Monster Media 1994 #2

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Path: bloom-beacon.mit.edu!grapevine.lcs.mit.edu!olivea!spool.mu.edu!howland.reston.ans.net!usc!elroy.jpl.nasa.gov!netline-fddi.jpl.nasa.gov!phoebe.jpl.nasa.gov!root From: ups@navigator.jpl.nasa.gov Newsgroups: comp.misc,comp.sys.hardware.hp,comp.sys.hardware.sun,comp.sys.hardware.sgi,comp.sys.hardware.next,comp.sys.hardware.ibm,comp.sys.dec,comp.unix.admin,comp.answers,news.answers Subject: Uninterruptible Power Source FAQ Followup-To: comp.misc Date: 10 Apr 1994 09:07:54 GMT Organization: Jet Propulsion Laboratory, Pasadena, CA Lines: 784 Approved: news-answers-request@MIT.Edu Distribution: world Message-ID: <2o8fla$b0s@phoebe.jpl.nasa.gov> Reply-To: npc@minotaur.jpl.nasa.gov NNTP-Posting-Host: navigator.jpl.nasa.gov Summary: Answers to FAQs about Uninteruptable Power Sources (UPS) Originator: root@navigator.jpl.nasa.gov Xref: bloom-beacon.mit.edu comp.misc:6994 comp.sys.dec:11511 comp.unix.admin:12899 comp.answers:4841 news.answers:17864 Archive-name: UPS-faq Version: 1.3 Uninteruptable Power Source (UPS) FAQ. VERSION 1.3, March 17, 1994 Sections: 01: What is this document all about? 01: What is this document? 02: How is this document made available? 03: Who maintains this? 04: Where did this information come from? 05: How can I contribute? 06: How may this document be distributed? 07: Got anything else you'd like to add? 02: What is a UPS and how does is work? 01: What is a UPS? 02: How do you pronounce "UPS"? 03: Vendor X says that (description) is a UPS, is it? 04: Describe the types of UPS's? 05: How can a UPS help me? 06: What sort of stuff does a UPS do? 07: How long can equipment on a UPS keep running? 08: What is a "good" UPS? 09: Support contracts on UPS's. 10: Self maintenance tips. 11: Is a UPS a glorified power strip? 03: UPS monitoring/shutdown software. 01: Can a UPS shut the computer down when power is low? 02: Can I write my own shutdown routines? 03: What freely distributable solutions are there? 04: No UPS software works on my machines, what to do? 04: How big a UPS do I need? 01: How are UPS sizes determined? 02: What VA rating do I need? 03: How do I determine this? 04: What else should I consider? 05: Can I use an UPS with a laser printer? 06: What UPS sizes do you use on what equipment? 05: Specific manufacturer's info. 01: What vendors are there? 06: Acknowledgments ----------------------------- 01: TOPIC: What is this document all about? 01.01 Q: What is this document? A: This is a prototype for a FAQ document on Uninteruptable Power Sources. It is intended to provide a starting point for those people that want to find out what they are, what they do, and what's available. 01.02 Q: How is this document made available? A: Well, this isn't in stone yet. Currently, its "home" is comp.misc. It is also crossposted to comp.unix.admin, comp.sys.sun.hardware, comp.sys.hp.hardware, comp.sys.sgi.hardware, comp.sys.next.hardware, comp.sys.ibm.hardware, comp.sys.dec, comp.answers and news.answers. This posting is automated and will occur on or near the 10th of each month. It probably ought to be posted to other groups as well, but I don't know which ones. If I post it to every group where UPS questions get asked, that would be a lot of groups. I'm open to suggestions. This document is also available via anonymous FTP. The master sits on navigator.jpl.nasa.gov (128.149.23.82) in pub/doc/faq as the file UPS.faq. It will probably be mirrored on other machines and contributed to rtfm.mit.edu. 01.03 Q: Who maintains this? A: Right now, this document is maintained by Nick Christenson. My preferred email address is npc@minotaur.jpl.nasa.gov, and I would like it very much if questions regarding this document could have the word "UPS or UPS FAQ" or some such in the Subject line. Note: I am maintaining this on my own time, so please don't be upset if it takes a while for me to respond to your queries. Also none of the information in here represents the views or has the blessing of any organization whatsoever. The maintainer of the FAQ is to be held solely responsible for its contents. 01.04 Q: Where did this information come from? A: Thankfully, several people have rallied to my cry to fill in the many gaps in my original draft. This is now the work of many people, although I claim full responsibility for misstatements and inaccuracies. 