, it has >a room full of batteries too. :-) Best Power (address previously posted by someone) uses a Ferro-Resonant isolation transformer with a third winding for the inverter. There is enough stored energy in the transformer that the inverter can remain off until the main power quits, then turn on to provide backup power. A couple of side benefits are that the battery derived power is sine-wave, and the mains power is cleaned up a lot by the transformer. They cost about 150%-200% of a TrippLite, however. Marc Kaufman (kaufman@Neon.stanford.edu)