ZEROSRGE.TXT 
 
README 
 
This file (up-dated July 30, 1991) contains several articles on 
surge protection in general, and Zero Surge in particular.  
Reprinting permission conditions, such as for User Group 
Newsletters, are provided with each paper.  This file is available 
from this BBS in the following formats:  
 
ZEROSRGE.ZIP - Entire contents in ZIP format. 
ZEROSRGE.SIT.- All contents STUFFIT format. 
ZEROSRG1.TXT - text of 1st paper "Surge `protectors': worse than 
                 useless?" 
ZEROSRG2.TXT - 2nd paper "No-Nonsense Computer Surge Protection: 
                 Wrong Choices Can Cause Failures". 
ZEROSRG3.TXT - 3rd paper "Surge Suppression for Networks: Problems, 
                 Myths and Solutions". 
ZEROSRG4.TXT - 4th paper "Surge `suppressors'revisited: a letter to 
                 Larry". 
ZEROSRG5.TXT - 5th paper "Zero Surge model ZS1800 Surge Eliminator: 
                 Product Review and Report". 
ZEROSRG6.TXT - 6th paper "Surge Protection Revisited". 
 
Notes about each of the above papers follow: 
 
1. "Surge `protectors' - worse than useless?", by Andy Baird, 
originally published in the Princeton Macintosh User Group 
Newsletter (June 1990) and reprinted in BCS On-Line Connection in 
December 1990.  This article is an excellent introduction for all 
levels of readers to the problems and shortcomings of ordinary surge 
protectors.  It is the most widely reprinted article ever circulated 
by the Macintosh User Group (MUG) News Service and has been 
reprinted throughout America, in Europe and Australia.  It was 
updated in June 1991 and published by the National Institute of 
Standards and Technology (NIST) at the NIST Surge Protection Forum 
in June 1991 (see Item 4 below).  The author is Lead Interactive 
Systems Designer for the Educational Testing Service's Technology 
Research Group.  His background includes fifteen years' work as an 
electronic technician and computer support specialist with Princeton 
University's Plasma Physics Laboratory, as well as six years' 
service in various capacities with the Princeton Macintosh Users' 
Group, whose newsletter he has edited for the past several years.  
This article may be reprinted substantially unedited by non-profit 
groups, provided the copyright notice remains intact. 
 
2. "No-Nonsense Computer Surge Protection: Wrong Choices Can Cause 
Failures", by Wendell H. Laidley, President of Zero Surge Inc., 
presented at the NIST Forum on Surge Protection, June 19, 1991.  
This paper explains, with diagrams, how ordinary surge protectors 
divert high energy powerline surges into modems and computer 
datalines.  It shows how the Zero Surge protector prevents this 
dangerous problem for all interconnected computers, and provides 
safe and reliable computer protection. 
 
3. "Surge Suppression for Networks: Problems, Myths and Solutions", 
by Wendell H. Laidley, ISPNews, March/April 1991.  This article is 
adapted from a paper presented to the Power Quality '90 Conference 
in Philadelphia in October 1990, and explains the unique power surge 
vulnerability of computer networks.  It analyses some of the myths 
of computer surge protection, and shows that many of the assumptions 
about surge protection requirements and surge protector performance 
are invalid.  Reprint permission required from ISPNews, 498 Concord 
Street, Framingham, MA 01701, Tel:(508)879-9792  FAX:(508)872-1153. 
 
4. "Surge `suppressors' revisited : a letter to Larry", by Andy Baird, 
Princeton Macintosh User Group Dialog Newsletter, June 1991.  This 
article is an actual letter written to a friend who requested help in 
justifiying purchase of Zero Surge protectors.  It is short and to the 
point, and presents the main justification reasons for purchasing 
Zero Surge protection.  The article may be reproduced substantially
unedited by non-profit groups, provided the copyright notice remains 
intack. 
 
5. "Zero Surge model ZS1800 Surge Eliminator: Product Review and 
Report", by Vernon L. Chi, Director of the Microelectronic Systems 
Laboratory of the Department of Computer Science, University of 
North Carolina, Chapel Hill.  This report is a technical evaluation
of the ZS1800 Surge Eliminator by an experienced transient 
protection engineer highly knowledgeable about the incidence, 
propagation and suppression of powerline surges.  Its technical 
level will exceed the knowledge of most non-electrical engineers, 
but its conclusions may be helpful to all interested parties.  
Copyright by author, with reprint permission non-exclusively granted 
to Zero Surge Inc. 
 