01.05 Q: How can I contribute? A: You should mail new information, corrections, suggestions, etc. to the current maintainer of this FAQ. If you provide a suggestion, make sure you reference where the information is located in the document. I guarantee that suggestions of the form "Change the word 'always' to 'almost always' in the part about surge suppression." will be ignored. 01.06 Q: Are there any restrictions on distribution of this document? A: This document is copyright by the author. You are encouraged to distribute this document for any non-commercial purpose as long as the contents remain unchanged. 01.07 Q: Got anything else you'd like to add? A: Yes, now that you mention it. The people who contribute to this document can speak only about equipment they have experience with. This may reflect a bias toward or against certain brands, features, functions, etc.. Please keep in mind that the suggestions, brand names and functions here are by no means exhaustive, or even necessarily applicable to your situation. Also, if you have information that is not in this document, please submit it to the maintainer listed above. If you submit information, please say whether you'd like it to be attributed to you or not. I am more than glad to give credit to the fine people who helped with this document, but I want to respect the anonymity of those people who would prefer it. 02: TOPIC: What is a UPS and how does it work? 02.01 Q: What is a UPS? A: An Uninteruptable Power Source is a device that sits between a power supply (e.g. a wall outlet) and a device (e.g. a computer) to prevent power outages from the supply from affecting the device. 02.02 Q: How do you pronounce "UPS"? A: I pronounce it "ups", but most of the literature seems to favor "you pee ess", since they use "a UPS" instead of "an UPS". This document will try to follow the literature. 02.03 Q: Vendor X says that (fill in description) is a UPS, but it's different that what you describe above. Who's right? A: There really is no standard definition of what a UPS is. Anything ranging from a 9 volt battery backup in a clock radio to a building/compound wide backup generator has been called a UPS by someone. The majority of this document refers to objects larger than a beer can and smaller than a desk that help devices remain functional when changes to the power they receive would otherwise interrupt their function. Maintaining power to a minicomputer (like a VAX 11) is beyond the scope of this document. This FAQ deals with UPS equipment that can be installed by a computer owner/administrator If you have requirements that large, you need to talk to a qualified electrician. 02.04 Q: Can you give me some more information on this? A: (Kindly provided by Don Deal, Don.Deal@oit.gatech.edu) The UPS industry is made up of many manufacturers, and there is a lack of standard terms within the industry. I think this sometimes borders on deliberate misdirection. (It's a jungle out there!) There are basically three different types of devices, all of which are occasionally passed off as UPSs. 1. Standby power supply (SPS). In this type of supply, power is usually derived from directly from the power line, until power fails. After power failure, a battery powered inverter turns on to continue supplying power. Batteries are charged, as necessary, when line power is available. This type of supply is sometimes called an "offline" UPS. The quality and effectiveness of this class of devices varies considerably; however, they are generally quite a bit cheaper than "true" UPSs. The time required for the inverter to come online, typically called the switchover time, varies by unit. While some computers may be able to tolerate long switchover times, your mileage may vary. Other features to look for in this class of supplies is line filtering and/or other line conditioners. Since appliances connected to the supply are basically connected directly from the power line, SPSs provide relatively poor protection from line noise, frequency variations, line spikes, and brownouts. 