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-   -   Whole House and Secondary Surge Protection (http://www.diychatroom.com/f18/whole-house-secondary-surge-protection-160789/)

Thadius856 10-22-2012 12:03 AM

Whole House and Secondary Surge Protection
 
Been considering both Whole House and Secondary Surge protection from some time.

I've cleaned up and wired most of my panel myself. Is a whole house protector something that I can reasonably complete, or should it be left to professionals?

Do Secondary Surge protectors actually work?
Is a 2-pole model better than a 4-wire model, or vice versa?

I have room for either (2 free spaces, or I could double-tap the dryer breakers) and feel confident I could install my own secondary surge protector.

This is on a 100A 16-space (8 double, 8 single) Square D Homeline box.

gregzoll 10-22-2012 07:44 AM

If you think they work, that is up to you. Nice piece of mind, but in reality, nothing protects from a direct lightening strike.

Thadius856 10-22-2012 07:46 AM

Located in the Central Valley of Northern California. Approximately 30 days of rain per year here and lightning strikes are fairly rare compared.

Was interested more in case of a surge induced by a blown transformer, downed pole, etc.

Does that change things any?

gregzoll 10-22-2012 07:49 AM

Same action would be as if you got hit with a direct lightening strike. Again, nothing will protect you if the main breaker does not trip quick enough, due to a high surge in current.

As for a downed pole, power can still be running through the wires, until the POCO disco's the power to that circuit.

Thadius856 10-22-2012 07:50 AM

Shucks.

Back to the drawing board, I guess. Good strips for the electronics and UPS for the computers, I suppose.

gregzoll 10-22-2012 07:54 AM

Never stated to not use it, just stated that they are only worth the peace of mind, just like surge strips. We put one on our house, after the Ice storm in 2006, in 2007 after we got our Plasma, due to I wanted a layered sense of protection. Surge protection devices do work for the small transient spike of a few milliseconds, but a long turn high voltage spike longer than a few seconds, as I stated before, nothing will protect.

westom 10-23-2012 11:05 AM

Quote:

Originally Posted by Thadius856 (Post 1035567)
Was interested more in case of a surge induced by a blown transformer, downed pole, etc.

A 33,000 volt line fell upon local distribution. Electric meters literally exploded as much as 30 feet from their pans. Many with power strips had damaged power strips and appliances. At least one has seized circuit breakers.

But my friend knows someone who has done this stuff. He only had one 'whole house' protector (most important) that was properly earthed. He had electric meter damage. But nothing else damaged. Even his protector remained functional.

Important is the protectors size. Should be at least 50,000 amps to make all surges irrelevant. Also necessary to protect power strip protectors.

busman 10-23-2012 11:34 AM

Quote:

Originally Posted by gregzoll (Post 1035569)
Same action would be as if you got hit with a direct lightening strike. Again, nothing will protect you if the main breaker does not trip quick enough, due to a high surge in current.

As for a downed pole, power can still be running through the wires, until the POCO disco's the power to that circuit.

Really? I have first-hand evidence to the contrary. Had a power line struck by lightning an a cul-de-sac. There were 7 houses on the transformer. I ended up visiting all seven in the same day. Results were 5 homes lost basically everything with a computer chip: microwave, tv's, etc. One house had minimal damage (a few smoked surge strips) and a small (looks like an aerosol can cap) surge suppressor at the panel that had a hole blown out the side. One house didn't even know anything happened. They had a high quality (about $250) whole house surge protector installed.

What's the basis for your statement?

Mark

westom 10-23-2012 05:44 PM

Quote:

Originally Posted by busman (Post 1036386)
Really? I have first-hand evidence to the contrary.

The first thing that makes me suspicious is associating "high quality" with a dollar number. How many amps was the protector rated? Only specification numbers have any significance. Sometimes the most expensive protector is the worst. Because so many only look at dollars rather than spec numbers.

Second, you discuss protection in terms of a protector. No protector does protection. That was only a connecting device just like a wire. Protection is always about earth ground - where energy is absorbed. A ground that must both meet and exceed code requirements. When damage occurs, earthing is the first thing inspected. A term called 'low impedance' (not relevant to anything in code) is a critically important requirement.

Third, no mention of single point ground. For example, if AC electric enters on one side of the building. And cable TV on the other. Then appliances (even not directly connected to cable) can become victims. Another term that defines protection: single point earth ground.