6. "Surge Protection Revisited", LAN TIMES, May 1990, p. 89.  This 
article is the most comprehensive analysis of the problem of power 
surges in networks yet presented by any major computer publication.  
It explains thoroughly the network problems caused by diverting 
surges to ground and into network datalines.  It has been widely 
quoted by engineers investigating the subject, and is written in a
style and with content that will interest and inform both technical 
and lay readers. 
 
 
Zero Surge has been discussed and/or recommended in the following 
computer publications: 
 
     - PC Magazine 
          July 1991 - "Connectivity Clinic", p.482. 
          Nov.1990  - "Spikes, Surges and Other Power Gremlins", 
                        p.333. 
 
     - BYTE 
          Oct. 1990 - "Electricity 'Sponge' Promises Surge 
                        Protection" p.48. 
          Nov. 1990 - Jerry Pournelle's Chaos Manor, p.79. 
 
     - InfoWorld 
          April 22, 1991 - Jerry Pournelle's "A User's View", p.54. 
 
     - Data Communications 
          Dec. 1990 - "Reconsidering Power Protection", p.72. 
 
     - LAN Magazine 
          Dec. 1990 - "Power Protection:How to Protect Your LAN from 
                        Electricity's Ills", p.75. 
 
     - Network Computing 
          March 1991 - "Protecting your LAN from Power Line 
                         Poltergeists", p.94. 
 
     - PC Week 
          April 30, 1990 - "Surge Protector Shields LAN Data", p 36. 
          Sept.10, 1990  - "Protecting PCs from Sags and Dips, 
                             Surges and Spikes", p.127. 
 
     - Atlantic Tech 
          August 1990 - Editorial, "You Only Think You're Safe", 
                          p.4. 
          Sept. 1990  - Computer Safety, "Zero Surge: A Warm Fuzzy",
                          p.64. 
 
 
 To obtain hard copies of any of the published articles, or other 
Zero Surge product information, or to make suggestions on format or 
content of this file, phone, FAX or write: 

               Zero Surge Inc. 
               103 Claremont Road 
               Bernardsville, NJ  07924 
               Tel: (908)766-4220 
               FAX: (908)766-4144 

and request specific items. 
 
This file will be periodically updated on the Boston Computer 
Society InfoCenter BBS (free public access 24 hours/day, 617-621-
0882) and will be identified by its revision date in the first line 
of the Readme note.  A brief description of the changes in each 
revision will be given, as follows: 
 
                July 30, 1991    Revsion of Zerorge4.txt 
 

SURGE "PROTECTORS" -- WORSE THAN USELESS? 
by Andy Baird, Editor of the Princeton Macintosh Users Group 
Newsletter, Volume VII, Number 6, June 1990 
 
Your surge protector may not be doing any protecting -- worse, it 
may actually be endangering your equipment!  A shocking expose in 
the best yellow-journalism style. 
 
 
ZZZZAAAAPPP! 
 
Jolted out of my early-morning sleep by the deafening buzz of an 
electrical arc, I knew at once something was badly wrong. I lunged 
toward the sound, which came from beneath my computer desk, taking 
in at a glance the ominous blue-white glare from my surge 
suppressor, and the cloud of black soot staining the wall behind 
It. I ripped the Mac's plug from the outlet as the arc died and an 
evil smell filled the room. 
 
After my heart had stopped pounding, I examined the remains of my 
surge suppressor. Looking at the charred interior of the case, I 
shuddered. If it had been made of plastic instead of steel, there 
probably would have been a fire.  The MOVs (Metal Oxide Varistors) 
had been literally blown apart by the force of the surge; then, 
like a welder's rod, had arced across the bare wire leads. 
 
I thanked my lucky stars that the MOVs had done their job and saved 
my Mac, while wondering whether there wasn't a better way to protect 
equipment -- a way that didn't involve an explosive failure of the 
components that did the protecting. 
 
I thought about the time, a couple of years back, when my Hayes 
Smartmodem had died during a thunderstorm, along with a couple of 
chips on my computer's motherboard. I had surge protection on the 
computer, but none on the telephone line.  When lightning struck 
nearby, a spike came up the phone line, fried the modem, then 
continued up the serial cable to kill the line-driver chips in my 
computer. After that experience, I added a surge suppressor on my 
phone line, so I was completely protected. 
 
Or so I thought at the time. 
 
Now I know I was wrong. In fact, I now realize that the modem was 
probably killed _by my surge suppressor_.  The MOVs which were 
supposed to protect my computer had done their job by shunting an 
incoming power-line surge onto the ground conductor -- _the same 
ground used by the modem as a signal ground reference_.  The result 
was a few thousand volts across the modem's inputs -- and a dead 
modem. 
 