2. Hybrid UPS systems. I only know one vendor who sells them - Best Power, Inc. The theory behind these devices is fairly simple. When normal operating line power is present, the supply conditions power using a ferroresonant transformer. This transformer maintains a constant output voltage even with a varying input voltage and provides good protection against line noise. The transformer also maintains output on its secondary briefly when a total outage occurs. Best claims that their inverter then goes online so quickly that it is operating without any interruption in power. Other UPS vendors maintain that the transition is less than seamless, but then again it's not in their best interest to promote Best's products. Best has a sizable part of the UPS market. [ Note: According to some sources, ferroresonant transformers in an UPS system can interact with ferroresonant transformers in your equipment and produce unexpected results. The Moral: Again, test before you buy. -npc ] 3. What I call "true" UPS systems, those supplies that continuously operate from an inverter. Obviously, there is no switchover time, and these supplies generally provide the best isolation from power line problems. The disadvantages to these devices are increased cost, increased power consumption, and increased heat generation. Despite the fact that the inverter in a "true" UPS is always on, the reliability of such units does not seem to be affected. In fact, we have seen more failures in cheaper SPS units. 02.05 Q: How can it help me? A: An UPS has internal batteries to guarantee that continuous power is provided to the equipment even if the power supply stops providing power. Of course the UPS can provide power for a while, typically a few minutes, but that is often enough to ride out power company glitches or short outages. Advantages: 1) Computer jobs don't stop because the power fails. 2) Users not inconvenienced by computer shutting down. 3) Equipment does not incur the stress of another (hard) power cycle. 4) Data isn't lost because a machine shut down without doing a "sync" or equivalent to flush cached or real time data. 02.06 Q: What sort of stuff does a UPS do? A: An UPS traditionally can perform the following functions: 1) Absorb relatively small power surges. 2) Smooth out noisy power sources. 3) Continue to provide power to equipment during line sags. 4) Provide power for some time after a blackout has occurred. In addition, some UPS or UPS/software combinations provide the following functions: 1) Automatic shutdown of equipment during long power outages. 2) Monitoring and logging of the status of the power supply. 3) Display the Voltage/Current draw of the equipment. 4) Restart equipment after a long power outage. 5) Display the voltage currently on the Line. 6) Provide alarms on certain error conditions. 7) Provide short circuit protection. 02.07 Q: How long can equipment on a UPS keep running after the power goes? A: How big a UPS do you have and what kind of equipment does it protect? For most typical computer workstations, one might have a UPS that was rated to keep the machine alive through a 15 minute power loss. If you need a machine to survive hours without power should probably look at a more powerful power backup solution. Even if a UPS has a very small load, it must still operate it's DC (batter) to AC converter, which costs power. A rough extrapolation from APC's documentation, leads me to guess that a 2000 VA UPS can operate it's own converter (with no extra load) for just over 8 hours. A 1250 VA UPS could run its converter for about 5. These are *very* rough guesses based on information provided by one vendor for one vendor. 2.08 Q: Given the same vendor claims, how can I tell a "good" quality UPS from a "poor" quality UPS? A: Testing, testing, testing. I can't emphasize this enough. There are many good and bad units out there that call themselves UPS's. Caveat Emptor. Some properties you might look for are: 1) Sinusoidal power output. In general, the closer the AC output of the UPS is to a sine wave, the better it is for your equipment. Many UPS units, especially the cheaper ones, deviate a great deal from a sinusoidal output. Some of them generate square waves. Don't buy these, period, they can cause serious damage to your equipment. 2) Does the UPS have a manual bypass switch? If the UPS is broken or is being serviced, can you pass power through it to your equipment? The last thing you want is for a broken UPS to be the cause of extra downtime. 