Thinking of getting this UPS / protector for my Home Theater.

[westom]

Take a 1 ohm resistor and short the AC outlet , what path did the electricity take and why did the resistor get hot ? The electricity took the path of least resistance across the resistor.

Learn a difference between current sources and voltage sources. Concepts from first year engineering. It is a surge. That means same current will flow no matter what. Voltage increases as necessary so that current will still flow. Current will flow even through three miles of a least conductive material - air. Current source means surges flow even though wooden church steeples. Increasing voltage as necessary so that the same current will flow.

W = I^2 * R . Lower R means less W watts - less energy. Any device that would stop or absorb surges must increase R. Then W watts increase.

So which is it? For a protector to absorb energy (as you posted), R must increase. If an MOV become more conductive (as you posted), then R decreases. Lower R means it absorb less energy. So which is it? MOV protects by absorbing a surge? Or an MOV decreases resistance - absorbs less energy? You cannot have it both ways - even when APC says so. Please demonstrate that you understand basic electricity or surge protection. Decreased R causing increased energy says you are manipualted by advertising. My father loved such people. If made advertising so much fun.

Correct about the UL - it is also about "how it fails". UL listed appliances must fail without threatening human life. Which says nothing - zero - about surge protection. A protector that fails does no surge protection. So that it fails without taking a human life, scam protectors fail as fast as possible. That failure promotes more sales. UL does not care. UL is not about protecting transistors from surges or humans from scams. UL is only about human safety - ie threat from fire.

MOVs that protect by absorbing energy: destructive surges are hundreds of thousands of joules. Protectors (including least robust circuits in a UPS) are only hundreds of joules. Those numbers say no protection. Marketing people promoted by others as geniuses. After all, they get so many to believe hundreds of joules in a protector will stop and absorb 'hundred of thousands of joules' surges. Then when the protector fails, the naive recommend it.

Monster cable once sold speaker wire marked with speaker and amp ends. Monster said if wire were reversed, then audio sound is perverted. And thousand believed. Thousands paid $70 for Monster speaker wire because they could 'hear' a difference. Because Monster took the time to measure which end best connected to the amp. Bull.

Monster has a long history of identifying scams. Then selling the same product for even higher profits. Monster sold $7 speaker wire for $70 because that is what Monster does. And Monster is selling the same APC protector circuits for Monster profits. You think APC is credibile? Then why is Monster also selling it? Or post those APC numbers that list protection. You don't. And you cannot.

Please do not associate APC with Eaton. A major difference exists. One is credible because advertising says so. Another actually earns their credibility. Cutler-Hammer (Eaton) 'whole house' protectors actually do what protectors did even in the late 1800s. This science is well proven. Found in every facility that can never suffer damage. Is what "useful" protectors do. But APC is selling a protector described by the NIST: The best surge protection in the world can be 'useless' if grounding is not done properly.

APC is selling a protector that magically absorbs hundred of thousand of joules? Even its spec sheets say it cannot. Only a minority ask damning questions to expose advertising myths.

So how does that MOV stop what three miles of sky could not - as you claim? Its not a rhetorical question - even though you will ignore it.

Please do not waste time with credentials. Lying about that is routine. An honest person cites well proven facts and numbers. Demonstrates knowledge of simplest concepts such as current sources or W=I^2 * R. I do not care if you claim to be Albert Einstein. If you do not understand a simple equation (W=I^2 * R), then your posts are wasted bandwidth. An honest poster would have posted manufacturer specs for that protection. You do not. That defines credibility.

Now, you can be a child and get angry. Or you can be an adult and post those manufacturer specs that list protection. Your choice. I don't waste energy being nice. I work hard at being educated and honest. Honesty can be your reply to this challenge - the only facts that matter. Where are numbers (your example uses numbers) that show a decreased R creating an increased W? That proves MOVs protect by absorbing the surge? Where are those manufacturer specs? An honest person would have posted them long ago.

 

[westom]

I think it depends on your local power quality.

MarkGinger is right on the mark. If you need a UPS for such problems, then the cheapest $60 UPS does just as much as that $1000+ double conversion one.

We go find and fix the problem. One technique involves a receiver and directional antenna. Intermittent utility problems can be identified by low frequency radio noise.

 

[Modelworks]

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An honest poster would have posted manufacturer specs for that protection. You do not. That defines credibility.

It has nothing to do with honesty. I will not be responding to your postings anymore . I have said all I need to say. I learned a long time ago that changing someones mind who has already decided they can't be wrong is wasted energy, even more so when they are online. If you want to keep talking about 3 miles of sky, surges, or pink elephants that is your choice. If you really want to help and educate people you are doing it the wrong way.

 

[Emulex]

don't forget all it takes is losing your ground. easy to do with squirrels/bad fuseboxes and all your ups/protection bars become nothing. hence why you never ever unplug a live outlet by pulling the plug - flyback spark has nowhere to ground but your equipment.

if you've never seen crazy power before its something alright. the guy is right i've seen power fluctuate so bad endlessly that a matrix 5000 (with about 10 car batteries) ran itself out of power switching on/off because of inconsistent power. Think long and hard about the ground scenario i mentioned above. it is not that hard to have a ground go bad and lose ALL protection instantly.

And no protection from any surge device will cover that scenario.

Yeah datacenter folks tend to see the worst scenario's play out. nothing quite like a 440 liebert get taken apart by a rookie throwing lightning bolts across the floor to make you jump.