 
EVERYTHING YOU KNOW IS WRONG 
 
I want to make three main points in this article.  First, the surge 
suppressor you own, if it's more than a year old, is probably not 
protecting your equipment, because its MOVs have degraded to the 
point of uselessness -- and there's no practical way you can test 
this.  Second, even if it's brand new, or uses expensive TransZorb 
devices instead of MOVs, it is designed to dump surge energy onto 
the ground conductor used as a reference by your modem, network 
connection or other serial device, thus endangering your peripherals 
or other networked computers even if it protects your own computer.  
Third, there is a new device which will protect your equipment over 
the long term -- ten to twenty years without endangering it. 
 
Before I tackle those three points -- and try to convince you that 
the conventional wisdom about surge suppressors is wrong -- let me 
tell you where this information comes from. 
 
 
LIGHTNING STRIKES IN THE CAPITOL 
 
The National institute of Standards and Technology, in Washington, 
DC, has a section devoted to the study of power-line surges.  The 
head of the group, Francois Martzloff, has been studying surges and 
other transient electrical phenomena for many years, resulting in 
ANSI/IEEE standards (C62.41-1980, if you're interested) defining 
commonly encountered spikes and surges.  A recent experiment, in 
which surges were artificially induced in the power wiring of an 
industrial building, yielded an unexpected result: suppressor 
protected computers were undamaged, but serial printers connected 
to them were damaged _by surges on the data input lines -- not the 
power line_. 
 
Where had these surges come from?  Martzloff and his colleagues 
finally concluded that the data-line spikes which had damaged the 
printers had been created when the computers+ surge suppressors 
shunted the excess electrical energy to the common ground conductor. 
_The printers had been killed by the surge suppressors_! 
 
Interestingly, the NIST team was not the first to arrive at this 
conclusion.  A small New Jersey company, Zero Surge Inc., had been 
founded not long before by two engineers who set out to build a 
power conditioning device which would not dump excess energy to 
ground.  We'll talk more about the Zero Surge device later... but 
now let's consider my three major points. 
 
 
THE MORTALITY OF MOVs 
 
A look at GE's "MOV Design Manual" reveals several interesting 
facts.  First, MOVs don't begin to respond to a voltage spike until 
10-40 nanoseconds.  That may sound fast, but the typical spike 
described in the IEEE standard has a rise time of just 5 
nanoseconds.  That means an MOV can't react fast enough to stop the 
most common electrical spikes... spikes the IEEE standard says can 
be expected many times a week in an average building! 
 
Second, MOVs wear out.  Every little jolt shortens the lifetime of 
an MOV, until finally it fails to provide any protection.  Those 
little jolts include the several-times-a-week spikes described in 
the IEEE standard.  A recent article in the industry journal LAN 
Times (May 1990) says: "If your surge protectors have been in use 
for a while (six months is a reasonable time), the MOVs may be 
incapable of proper performance.  Moreover, as the MOV ages, its 
clamping voltage decreases and it may begin a process called 
thermal runaway, which has resulted in fire."  (Remember, I spent a 
long time scrubbing the soot off my walls after my surge 
suppressors burned up!) 
 
A dead MOV -- more precisely, one which has deteriorated to the 
point where it offers no protection -- can only be detected with 
expensive, sophisticated test gear.  That ten-cent LED which glows 
so reassuringly on your present surge suppressor may make a good 
night light, but it tells little or nothing about whether your MOVs 
are really doing their job, or have gotten tired and given up.
I've been shown several commercial surge suppressors (a Kensington 
MasterPiece, among others) which appeared fully functional, but 
provided no surge protection whatsoever! 
 
In short, MOVs provide inadequate protection; they wear out in the 
course of normal use, and they fail without warning, possibly 
posing a fire hazard. 
 
 
WHAT ABOUT TRANSZORBS? 
 
I've always figured I was extra safe, because my Mac was plugged 
into an expensive power strip using TransZorbs instead of MOVs. 
TransZorbs (avalanche diodes) are semiconductor devices which 
respond faster than MOVs, and don't degrade with time.  However, 
I've recently discovered that they have another problem: when a 
really big surge hits, they fail "open", so they can't divert the 
surge voltage, just when they're needed most! 
 
But that's minor.  The real problem is this: just about all 
presently available surge suppressors, whether they use MOVs or 
TransZorbs, are wired to divert, or shunt, energy to ground.  As 
the NIST researchers found, this almost guarantees contamination of 
data lines, resulting in garbled data at best, and fried equipment 
at worst.  The same design flaw which cooked my Hayes modem and 
those printers in Washington is built into almost every surge 
suppressor made, from the cheapest to the most expensive.  The LAN 
Times sums it up this way: "Networks should only employ surge 
protectors that do not shunt surges to ground. If [existing] power 
conditioning devices contaminate the reference ground by introducing 
surges, it may be wise to remove such devices from a network or to 
replace them with something better." 
 