Fourth, the 'whole house' protector is only 'secondary' protection. Damage to all homes implies the common transformer ('primary' protection) was missing its earthing. Therefore lightning could have connected a 4000 or 13k primary directly to every appliance in every house.

Lightning is not a high energy transient so popular in myths. If lightning creates that plasma connection inside a transformer, then a high energy source (utility provided AC electric) does most damage to all connected homes. A picture demonstrates what every informed homeowner should inspect to have a functional 'primary' surge protection layer:
http://www.tvtower.com/fpl.html

But again because many overlook the concept. A protector is only a connecting device similar to a wire. Protection is done by a 'device' that harmlessly absorbs hundreds of thousands of joules. A protector is only as effective as how and what it connects to - single point earth ground.

Thadius856 10-23-2012 09:07 PM

This is all very interesting stuff. Very anecdotal, but still fun to read.

Unfortunately, I'm even farther from knowing the answers to the questions in the OP. :\

Quote:

Originally Posted by Thadius856 (Post 1035495)
I've cleaned up and wired most of my panel myself. Is a whole house protector something that I can reasonably complete, or should it be left to professionals?

Do Secondary Surge protectors actually work?

Is a 2-pole model better than a 4-wire model, or vice versa?


mpoulton 10-23-2012 09:13 PM

Quote:

Originally Posted by busman (Post 1036386)
Really? I have first-hand evidence to the contrary. Had a power line struck by lightning an a cul-de-sac. There were 7 houses on the transformer. I ended up visiting all seven in the same day. Results were 5 homes lost basically everything with a computer chip: microwave, tv's, etc. One house had minimal damage (a few smoked surge strips) and a small (looks like an aerosol can cap) surge suppressor at the panel that had a hole blown out the side. One house didn't even know anything happened. They had a high quality (about $250) whole house surge protector installed.

What's the basis for your statement?

Mark

That's an interesting anecdote, but there may well have been other factors that affected the results. Physical routing of the service feeders is likely to be a big contributing factor to lightning strike damage. The home's grounding system is an even bigger contributor. A good surge protector may help, but it's not a solution by itself - and luck is a huge factor since you never know exactly what part of the POCO equipment is going to get struck.

westom 10-24-2012 06:56 AM

Quote:

Originally Posted by Thadius856 (Post 1036784)
Unfortunately, I'm even farther from knowing the answers to the questions in the OP.

Anyone who can change a circuit breaker can also (obviously) install a 'whole house' protector. These are even sold in Lowes and Home Depot. But the point about correct installation (ie earthing) is critically important. Since earthing (not the protector) defines protection. Proper earthing of every incoming wire (not just AC electric - every wire) is critically important to installing protection that works. So that even direct lightning strikes are irrelevant.

Anyone can install that protector. But only those who learn how to install them properly will have sufficient protection. A previous post defined some numbers and concepts including 50,000 amps and 'low impedance' connection to single point ground. Factors that define a successful installation.

Protection is so easy, simple, routine, and effective that damage is considered a human failure or mistake. In every protection system and for all types of surges, how a typically 20,000 amps current gets to earth is the relevant question. Whether from a direct lightning strike or when a stray car hits a pole, that one solution (earthing) means nobody even knows a surge existed. Even the protector remains unharmed when properly sized and earthed.

Anybody can install it. But only most will install it correctly.

bud-- 10-24-2012 12:05 PM

Excellent information on surges and surge protection is at:
http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
published by the IEEE (a major organization of electrical and electronic engineers).
And also:
http://www.eeel.nist.gov/817/pubs/sp...%20happen!.pdf
published by the US National Institute of Standards and Technology

The IEEE surge guide is aimed at people with some technical background.

Quote:

Originally Posted by westom (Post 1036363)
A 33,000 volt line fell upon local distribution. Electric meters literally exploded as much as 30 feet from their pans. Many with power strips had damaged power strips and appliances. At least one has seized circuit breakers.

But my friend knows someone who has done this stuff. He only had one 'whole house' protector (most important) that was properly earthed. He had electric meter damage. But nothing else damaged. Even his protector remained functional.