 

[westom]

It has nothing to do with honesty. I will not be responding to your postings anymore .

Good. No more lies about how UL says which protectors work. Wild speculation that hundreds of joules absorb destructive surges that are hundreds of thousands of joules. Myths about internally generated surges. If you had those credential, then you understood simple and relevant concepts such as current sources. Or quote each manufacturer spec number with why it is significant. You don't.

Challenge was to provide manufacturer numeric specs. No such specs exist - as proved by ignoring the challenge. Honesty is the topic.

OP's concern is well proven facts and simple science from even 100 years ago. Superior protection for tens of times less money is a properly earthed 'whole house' protector.

A UPS is temporary and dirty power during blackouts. Neither claims nor does it provide useful protection. Near zero protection in a power strip or UPS is not useful. Protection means protecting everything - including smoke detectors that are important especially after a surge. A least expensive solution is also, overwhelmingly, the best. One properly earthed 'whole house' protector from responsible companies mean massive energy dissipates harmlessly outside a building. Protection is always about where energy dissipates.

A $15 Apc, Belkin or other model with light that will only report an unacceptable failure mode? That will still report a degraded protector as good? It does not claim protection from typically destructive surges. And must be protected by a 'whole house' solution. Munitions dumps, telcos, Air Force bases, and everywhere that damage cannot happen use a proven 'whole house' solution. And do not waste money on APC, Belkin, or magic box protectors.

Protection is always about a shortest connection to earth. Professionals use 'whole house' protectors with the only item always required to have that protection. A short (low impedance) connection to single point earth ground. Even Franklin's invention would be useless without earth ground. Technology is that old, that well proven, and that simple. And is the least expensive option.

Earthing is more than making a surge protector effective. In one home, lights still worked even though earth ground was missing. So earthing was ignored. When a wire inside a street transformer failed, then electricity used the home's gas meter. Fortunately nobody was home when that house exploded. Just another reason why informed homeowner inspect an all so critical earth ground. Only item that also makes a surge protector so effective.

A protector is only as effective as its earth ground – where energy harmlessly dissipates. As was true even 100 years ago.

 

[hashish]

Wow, this thread got pretty nasty, but I just wanted to say one thing.

Largest gauge wire in your home is usually 3 gauge wiring which will fails over 300-400 amps. So the surge protector just needs to protect the devices until the current ramps up to home wiring failure limit.

So just make sure everyone knows, you

 

[Crow550]

I decided to pass on a UPS in the living room....For now....I mean my stuff should be fine with whatever surge protector I guess I won't worry.

The power did go out a lot in December. It's the surge that happens from the power line breaking or whatever breaking that worries me. When the power goes out then on then out.

Maybe get one for my PC so I turn off cache flushing on the hard drive.

However I have yet to have a device die from a power outage so I assume my House is well grounded.

 

[westom]

Largest gauge wire in your home is usually 3 gauge wiring which will fails over 300-400 amps. So the surge protector just needs to protect the devices until the current ramps up to home wiring failure limit.

You are confusing numbers for 60 Hz or DC power with electricity with surges that perform quite differently.

For example, an 18 AWG lamp cord is rated for 10 amps. That means it will conduct 60 amps safely. And will conduct something less than 60,000 amps from a surge.

Do not apply low frequency electric concepts (what electricians are trained in) with another type of electricity that performs differently.

Whereas wires with sharp bends and splice conduct 60 Hz electricity quite well. Those same wires are poor conductors of a surge.

Whereas 100 amps on a 20 amp circuit will cause the circuit breaker to trip without damage. The same circuit breaker will not trip even after 300 consecutive surges at thousands of amps. And if that breaker does trip, a surge current will continue to flow through that breaker.

A house grounded to only meet post 1990 code may not have earthing for surge protection. Reasons why were posted. What a homeowner must inspect to both meet and exceed code for surge protection was also posted.

No surge exists when lights are flickering as described. Those are voltage drops - voltage below 120 VAC. Surges means 120 VAC lines well exceeds 300 volts.

Normal household electricity is mostly concerned with wire gauge - thickness. Surge protection is mostly concerned with shorter wire length, no splices, no sharp bends, wire not inside metallic conduit, etc. Electricity with a rather different behavior. And is conducted on same wires.

 

[Crow550]

So should my equipment be fine then?

 

[westom]

So should my equipment be fine then?

Again, you concern is anomalies that can overwhelm protection already inside those theater components. If a surge is permitted inside, then it might find earth ground destructively via a TV's coax cable or HDMI cable. Your obligation is to make sure transients have no reason to be inside the house. How to do that was described earlier. If you do not have earthed a 'whole house' protector in the breaker box, then your appliances (including furnace and refrigerator) are at risk. You must earth that energy before it can enter the building.

How great is the risk? Such anomalies occur maybe once every seven years. Taking a neighborhood survey for the past decade might say more. Simpler is to upgrade earthing and a 'whole house' protector. And to confirm the telephone ‘whole house’ protector and cable ground block also make the required ‘less than 10 foot’ connection to earthing. And finally to inspect your primary surge protection system as demonstrated in this picture:
http://www.tvtower.com/fpl.html

 

[simonizor]

I have this surge protector/ups. I got it unused at a garage sale for $10. It didn't come with any software or anything to shut down the PC when power goes out, but I don't really need that. The most that happens around here is the occasional power flicker caused by lightning, etc, so just keeping my devices powered for the second or two that the power is off is all that I need it for.