maxwell@ablnc.UUCP (11/12/87)
In article <942@woton.UUCP>, riddle@woton.UUCP (Prentiss Riddle ) writes: > My resistance is weakening and I am getting closer by the day to breaking > down and buying a 3B1 for myself. (I know, if I want to do it I'd better > hurry, as supplies are running low.) One obstacle remains, though, which > may keep me from it even if my willpower doesn't: > > I live in an old house with a rather flaky power system. Even ordinary ^^^^^^^^^^^^^^^^^^ [serious] > household appliances, when used in certain combinations, have been > known to cause brownouts and occasionally throw a circuit breaker. Am ^^^^^^^^^ [dangerous] > I asking for it if I try to use a UNIX PC in this power environment? > Does anybody know of any *cheap* power conditioning which might > significantly improve my 3B1's chances of survival? Thanks. > > --- Prentiss Riddle ("Aprendiz de todo, maestro de nada.") To: codas!killer!woton!riddle Subject: Re: 3B1 and flaky power In-reply-to: your article <942@woton.UUCP> It sounds to me like you have a serious wiring problem. I would have an electrician check out your house wiring before you wake up some night smelling smoke. I am very serious about this, I have worked as an electrician and I know enough about it that I would be afraid to put anything of value (including my family) in a house with that kind of problem until I was sure the problem was in the power feed outside of the house ( a possibility). If the problem is in the feeder system to your house, contact your power company. Only after you have done what you can to correct the source of the problem should you look into covering the symptoms. -- ----------------------------------------------------------------------------- Bob Maxwell AT&T DP&CT | All standard (and most non_standard) Maitland, FL ihnp4!ablnc!maxwell | disclaimers apply. -----------------------------------------------------------------------------
riddle@woton.UUCP (11/18/87)
Last week I asked for advice about the advisability of putting a UNIX PC in my home given a rather unreliable power situation. Here are some of the reponses I received. Darryl Wagoner (dpw@unisec.usi.com, ihnp4!rayssd!unisec!dpw): >> The 3b1 has the best power supple of any computer I have seen. I have >> seen it take "blink" in power that has knock out my VCR, and every computer >> at where I use to work (which includes 11+ Vax's, 4 Suns, and a Pyramid). Brian Kantor (brian@sdcsvax.UUCP): >> The 3B1/7300 draws about the same amount of power and has the same type >> (switching inverter) of power supply as an IBM PC. These are >> relatively robust supplies, and not difficult to repair. Unless you >> regularly experience surges on your power line (lights flashing >> BRIGHTER), you probably won't have problems. >> >> If your power is really bad, you might be able to find a Sola Corp >> constant-voltage transformer in some surplus house, or buy a power >> conditioner that has one in it. They'll eat most line surges and fix >> brownouts, so they might be worth hunting up. I'll bet they're not >> cheap new. Check the Inmac catalog to find out availability; don't buy >> it from them because you can probably get it cheaper elsewhere. P. Trent MacDougall (watmath!dalcs!dalcsug!ptmcd, iisat!tmpor!trent): >> Just to tell you a little about what has happend to me. >> >> My room is in the basement of our house, and when the water pump comes >> on the lights go dim for a sec. Well I thought nothing of this. I >> hooked up my 3b1 and after about 1 week it crashed. I tried things >> again and it crashed in about another week. Needless to say I was very >> unimpressed with the situation, so I called AT&T. They couldn't tell >> me anything and wanted to swap the motherboard (what else is new :-). >> After it crashed one more time I was starting to panic (addr fault in >> kernel) myself; so while I was thinking about what to do the pump came >> on and it hit me. Sure enough, I ran a cord upstair where the 3b1 >> would be on its own circuit and it was up for 37.5 days without doing >> anything to it; it didn't crash this time but it locked up. Prob. >> this time because of the power company. >> >> So after saying all that, the 3b1 is very sensitive to fluctuations in >> power. If your machine crashes alot with `panic: addr fault in kernel' >> that could very well be your prob. Olaf I. Henjum (ihnp4!ihlpf!olaf): >> Probably your best SHORT-TERM solution will be to make a copy of your >> (10-sector-format) diagnostics floppy and make SURE that that copy is >> in the disk drive ALL THE TIME (unless of course you're using it for >> something else). This will at least reduce ALMOST to zero the chances >> of your software getting scrambled by multiple power cycling of the hardware. >> Why? Because IF there is a floppy in the disk drive when the machine goes >> down from a power hit, it will (when the power comes back on) try to boot >> itself off of the floppy (rather than off of the hard disk). If you get >> 5 power hits in 15 minutes (for example), this can be the difference between >> losing a few temp files (through fsck et al) and scrambling your entire hard >> disk. >> >> LONG-TERM, you do need to do something to protect the PC from: >> (a) power surges (relatively cheap), >> (b) (optional but still a good idea) power hits (not so cheap, as we're >> talking about an uninterruptable power source that fits on a 120V line). >> >> I don't have any specific products to recommend here. Sorry about that. Dave Levenson (ihnp4!westmark!dave): >> I recommend the TrippLite BC-425. This unit conditions the power >> line by absorbing spikes, and providing up to 30 minutes of standby >> power from internal batteries. List price is $595. I sell one with >> every PC network server I install. See if you can find a local >> supplier. (If not, I can offer it at $525 + shipping.) Thanks, everybody! --- Prentiss Riddle ("Aprendiz de todo, maestro de nada.") --- Opinions expressed are not necessarily those of Shriners Burns Institute. --- riddle@woton.UUCP {ihnp4,harvard}!ut-sally!im4u!woton!riddle