Some people may think they're protected by the use of UPS 
(uninterruptible power supply) equipment, which by definition is a 
100% battery-fed system.  But not only are UPSs quite expensive, in 
the majority of cases their inputs are "protected" by the very same 
fifteen-cent MOVs as the average surge suppressor!  (the single 
exception, Abacus Controls, licenses its technology from Zero Surge, 
the small company I mentioned earlier.) 
 
 
A SINGULAR SOLUTION 
 
So how _can_ you protect your expensive computer equipment?  The 
LAN Times has this to say: "The ideal surge protector would be a 
circuit that presents a high impedance to the surge and a low 
impedance to the [normal] power wave, while protecting the integrity 
of the ground circuit. It should also contain no degrading 
components like MOVs."  Such devices exist; they are made by Zero 
Surge Inc. 
 
If I tell you that the Zero Surge units appear to be the only surge 
suppressors on the market which work properly, you'd have a right 
to be skeptical.  After all, the power conditioning business is 
full of snake oil salesmen, each claiming that only his product is 
worth buying. 
 
We'll, I don't blame you.  I was certainly skeptical at first.  But 
after reading articles in "LAN Times," "PC Week" and "Power Quality" 
magazines and talking with electrical engineers as well as the 
president of Zero Surge, I believe the Zero Surge protectors are the 
only ones which 1) will adequately protect equipment and 2) won't 
contaminate data lines by dumping surges onto the ground circuit. 
 
The Zero Surge unit differs in four fundamental ways from ordinary 
surge protectors: 

  1. It's a series circuit with zero response time.  It 
     intercepts all surges, including the common 5 nanosecond surges 
     which are too fast for MOVs to divert. 
 
  2. It contains no MOVs or other sacrificial or degrading parts, 
     and no components are over stressed by surges of unlimited 
     current up to 6000 volts (the IEEE standard).  Its service 
     life is equal to the shelf life of its components, which is 
     why Zero Surge warrants its products for 10 years, and 
     thereafter offers to upgrade any unit to new condition at any 
     time for 20% of whatever the unit then sells for. 
 
  3. Critical for networks and modems (BBS and LAN users tak note), 
     Zero Surge does not use ground as a surge sink, but instead 
     stores the surge energy temporarily, then slowly releases it 
     to the neutral line.  This preserves the integrity of the 
     ground for its role as voltage reference by all dataline 
     interconnections. 
 
  4. Zero Surge takes the sharp leading edges off surges and noise, 
     eliminating their ability to couple into computer circuitry. 
 
Zero Surge makes 2 sizes of surge interceptors, a 7.5 Amp model 
(list $149), which is right for those of us who don't have laser 
printers, and a 15 Amp model, list $199) for those who do.  The 15 
Amp unit is offered at a special price of $169 to user group 
members.  (You won't be surprised to hear that I bought one!) 
 
Zero Surge president Wendell Laidley is a soft-spoken, straight- 
forward man who emphasizes his desire to answer any and all 
questions about his product. His phone number is 908-766-4220 (FAX 
number: 908-766-4144).  Don't hesitate to call him. 
 
 
=-=-=  SIDE BAR =-=-= 
 
 
HOW DOES IT WORK? 
 
Briefly, Zero Surge employs a 100 microHenry current limiting 
inductor, followed by a voltage limiting bridge.  The bridge 
contains several triggered energy absorbing stages that respond 
according to the slew rate and energy of the incoming surge, and 
keep maximum let through voltage under 250 volts (in UL 1449 tests 
at 6000 volts and 500 amps, let-through was 223 volts, or 42 volts 
above AC power line peak, the best ever tested by UL). 
 
The unit contains three large electrolytic capacitors.  One 
capacitor is charged to track the sine wave peak at all times; the 
other two are uncharged except during a surge.  The rated life of 
these capacitors, under 24-hour-a-day full load, is over 26 years at 
room temperature.  Regarding the claim of "zero response time," 
Laidley says, "The first component is an inductor, in series with 
the line, that responds instantly to the surge current.  The output 
rise time of this inductor is far slower than the low nanosecond 
range response time of the bridge diodes.  Zero Surge reduces surge 
rise time by approximately 40 times, thus reducing the disturbance 
below the threshold, to a point where no significant coupling can 
occur." 
 
By the way, all the Zero Surge components are in full view when the 
box is opened; there are no "hidden parts" and none of the epoxy 
encapsulation so often found in other units. 
 
(My special thanks to Chris Bannister of the Princeton Apple-II 
User Group for bringing this to my attention, and for allowing me 
to excerpt from his article on the subject.) 

