Computers & Electronics

UPS backup power supply worth it?

  • Last Updated:
  • Aug 12th, 2017 6:54 pm
Newbie
Jul 22, 2012
18 posts
10 upvotes
westom wrote:
Jul 24th, 2017 9:42 am
Then you do not know about the consumer's primary protection layer. We have only discussed the secondary layer. A primary layer does not need a protector. But it always must have an earth ground. If that street transformer does not have its required earth ground, then that primary protection layer has been compromised. Only earth ground (without a protector) provides and defines that layer of protection.
You're talking about hypothetical scenarios in which a utility company's equipment is not properly installed. A home owner has no control over that situation, so your argument is irrelevant. It must be assumed that the utility grid is correctly designed and installed, as even if it isn't there's nothing a homeowner can really do about it, let alone realize it.
westom wrote:
Jul 24th, 2017 9:42 am
Nobody, using well proven science, knew that graphite vein existed or that it would be a problem. It was discovered using an 'art' (that is impossible without science knowledge).
When new buildings are constructed a geological report is performed by a geological engineer to test soil characteristics within the property. If this "science" was done in the first place, the problem would have been discovered and a perimeter grounding grid would have been installed. The only problem is that this isn't done for houses.
westom wrote:
Jul 24th, 2017 9:42 am
Third, some best protection only has earth ground - not protector. TV cable, satellite dish, and OTA antenna has best protection only with earth ground. Only item that creates every homeowner's primary protection layer is the always required earth ground - no protector used or needed.
A protector is required (in conjunction with protection, i.e. grounding) for someone's AV equipment and compute to be protected...like the one mentioned in the original post. We're not talking about grounding satellite dishes or OTA antennas.
westom wrote:
Jul 24th, 2017 9:42 am
Sometimes 'artist' techniques are necessary because science is unknown.
There is nothing unknown about any of this aside from unknown site conditions.

If you truly believe you're some special grounding artist...I won't try to convince you otherwise. But don't go around saying things like "You are not yet ready to learn what is effective. A long list of misinformation must be unlearned.". To imply that you're the only person in the room who knows what's going on is just plain wrong.

To anyone else who may still be reading - I'll be ignoring any more of Westom's posts after this as he clearly doesn't realize what the topic of the conversation is. Let me know if there's any more questions were you want a coherent response.
Member
Dec 7, 2015
398 posts
76 upvotes
Ottawa, ON
cam1878 wrote:
Jul 24th, 2017 8:17 am
Unfortunately there isn't really a better answer than "get the landlord to bring it up to code" to resolve that kind of problem. At least not that I can think of off the top of my head.
While maybe not "better" the answer I keep getting is to buy a $75 (or so) coax isolation transformer - assuming I can't get Rogers and the landlord to cooperate on an upgrade. For most people, the answer seems to be the transformer.
Member
Dec 7, 2015
398 posts
76 upvotes
Ottawa, ON
westom wrote:
Jul 24th, 2017 10:05 am
We often say lightning will take the path of least resistance. Not entirely true. Lightning takes a path of least impedance.
The electrical stuff I learned is that it will take all paths and the current is split according to relative impedance. Higher impedance path gets less current,, lower impedance gets more current.
Newbie
Jul 22, 2012
18 posts
10 upvotes
willilumplump wrote:
Jul 24th, 2017 11:56 am
The electrical stuff I learned is that it will take all paths and the current is split according to relative impedance. Higher impedance path gets less current,, lower impedance gets more current.
While technically correct, his comment could have been worded better.

Impedance has two components, resistance and reactance.

Say you have one path that's 10 ohms resistance with 5 ohms reactance, and another that's 5 ohms resistance and 100 ohms of reactance. The 2nd has a lower resistance than the first, but still a higher total impedance

The equation is Z = R + jX, where Z is impedance, R is resistance, X is reactance. In electrical engineering, "j" is used instead of "i" for complex/imaginary numbers to avoid any confusion with current.

You are correct that all paths get a current, with the amount relative to the value of the impedances on each path. That's why you want to have your SPD to have the lowest amount of impedance possible, so the majority of the surge current flows through the short circuit rather than the load to be protected.
Newbie
Jul 22, 2012
18 posts
10 upvotes
willilumplump wrote:
Jul 24th, 2017 11:53 am
While maybe not "better" the answer I keep getting is to buy a $75 (or so) coax isolation transformer - assuming I can't get Rogers and the landlord to cooperate on an upgrade. For most people, the answer seems to be the transformer.
It's somewhat of a "treat the symptom not the cause" method, but it would still work. It'd probably be cheaper to just outfit every tenant with one than get an electrician in to revise the building grounding and pull a new wire.

If it is causing you issues, that's probably your easiest option.
Member
Jul 6, 2009
223 posts
33 upvotes
willilumplump wrote:
Jul 24th, 2017 11:56 am
Higher impedance path gets less current,, lower impedance gets more current.
And then it gets more interesting. Impedance is not constant. Impedance can change significantly with currents. Most of what we do in electronics assumes impedance or resistance is constant. But not when discussing surges.

So that impedance to protected items stays high, then impedance to what we connect a surge to (ie earth ground) must be as low as practicable.

Isolation transformer should be unnecessary. Whereas code does not require any protection on AC electric, it is required on TV cable, telephone, satellite dish, and OTA antenna. Phone line must have a protector installed by the telco for free) to provide that protection. Others simply provide best protection only with a hardwire. Code also says each must connect to the same earth ground. Cable company must and routinely does reinstall their cable if that requirement is violated.

Of course, some will intentionally violate code. In one case, a cable installer grounded his cable to dirt is a window ledge flower box.

Cable is rarely an incoming surge path. AC electric is a common incoming path. But this is electricity. To be damaged, an appliance must also have an outgoing path. Cable (or HDMI ports) is a classic outgoing path. Damage often appears on the outgoing path. Eliminate cable as an outgoing path and that surge will hunt for and find other destructive outgoing paths.

Always better is to earth that current BEFORE it can enter a building.

If I did not already mention it, even the electric utility can provide AC mains protection - without anyone's permission but yours.
Deal Addict
User avatar
Jan 13, 2004
3686 posts
271 upvotes
Lol that's me. Went looking for a UPS, discovered a masterful troll. Fun reading the thread, but feel sorry for those who got trolled.
Everything in moderation... including moderation :twisted:

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