3) The more information about a UPS's operation you can get from watching the unit itself, the better. How much power (or percentage load) the equipment is drawing, how much battery life is left and indications of the input power quality are all very useful. 4) Some newer UPS's can communicate with their monitoring software via network connection and SNMP! This is wonderful *if* your network is on a UPS! Also, beware, I have heard of dealers advertising "Network UPS" monitoring where the network is the normal serial connection (no SLIP or PPP). 5) Does the UPS vendor offer support/maintenance contracts. If they don't even offer them, I would suspect the quality of the equipment. If you do have a UPS that does not output a sinusoidal waveform, some manufacturers *strongly* urge you to not put a surge protector between the UPS and the computer. The surge protector may mistake the non-sine waveform as a power surge and try to send it to ground. This could be bad for your UPS. I don't know if this is really true or not. 02.09 Q: Should I make sure I have a support/maintenance contract for my UPS systems? A: Some people strongly recommend this, but to be honest, I don't know how important it is. I haven't had any UPS's long enough to have enough of them fail to know what the failure modes are likely to be. Some people, with more experience than I in these matters, insist that a UPS support/maintenance contract is as important as your computer support/maintenance contract. I can't argue with them. In any case, it's almost certainly worth pricing at any rate. 02.10 Q: What sort of maintenance can I perform myself? A: One good thing you might want to do is periodically test the UPS's and their failure modes. A good time to do this might be right after after a periodic level 0 backup. Nobody is logged in and you've got full backups of the machines. Pull the plug on the UPS to simulate and outage and see how the transition goes. Those UPS units that use lead-acid batteries (that's most of them, I'm told) do not have a battery memory and should be run dry as few times as possible. It's probably not a bad investment to do this once on one UPS to learn how much UPS time you can expect in a real power outage. Note, depending on the manufacturer, UPS batters can be expected to last between about 1 and 5 years before they need to be replaced. 02.11 Q: Isn't a UPS just a glorified power strip/surge protector with some batteries and a little power conditioning thrown in? A: Basically. It's also got a power inverter and some other circuitry. It may also have a timer, thermometer or other gadgets. 03: TOPIC: UPS monitoring/shutdown software. 03.01 Q: If the power is out for a long time, I would like to have my computer automatically shut itself down gracefully before the UPS batteries die. Can I do this? A: Yes. Most UPS manufacturers support software that will do this for some UPS's on at least some platforms. Ask your UPS vendor for details. 03.02 Q: How does it work, I'm a starving (fill in the blank) and I really don't want to pay for software unless I absolutely have to. A: Usually, there is a serial connection running from a UPS into your computer. The UPS sends information along the serial line as it goes. If you can decode which pins contain which information, how the information is formatted and figure out what it wants to hear from the computer side, you're all set. Since UPS units with network based monitoring capabilities are appearing on the market, we can hopefully get something that will communicate with those units. Here is a skeleton script provided by Joe Moss, joe@morton.rain.com. Definitely check this out as a starting point, but don't expect it to do anything meaningful without some work. ---------start upsd.sh------------- #! /bin/sh # Shut down system in case of extended power failure # This should be the serial port to which the UPS is connected # This port must be set to block on open until the DCD line # is asserted - many UNIX systems have this determined by # the minor device number, if not, see if there is some way # to enable this behavior on your system PORT=/dev/ttya # Ok, this should block until there is a power failure : > $PORT # If we reach this point, we've lost power wall << EOF The sky is falling!! The sky is falling!! EOF # call shutdown (or init or whatever) exec shutdown -----------end-------------------- 03.03 Q: Hmmm... that sounds kinda complicated. Has someone already done this? A: Any solution would almost certainly be vendor specific. However, some brave souls have provided partial functionality for certain vendors' UPS's. I don't know the original source, but I have a copy available for anonymous FTP at navigator.jpl.nasa.gov in the pub/src/upsd directory. I haven't tried it and I don't honestly know if it even works. Note: Different UPS's produce different sorts of signals. Just installing this already built package may require a great deal of work. The cabling can be complicated, etc.. I would be interested in hearing where this software does/doesn't work. 03.04 Q: I can't find monitoring software that will work on my configuration. What should I do? A: Well, it seems you have a few choices: 1) Build your own. See item 03.02. 2) Use something freely distributable. See item 03.03. 3) Lean on your UPS vendor to port to your platform. 4) Try a different vendor that supports your platform. See item 05.01. 04: TOPIC: How big a UPS do I need? 04.01 Q: How are the "sizes" of UPS's determined? A: Typically, a UPS has a VA rating. The VA rating is the maximum number of Volts X Amps it can deliver. The VA rating is not the same as the power drain (in Watts) of the equipment. Computers are notoriously non-resistive. A typical PF (power factor: Watts/VA) for workstations may be as low as 0.6, which means that if you record a drain of 100 Watts, you need a UPS with a VA rating of 167. WARNING: Don't take my word for it. Note: Some UPS's can continue to deliver power if the VA rating is exceeded, they merely can't provide above their VA rating if the power goes. Some can't provide power above their VA rating at all. Some may do something really nasty if you try. In any case, I *strongly* recommend not doing this under *any* circumstances. 04.02 Q: How can I tell what VA rating I need for my equipment? A: First, when possible, get VA rather than wattage ratings. See Q04.01 above. There are a couple of ways: 1) Direct measurement. You can get equipment to measure the current draw of your equipment directly. You may or may not have access to this. If you are part of an organization that has it's own facilities/electrical type people, they're likely to be able to do this. They might help you out if you ask nice. 2) Compare notes. If you know someone with the same setup you're using, ask them what they use and how close they are to the maximum VA rating. 3) Use a chart. Most vendors can help you out for common equipment. If you have an unusual setup, or a mix vendors a lot, you're probably out of luck here. 4) Use the equipment rating. Most pieces of computer equipment have a power rating on some back panel. This number is usually high, as it is necessary for the manufacturer to play it safe or they'll get sued. Note: Method 1 is by far the best, method 2 and 3 are secondary, method 4 is usually overkill, but pretty safe. 04.03 Q: Hmmm... seems like a tough thing to determine. A: Yeah, it can be. It's also very important. If you get a UPS that's too big, then your equipment can survive a longer outage. If you get a UPS that's too small, then you could be in deep trouble. Therefore, I recommend that you be conservative in buying these things, unfortunately, this costs money. 04.04 Q: What else should I consider? A: It would be nice to know how long your site's typical power outages are. In some places, with nice weather and a flakey power grid, the power is almost never out for more than 5 minutes, but this could happen quite frequently. In this case, you may as well use a UPS with a VA rating close to your equipment rating with no extra batteries. If your area has longer outages, in the half hour or hour range, as is often the case in thunderstorm country, you can either buy UPS's with multiples of the VA rating of the equipment, since oversizing a VA rating for a UPS has the effect of lengthening the amount of time your equipment can stay up in case of a power outage, or you can buy additional battery units for a smaller UPS. You can probably get away with doing simple math to determine how much longer a larger UPS will keep your equipment running, but I recommend running a few tests before committing to a large purchase order. Also, your UPS vendor will almost certainly be glad to help you size the equipment you need. If all else fails and you guess wrong, or move equipment to a location with different power status, you may be really, really glad if you bought a UPS that can have additional battery packs added. 