The voltage limiting elements in almost all surge protectors are MOVs. They can handle thousands of surge amps for the perhaps 100 microsecond duration of a surge from lighting. But they will be rapidly destroyed by the longer duration of crossed power wires (which is not a "surge"), particularly if there is more than a very brief contact. The IEEE surge guide has information on page 11 and 15.

UPSs may protect by disconnecting and some plug-in protectors also disconnect on overvoltage (I have never seen one). Crossed power wires are rare and protection is difficult.

A service panel protector can protect from surges produced by lightning coming in on the power service wires, even a very close strike. Service panel protectors do not necessarily protect from high voltage between power and phone/cable/... wires. An example is in IEEE surge guide starting page 30.

Normal and abnormal utility operations are also sources of damaging surges.

Service panel protectors are fairly easy to install. You install them in the service panel where the neutral and ground are bonded, and where the earthing system is connected. The protector has 3 wires - one for each hot and one for the neutral/ground. Keep wires short and straight as possible. The IEEE surge guide has general information starting page 21.

When using a plug-in protectors all interconnected equipment needs to be connected to the same protector. External connections, like coax also must go through the protector. They work by limiting the voltage from each wire to the ground at the protector. A surprisingly small energy can reach a plug-in protector. A protector with high ratings and connected as above is likely to protect from a very near very strong strike.

Quote:

Originally Posted by westom (Post 1036363)
Important is the protectors size. Should be at least 50,000 amps to make all surges irrelevant.

The IEEE surge guide has recommendations for ratings on page 18.

Quote:

Originally Posted by westom (Post 1036363)
Also necessary to protect power strip protectors.

Complete nonsense.

Thadius856 10-24-2012 02:00 PM

That NIST document was exceptionally helpful.

I had planned on adding a coaxial protector and a telephone protector at the demarks. The multi-protection device shown on page 19, figure 3 is of interest. Does one of these devices provide any more protection than protectors in each demark tied back as in figure 2?

Last... my current cable demark is attached to an exterior clamp on my service panel door and my telephone to a galvanized water pipe. Would I get better results if I tie into the neutral/ground bar as show in figure 2?

westom 10-25-2012 01:14 AM

Quote:

Originally Posted by Thadius856 (Post 1037137)
Last... my current cable demark is attached to an exterior clamp on my service panel door and my telephone to a galvanized water pipe.

Absolutely critical is every incoming wire connected low impedance (ie 'less than 3 meters') to same earth ground. You describe grounding that makes damage easier. 'Whole house' protector for AC electric, protector installed for free by your telco (inside the NID), and a wire (no protector) for coax cable all meet and be earthed at the same electrode. Single point ground.

Any protector that does not make that low impedance connection is, well, according to the NIST document:
Quote:

What these protective devices do is neither suppress nor arrest a surge, but simply divert it to ground, where it can do no harm. ...
The best surge protection in the world can be useless if grounding is not done properly.
IEEE page 42 figure 8 even shows a protector earthing a surge 8000 volts destructively via a nearby TV. That protector was not properly earthed. So it earthed that surge destructively via any nearby appliance.

Coax cable needs no protector. Best protection is a direct wire connection to earth. A protector is only needed when that wire cannot connect directly to earth. Cable company should have already earthed that cable.

Secondary and 'whole house' protector are same thing. Each protection layer is only defined by what does protection: earthing electrode. So that current need not hunt for earth destructively inside.

Primary protection layer is installed by the utility (as discussed previously). Secondary protection layer is defined by an earthing electrode at the service entrance. All incoming wires must connect to that electrode before entering the building. That electrode (connected directly or via a protector) is the secondary protection layer.

bud wasted no time posting cheap shots. He only joined this forum because I posted here. He has been doing cheap shots for almost ten years. His job is a sales promoter of protectors that do not even claim to protect from destructive surges. Ask him for those manufacturer specs. He will never provide them. This discussion will become increasingly nasty as bud does what he does best. Post mockery and insult. And never post any spec numbers.

A protector is only as effective as its earth ground. Protectors only make a connection to what absorbs hundreds of thousands of joules - the earthing electrode. Effective protectors always make a low impedance (ie no sharp wire bends, no splices) connection to single point ground. Because protection is always about where hundreds of thousands of joules harmlessly dissipate.

Apparently you must fix the only component that must always exist in every protection system. Some protection systems have no protectors. But every protection system must have a single point ground. Apparently you have described multiple grounds.


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