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Old 02-02-2006, 09:36 PM   #31
tw
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Join Date: Jan 2001
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Quote:
Originally Posted by Clodfobble
That's nice, but you left out the part where for the second and third computers we bought high-end, non-Asian-market surge protectors, and they also didn't work. Or perhaps you were speaking hypothetically?
First every shunt mode plug-in protector is or is same as the "Asian-market surge protector". There is no magic in these devices. They all use same circuits discussed in that 1970 GE Varistor Manual. Furthermore, most every MOV is now manufactured in Asia.

Shunt mode plug-in protectors - cheap or expensive - are same if they have same joules rating. However many love to be scammed. They may pay $100 for the Monster Cable model that is electrically same as a $20 model from others.

Why did a protector not work? From previous posts:
Quote:
Grossly overpriced plug-in protectors forget to mention that effective protection is already inside that computer.
Plug-in protectors also forget to mention that an adjacent protector provides typically destructive transients with more paths into and through a computer.
...
So what do plug-in UPSes and power strip protectors completely avoid mentioning? Earth ground. Why? Ineffective protectors are sold mostly on myths. They avoid the most essential component of a protection 'system' - earth ground.
...
How to identify an ineffective protector: 1) Protector has no dedicated connection to earth ground, and 2) Manufacturer avoids discussing earth ground. Plug-in protectors from APC, Belkin, and Tripplite violate both points.
One final point. How typically is a modem damaged. Remember, the phone line already has a 'whole house' protector provided by Verizon, SBC, Qwest, et al.

Lightning strikes an 'antenna like' device - AC electric lines above the street. Incoming through breaker box seeking earth ground. Incoming on computer's AC wires. Bypasses power supply to connect to motherboard ground plane. Through modem, out phone line, and to earth ground via the telco 'whole house' protector.

Part most often damaged on modem is its DAA section - section adjacent to phone line. In particular, the PNP transistor that drives an off-hook relay. A small transient will leave the PNP transistor shorted. When computer is powered, then phone line is always connected through modem. Phone line acts like a phone has been left off hook.

A large transient opens that PNP transistor. Therefore computer complains about "No Dialtone Detected" because off-hook relay never connects modem to phone line.

Some are quick to assume rather than first learn underlying theory. They assume this transient entered on phone line because only modem was damaged. But notice an essential requirement. To have an electrical transient, both an incoming and outgoing path must exist. Incoming on AC mains. Outgoing on phone line. Only after transient is passing through everything in that circuit does a part somewhere in that circuit fail. Besides, why would the transient enter on phone line when phone lines already have a 'whole house' protector.

The above example demonstrates why transients on AC electric so often damage modems, fax machines, answering machines, and portable phone base stations.

Last edited by tw; 02-02-2006 at 09:40 PM.
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Old 02-02-2006, 11:14 PM   #32
zippyt
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Join Date: Mar 2003
Location: Arkansas
Posts: 7,661
look at what these folks have , I have ALLWAYS had good luck with their products , not the cheapest but I can PERSONALY recomend them .

http://www.solaheviduty.com/products/index.htm

I work on scales ,a scale ( old school analog ) is like a volt meter that goes out 7-10 decimal places , now put that in a steel mill ( think of those Big towers with power lines , they transmit KVA ( KillaVoltAmps )) or at the end of a long transmittion line AFTER 2 steel mills or just WAY out in BumFuck Egypt ,
Steel mills use HUNDREDS of KVA power per electrode ( 3 generly , but ther are some that use 1 big electrode ( DC ) , this can SERIOUSLY Fuck with the power !!!!!
Sola Isolation trans formers clean up the power about 90+% , and YES TW I have used a power analizer to test this befor .
Sola also has some of the best REAL world surge proctecters and UPSs on the market , NOT cheap but if you are looking for 1 sorce for power conditioning you can do a WHOLE lot worse than Sola .

Just my 2 cents .
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Old 02-02-2006, 11:34 PM   #33
zippyt
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Location: Arkansas
Posts: 7,661
here ya go Clod , this should help ,
http://www.solaheviduty.com/products...cr_mpcport.htm
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