Issue 8
Publisher: Jack Burlin Editor: Patti Hammonds
February 5, 2006
IN THIS ISSUE
Your success story
Monthly product special
Kevinisms
Trivia
Articles of Interest: MOVs and Surge Suppression Capacity Part 8: "When is a toilet like a salt shaker?"
I received my Low Profile Cabinet last Saturday and it came in perfect shape. I'm already loading it with my three servers. Everything fits nicely and I was impressed with the design of this thing. It is heavy as heck, but that was expected. I liked how the internal racking depth can be adjusted by moving the rack rails deeper or shallower from their supports on the sides of this cabinet.
I was impressed on how it suppresses the noise of my loud supermicros. I added a layer of dynamat noise suppressers and sound silencing foam on the siding of this box. This addition dramatically lowers the noise of the servers to almost silent. This box with dynamat/sound proofing foam really made the servers no louder than a desktop computer.
Ian Park
Note: ISC can provide sound proofing foam or other materials for suppression of airborne or structural noise. We have materials designed for damping, barrier, absorption, or any combination of these typical noise problems.
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Our utility drawers come in a variety of styles: UD series with a face mounted drawer pull D or TD series with spring-loaded latches and optional keylocks DC series with spring-loaded latches Each 19" rack mount drawer is fully enclosed with a laser knock-out in the rear, full extension ball bearing slides, and can host a variety of media partitions. Interior dimensions are 15.825"W x 14.5"D, with 2, 3, 4, 5, and 8U versions. Finishes include black anodized, silver brushed, and textured black powder coat. Store your extra rack screws, tools, documentation,
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Is Your Surge Suppression Still Functional?
How to tell if you have exceeded the limit
Most power strips on the market today use the Metal Oxide Varistor (MOV) as the primary component for suppressing surges and spikes in electric voltage. The MOV is an electronic component that resembles a capacitor. It is typically a round disk with two electrical leads, and comes in various sizes for differing levels of protection. See the photo below of typical MOVs.
Most MOVs are made from zinc oxide
with differing amounts of manganese, cobalt, bismuth, and other metal
oxides. This matrix of materials is then placed between two metal
plates to which the electrical leads are attached. The boundary between
grains forms a diode junction, which allows current to flow in only one
direction. The mass of randomly oriented grains is electrically
equivalent to a network of back-to-back diode pairs, each pair in
parallel with many other pairs. The diode pairs react differently
at high and low voltages. When low or normal voltages are present,
there is very little current flow through the MOV. However, in the
presence of high voltages, the diode junctions break down, and a large
current flows through the MOV. Another way to say this is that the
MOV has a very high resistance at low voltages, and a low resistance at
high voltages.
When placed in series in a typical power strip circuit, the MOV clamps down on voltages to keep them at a safe level for the electrical components using the strip. Instead of the large current flowing to the protected equipment, it instead flows through the MOV where it is dissipated as heat.
However, an MOV's ability to choke down on high voltages is not limitless. The size of the MOV determines how many Joules* of energy can be dissipated. Once this limit is reached, the MOV is no longer effective, and new instances of high voltage will not be dissipated. Thus the high dollar electrical components are no longer protected once the inexpensive MOV reaches or exceeds its capacity.
Although MOVs are relatively cheap, replacing the MOV in a surge suppressor is not economically viable. It is more economical to replace the entire power strip.
Many power strips provide an LED to show that there is still some capacity remaining in the MOV. When the light goes out, it is time to get a new power strip. Until that point, there is still some surge suppression capability remaining, but it is impossible to determine the exact amount.
The SPF064-10 and SP104-10 are typical 15Amp surge suppressed power strips with LEDs showing active MOV protection.
Call us at 800-458-6255 for more
information on what ISC can do to meet your needs for
surge suppression, power strips, PDUs, UPSs, and remote
power.
Trivia Question
What is "sublimation" and what readily available compound
exemplifies this characteristic?
All correct answers will be placed into a pool for a random drawing at the end of the month. The winner will receive a free 25 foot reel of reusable velcro cable ties (part number MD88-25RLBK), plus free ground shipping. Send your answers to: Jack Burlin
See next month's newsletter for the winner and the correct answer.
Answer from January's Newsletter.
Q: What was the original color of the Ruby Slippers in the film the
Wizard of Oz,
and why were they changed to ruby?