04.05 Q: How about I use one of these UPS thingies for a laser printer? A: Don't *ever* do this. If you ever measured the current draw of a laser printer during startup (and during printing) you'd be stunned at what it pulls. All UPS manufacturers I know of tell you not to do this. 04.06 Q: So, what sorts of UPS sizes do you use on your equipment? A: BIG DISCLAIMER. I disclaim everything about these figures. I may be lying. Don't trust them. Here they are anyway. 400 VA: Sparc 2 with 3 600 MB disks, 1 200 MB disk, 1 exabyte 8200 tape drive, 19" color monitor. 600 VA: HP 750 with 4 1.3 GB disks, internal 4mm tape drive and internal CD-ROM drive, external disk cabinet and 19" color monitor. 500 VA: SPARC 2GX clone. 1 1.2 GB disk, 4 2.0 GB disks, 2 tape drives, 1 CD-ROM drive, "big" monitor. 05: TOPIC: Specific manufacturer's information. 05.01 Q: What vendors are there and what do they produce? A: Here is a very incomplete list, based only on what I know. Please give me information to expand it. I make no claims as to the accuracy of this information. It is mostly based on personal recommendations and vendor propoganda. Company: APC, American Power Conversion US Address: 132 Fairgrounds Road P.O. Box 278 West Kingston, RI 02892 FR Address: 4, rue Ste Claire Deville Zac du Mandinet-Batiment Espace LOGNES 77447 MARNE LA VALLEE Cedex 2 FRANCE US & CAN Phone: 1-800-800-4272 Europe Phone: (+33) 1.64.62.59.00 World Wide Phone: (401) 789-5735 Email: none known UPS Products: Smart UPS in sizes up to 2000 VA. The Smart UPS's do monitoring and can shutdown multiple machines using the PowerChute software. I recommend putting these on computers. SNMP adaptor can be installed. Back UPS same as Smart UPS except that you cannot communicate interactively with the UPS and it will not support SNMP. I recommend putting these on dumb equipment like network equipment, X Terminals and Macintoshes (sorry, I couldn't resist.) Matrix UPS a modular "fault-tolerant" system. Any module, except the insulation unit, can be "hot-swapped" at any time. Also additional battery modules can be added, again, while the system is running. SNMP adaptor can be installed. Software: PowerChute, PowerChute PLUS. They produce it themselves. Supported on: SunOS, HP-UX, SCO, AIX, AT&T UNIX, Interactive UNIX, XENIX, and probably others by now. Contributed by: APC information contributed by Nick Christenson, npc@minotaur.jpl.nasa.gov without consultation with APC. Additional information provided by Joe Moss, joe@morton.rain.com. I have no affiliation with APC except as a satisfied customer. Company: Best Power Technology, Inc. P.O. Box 280 Necedah, WI 54646-9899 US Phone: 1-800-356-5794 Email: None known UPS Products: FERRUPS: Ferroresonant-Based, Line-Interactive UPS, sizes from 500 VA - 18 KVA. Features: Standard power features, serial line communications, runtime monitoring, logging, automatic shutdown with optional software, user configurable. FORTRESS: Advanced, line-Interactive UPS, sizes from 360 VA - 2 KVA. PATRIOT: Low-Cost Standby Power Systems, 250 VA - 850 VA. Contributed by: Scott Pinkerton, spinkert@t4rta-gw.den.mmc.com Company: Emerson Electric Co., Computer Power Div. US Address: 9650 Jeronimo Road Irvine, CA 92718, USA UK Address: Elgin Drive, Swindon Wiltshire SN2-6DX, England FR Address: 8, Rue de l'Esterel Silic 502 94623 Rungis Cedex France IT Address: SICE S.p.A. [Note national Name!] Via Rossini 6 20098 San Giuliano Milanese Italy US Phone: 1-800-BACKUPS UK Phone: +44 458 841898 FR Phone: +33 146 862336 EMail: n/a Products: Accupower GOLD Series: UPSes for 750, 1000, 1500, 2100 VA, the latter with external Batt Pack. Connector for {Power,Accu}Mon S/W. 5 yr Batt Life. Good Display (3 Status LEDs, Load and Batt Charge LED Bargraphs). Switches positioned wrong (Main Power Switch on Front, Batt Check/Alarm off on Back - I'ld prefer them the other Way 'round). other UPSes? PowerMon Software: Triggers for Outage, long Outage, Batt low. Uses one serial Connector. Logging and Warnings to Users. Requires special Cable (included in PowerMon Kit). NOTE: The "Batt low" Trigger does not work "on SunOS 4.1.1 and above due to OS Limitations". >:-C I don't know whether this includes Solaris 2.x. AccuMon