Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!cuae2!ihnp4!houxm!mhuxt!mhuxv!mhuxo!ulysses!sfmag!sfsup!shap From: shap@sfsup.UUCP Newsgroups: comp.sys.mac Subject: Re: Surge Suppressors Message-ID: <1016@sfsup.UUCP> Date: Fri, 9-Jan-87 22:20:40 EST Article-I.D.: sfsup.1016 Posted: Fri Jan 9 22:20:40 1987 Date-Received: Sun, 11-Jan-87 07:08:31 EST References: <1094@Shasta.STANFORD.EDU> Organization: AT&T-IS, Summit N.J. USA Lines: 58 Summary: Surge suppressors are essential In article <1094@Shasta.STANFORD.EDU>, hans@Shasta.STANFORD.EDU (Hans Mulder) writes: > > Recently I had a discussion at a local computer store about power surges > and other uncleanliness on the wall(AC) power > They claimed that some of my problems with my harddisk (4 defects in 6 months) > were due to dirty power and that I should immediately buy a surge suppressor. > They basically claimed that the wall power is so bad that it can destroy > power supplies (and other parts of a computer).... Indeed wall power is horrible, and its quality depends a lot on what block you are on and which power trunk and the phase of the moon and the quality of your local power station and the current price of tea. It is possible for electricity to do oddball things, like blowing out little used portions of, say, a ROM. You won't konw until you need it. It is also easy for an unprotected computer to be turned into so much charred plastic and metal by a vagrant electrical storm. There have been several such tales of woe on the net over the years. The same holds for VCR's, Televisions, and the like. Manufacturers do not tend to include this stuff by default because it costs money, and sites with more than a few machines often have their own power conditioning, and don't want to pay the extra money. Also, it is more profitable to let you replace your PC. As to the warrantee, electrical damage comes under acts of God, and usually warrantees do *not* cover these. There are two sorts of protection you need. The first is from spikes, which are instantaneous transitions of voltage on your power line which can go as high as five times the line's rating. These little jiggles can quite contentedly blow away silicon. The second is surges, which are of longer duration, though usually not as high. These can be caused by the time lag between the grocery down the street's industrial freezer kicking in and the power company putting more power on the net. It is a feedback process, so when the unit kicks out there will be too much power for a while. Either direction is a potential problem. Some dealers will tell you that these are the same thing. They are not. Electrically they have different properties and are prevented by slightly different circuitry (mainly, some capacitor and resistor values change). You probably want a unit with a circuit-breaker rather than a fuse. They cost a bit more, but it pays off the first time you would have needed to replace the power protection. I have had occasion to be thankful.... As to brands, I use the Apple/Lemon/Orange/etc.. series, which many dealers carry. I am sorry that I do not recall the manufacturer. It is about the cheapest insurance policy you can by. Not protecting your 3,000 dollars worth of computer equipment with a $30 surge suppressor is just plain foolish. Hope that helps a bit. Jon Shapiro AT&T Information Systems