A: In the book The Wizard of Oz, Dorothy wore silver slippers. When filming the movie, the silver slippers did not show up very well (being pretty reflective) so they were changed to "ruby" red.
The winner was Amanda Shultz at Middle Atlantic Products. Congratulations!
A Kevinism is a funny or intriguing statement or idea from our Vice President of Sales, Kevin Hunt. Kevin is a big fan of Sandra Bullock, Pizza Inn black olive pizza, and Dr. Pepper (not necessarily in that order). He is not a big fan of Chinese food, seafood, or other types of "dead" stuff.
Kevin is the epitome of "going off on a tangent." We will be having a conversation about a common daily activity, and a series of words will spark Kevin's imagination such that he instantly creates a whole new paradigm. Here are some examples:
1. When we were discussing the weather, I happened to mention that as an Air Force pilot we were always very interested about the weather. We would get weather briefings each morning, and if we happened to be flying out of our local area on a cross-country flight, then we had to have a special weather briefing, which I said was a "weather brief." Kevin immediately wanted to know what kind of weather briefs the meteorologists would wear, and whether it affected their calculations and forecasts. Kevin would say, "You know, if the weatherman is wearing "weather boxers" it might make him more likely to predict bad weather, than if he was wearing his "weather briefs."
2. There is a retail outlet in our area called the "Dollar Tree." Someone mentioned they had been there, and Kevin said, "You know, if you care for your Dollar Tree properly you can get one to grow higher denomination bills. Through carefully grafting, you can get it to actually be a Ten Dollar Tree or even a Twenty Dollar Tree."
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* A Joule is one Watt-second. A power strip like the SPF064-10 has 720 Joules of protection. It could absorb 720VA over one second, or 7200VA over .1 second, etc.
SPF064-10
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like a salt shaker?
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Part 8 Continued from January
Here is the table of the
names I have applied to each group of respondents to the survey
described in the October issue. This month we will define the
Queens of the Realm.
| The men who prefer the toilet seat up are: | Macho Men |
| The women who prefer the toilet seat up are: | Fairy Godmothers |
| The men who prefer the toilet seat down are: | Men of Leisure |
| The women who prefer the toilet seat down are: | Queens of the Realm |
| The men who prefer the lid down are: | Paleolithic Men |
| The women who prefer the lid down are: | Interior Decorators |
| The men who have no preference are: | Philosopher Kings |
| The women who have no preference are: | Warrior Princesses |
Queens of the Realm
The Queen of the Realm is one of the two "natural states" of women. Together with the Interior Decorators, this makes up 96% of the adult female population. In essence, the Queen of the Realm wants the toilet seat left down at all times because "that is the way they want it!" Who better to determine the condition and upkeep of the throne than the Queen? Also, when the Queen issues and order, she expects to be obeyed.
Men that are not Men of Leisure will argue with the Queen of the Realm. The vast majority of the time, the Queen will win the argument. There are two classic approaches they can take. The first is "for them," which usually entails a discussion of why they do not want to be surprised in the middle of the night and accidentally fall in the toilet. They hate getting wet! If this argument is not successful, it quickly gives way to the "for you" argument, where they don't want to turn the light on and consequently wake you up in the middle of the night. They don't want the light to get in your eyes, and of course they don't want you to wake up to a blood curdling scream when they fall in the toilet.
Macho Men will fight this battle over and over and over again until one of two things happens:
- The Queen of the Realm temporarily changes character into a Fairy Godmother
- The Macho Man dies
The constant stress of continuous arguing usually hastens the second outcome. The other types of men will usually surrender to the Queen's onslaught, and if they are not Men of Leisure, they will "evolve" into one. If they capitulate but do not change their classification (not becoming a Man of Leisure), they will just adopt the behavior of returning the toilet seat to the down position when finished using the toilet.
A strong and relentless Queen of the Realm is a devastating opponent. They get their way, either by inducing a behavior change, or a personality classification change.
Continued next month with the Paleolithic Men
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Information Support Concepts, Inc.
Mansfield, Texas
ISC, Information Support Concepts, Inc. offers an Extensive Selection of Quality 19" and 23" Rackmount Enclosure Computer Racks, Server Cabinets, Server Racks, 2-Post and 4-Post Racks, LAN Racks, Portable Racks, Power, Rackmount LCD TFT Monitor Keyboards, Accessories and Much More for IT-Network-Telecom Professionals.