Meanwhile, you also *know* UL does not care whether any protector does protection. UL is about human safety. Telling me how to think when you did not even know that? Your posts are intentionally insulting. You did not even know what UL tests for. Protectors could even fail during UL1449 testing. And still be listed. As long as failure does not threaten human life. Please stop posting nonsense such as UL test whether a protector does protection. UL does not care. That is not what UL tests for.
UL refuses designs with lack of protection on the input as part of the safety design of the product. The reason being that if the product were to encounter a surge during normal use it cannot fail in a way that would harm the user. It isn't about if the device fails but in how it fails.
If the MOV decreases resistance, then is absorbs less energy. But you claim protectors work by absorbing surges as heat? Which is it? You cannot have it both ways. And since you did not ask such damning questions, you are now trying to teach me how electricity works?
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. That heat consumed part of the energy. When designing a circuit I had to account for every bit of energy, not just the theoretical based on part values, but losses from heat in the pathways, the solder connections, even the length of the leads to the components .
How do MOVs at hundreds of joules absorb surges that are hundreds of thousands of joules? Remember, I designed protectors. You did not.
Some of the energy gets converted into heat. As for what I designed here are my credentials.
Masters in Electrical Engineering -NC State University
Aviation Electronics and Power production - US Navy
Supercomputer networking interconnects - Sandia National Labs
Consumer Electronics Production and Design -General Electric
Product failure analysis - Sharp
I asked this question repeatedly. To avoid admitting to being scammed, you avoided those numbers. Now you are telling me that ad men know more than engineers? That spin doctors are smarter? Again, please stop insulting me with lies. Ask how a protector works. Do you also tell your doctor how to diagnosis cancer?
I don't get into numbers because people visiting here do not want to hear theory, they want advice on what they can buy not a lecture on electrical theory.
A tvs diode will stop a surge? How does it stop what three miles of sky could not? Again, either apologize for not knowing this stuff. Or tell me how a tvs diode blocks what three miles of sky could not. If a tvs diode blocks surges, then you need no surge protection. Because every appliance has protection even better than that.
tvs diode conduct when the limit is reached, similar to a zener providing an alternate path for the surge.
Neither wood nor less conductive air stops surges. And certainly not a tvs diode.
You seem to keep getting stuck on every surge being a direct strike and that isn't the case at all. Do you think that companies like Eaton and APC do not test their products ? Do you think they just say lets throw some mov and tvs diodes on here, and oh lets put some inductors and capacitors for the hell of it and ship it ? Of course not, they both send huge amounts of surge currents , brownouts, overvoltage, through products to verify they do work for their intended use.
And so the always must be answered question. Where does energy dissipate?
Part of the energy is dissipated as heat or even physical force moving the conductors when large discharges occur. Other times it also is dissipated as light, hopefully not in the home
Why does that plug-in protector not list protection in its numeric specs? That is everything you need know. Because it does not claim to protect from typically destructive surges. It claims to protect from surges too small to overwhelm protection already inside each appliance.
Most protectors do list their specifications, or at least the ones I buy do.
Meanwhile an IEEE paper in the late 1970s defined how surges enter a home. Lighting striking wires down the street means 20,000 amps entering a home. Speculate all you want about mythical 10 amp surges. But surges that do damage are hundreds or thousands of amps.
Again , surges are created in more ways than lightning strikes. Lightning is a small part of the surges that occurs in power systems.
Your only number 10 amps says a surge so trivial as to cause no appliance damage.
A surge of 3A @ 600V will destroy most power supplies that convert to DC without some form of protection. The sound of capacitors blowing would sound like fireworks
I was probably doing this stuff long before you even existed. It is one thing to ask why contradictions exist. Why do advertisements claim protection that is not defined in numeric specs? It is another to tell me knowledge that also says you did not even take even one circuits course. Tell me what wire impedance is and why it is important.
I have spent more time with circuits than I did with people . I did read the work of that Kirchhoff guy, it was a bit long winded and I didn't care for the plot much but the characters were pretty detailed and the ending didn't leave me hanging like that Maxwell guys stuff. Still Tesla is where its at if you want some really good reading.
UL is only about human safety not surge protection.
They are not exclusive. A product cannot fail in testing in such a way as to start a fire or pass a surge current through an exposed surface should it fail.
A tvs diodes never stopped what miles of sky cannot.
It isn't supposed to. It can divert surges within its rating though.
Surges even conduct through wood. Protection is always about where energy dissipates. W=I^2 * R .
And when the surge conducts through the wood why isn't the energy that dissipates into ground the same as the source ? Why does the wood heat up ? What produced the heat ?
A protector is only as effective as its earth ground.
A protector does not rely on earth ground. It relies on an alternate current pathway that can take many forms not jusst earth ground. A surge on a DC power source provided by batteries cannot make use of earth grounding but still can use surge protection . An AC source out of a transformer can not make use of earth ground. If I took a 1:1 transformer and powered several TV and one of those TV failed in a way as to induce a surge in the power then no amount of earth grounding would matter to the other TV. MOV could still stop the surge and no earth grounding is needed. Large motors use surge protection circuits and are powered off lines that have no earth ground.
Only one of us designed these things at the solder the parts level using datasheets, with numbers, and without damage during each direct lightning strike. Please stop trying to educate me using myths, lies, and no numbers. That is only insulting.
Me thinks he doth protest too much.. I am not going to get into a pissing match over what you know or don't know because I don't know you personally. I will say again that people coming for answers are not looking for a lecture in electrical theory with formulas and lab experiments, you only put off the person asking when you do that. I see it time and again , someone wants information on something or is wanting to try something new and people reply with information that is so complex and overwhelming that it scares the person away . So many people are turned off by learning electronics because the first thing they hear when asking questions is all the math and physics and not the practical side. For example someone asked about learning microprocessors. They got replies telling them about CISC, RISC, clock speeds, emulators , compilers, ADC, etc. The person almost gave up. Instead I told them to buy an arduino kit, download the software that is free and try some simple things like blinking an LED. There is a place for theory and formulas , but using it for beginners is going to just get an okay response without helping much.
No protector works by absorbing a destructive surge. If it did, then protection inside every appliance is the only protection needed.
Any resistive element can absorb a surge. The energy is converted to heat if the element is large enough it can absorb the entire surge.
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