Software: Reported to support all Kinds of fancy Communication Items (gathering Power Line and internal UPS Data, test Batt Cap periodically and announce Batt Aging, switch off UPS on Computer Command, Logging Facili- ties for all these Functions) Other Software? Contributed by: Jochen Bern, bern@kleopatra.Uni-Trier.DE who has no relation to Emerson. Company: Easy Options IBM Corporation Address: IBM Corporations Easy Options Dept. WC3J P.O. Box 2150 Atlanta, Ga 30301-9948 US Phone: Unknown. UPS Products: UPS ranging from 250 VA to 600 VA with surge and noise suppression. Sine wave output, Test/Alarm, etc.. These UPS's come with an insurance policy. If your UPS damages your systems, they'll pay you up to $25,000. Software: Works with APC's PowerChute software. I doubt that IBM is making their own UPS's rather than repackaging someone elses, but I'll be glad to post a correction if they are. Contributed by: Dave Gruhn, dgruhn@fuzzy.eskimo.com who has no relation to IBM, or Easy Options except as a satisfied customer. Company: Clary Corporation Address: Clary Corporations 320 W Clary Ave San Gabriel, CA 91776 US Phone: 818 287-6111 UPS Products: I'm not sure of the entire line, but their PC series includes UPS ranging from 400 VA to 1500 VA with surge and noise suppression. Voltage regulation to 3%, frequency to 1 Hz, RS232 signal output, LED load and charge indicators. Sine wave output, Alarm, etc.. Contributed by: Ron Tansky, ron.t@bix.com (who has no relation to Clary Corporation except as a user.) Company: Advanced Electronic Systems, Inc. 2005 Lincoln Way East Chambersburg, PA 17201 US Phone: 1-800-345-1280 Email: None known UPS Products: Stediwatt UPS: Designed specifically for use with NeXTSTEP. Contributed by: Robert D. Freeman, rdf@thermo.chem.okstate.edu Also on the NeXTSTEP front, there is a company called BenaTong (?) which sells a software package called PowerGuardian for NeXTSTEP only. It will work with APC, TrippLite and UNISON UPS's. If, for example, you call APC and ask for PowerChute for NeXT, they will refer you to Power Guardian. Contributed by: Chuck Bennett, (chuck@benatong.com) who works for this company. Company: DELTEC 2727 Kurtz St. San Diego, CA 92110-9980 US Phone: 1-800-854-2658 Email: None known UPS Products: "Most technologically advanced *true* on-line UPS." Contributed by: Robert D. Freeman, rdf@thermo.chem.okstate.edu Company: Acme Electric Corp. 43 Argow Place Nanuet, NY 10954 US Phone: 1-800-833-1373 Contributed by: Robert D. Freeman, rdf@thermo.chem.okstate.edu Company: Tripp Lite 500 N. Orleans Chicago, IL 60610-4188 US Phone: 1-312-329-1601 Email: None known UPS Products: On-line UPSs with pure Sine Wave output. Contributed by: Robert D. Freeman, rdf@thermo.chem.okstate.edu Company: Data General UPS Products: Data General repackages another vendor's UPS's (from Exide?) with some sort of special cable. They deserve some mention since they provide UPS monitoring software built in to the AViiON (their UN*X boxen) line. It can be managed through sysadm(1M). Contributed by: Morris Galloway Jr., mmgall@presby.edu Other companies: Exide Sola Electric ITT Power System Corp Digital Equipment Corporation. (They probably repackage someone else's stuff, but they're likely to support it and you can order it from their catalog.) I'd appreciate any information I can get on these. 06: TOPIC: Acknowledgements I would like to thank Charles Rhoades (cwr@zeus.jpl.nasa.gov) for his sage remarks on my draft of this document. I would like to thank Kevin R. Ray (kevin@kray.com) for sending me the freely distributable upsd software. Thanks also to Don Deal (Don.Deal@oit.gatech.edu) for a great many valuable suggestions and that great section on the types of UPS units. The following people made valuable suggestions to this document: Scott Pinkerton, spinkert@t4rta-gw.den.mmc.com Morris Galloway Jr., mmgall@presby.edu David E A Wilson, david@cs.uow.edu.au Edward Hartnett, ejh@larry.gsfc.nasa.gov Joe Moss, joe@morton.rain.com Kurt Hillig, khillig@chem.lsa.umich.edu Robert D. Freeman, rdf@thermo.chem.okstate.edu Jochen Bern, bern@kleopatra.Uni-Trier.DE Dave Gruhn, dgruhn@fuzzy.eskimo.com Steve Welch, smw@columbine.cgd.ucar.edu Ron Tansky, ron.t@bix.com Andrew J. Templin, nosilla@ohionet.org Chuck Bennett, chuck@benatong.com Please note that I take full blame for any errors or omissions. .