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Need an outlet or switch to avoid power surge after power failure

1358 Views 15 Replies 10 Participants Last post by  curiousB
I'd like to install an outlet or switch that will fail OFF during a power failure and not automatically turn ON when the power returns.
I live in a 3rd-world part of NJ that experiences power failures 8-12 times a year, often for no apparent reason. That's bad enough, but the odds of blowing out the FIOS system after the power comes back (sometimes only two minutes later) is more than 50%. The phone and in-person techies said the problem was unavoidable and the site visits, necessary because the 'force' of the surge when the power resumes is unavoidable.
I think if my FIOS were connected to a switch and/or outlet that stayed OFF after the power failure, that I could switch it ON after the power returns and avoid the surge. Afterall, the first thing I'm asked to do to check the problem is to reset the interface. If turning the power on and off doesn't bother the interface, then switching the outlet should have the same effect, right?
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The only device I can think of that might help would be your UPS. They can have programming that may control the return of power. Two cases, one while the batteries are still in play and the other after the batteries are depleted. Just a thought and would take some reading to see if any help.

Personally, I could easily set up a relay and delayed control to accomplish what you describe, but stopped long ago providing work-around options.

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Use a manual reset GFCI. It will need to be reset manually after a power failure.
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^^ And most come with surge protection. Many will allow a managed shut-down after a certain period on battery. I don't know if this would work for modems and such.
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Plus one, or is that two @lenaitch?, on the UPS.

I have UPS devices on all my electronics. Including my router (and modem when I had one) and I use surge suppressors on everything else. (Not just power strips, it has to be a surge suppressor!!)

There are two sides to most UPS devices. Both sides are protected by the surge suppressor portion of the UPS. Half of the outlets are also have the battery backup portion.

You can get UPS's in various sizes. The one on my main TV also powers my main router, sound bar (and it also used to power my Dish receiver until I cut the cord). I have watched TV for almost an hour while surfing the web when the power went out.

The reason I stressed surge suppressors instead of just power strips is that a lot of surges can happen in side the home. So if you have a whole home surge suppressor, which protects you from external surges for the most part, having surge suppressors on your valuable electronics, will help protect them from surges on the inside.
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1. UPS
2. Manual Reset GFCI
3. Remote Control Receptacle

Those are some ways to protect against power coming back on automatically.

The UPS is the most expensive. The other two are about equal in price.

The remote receptacle has the advantage of portability and it doesn't require working on the wiring to install it. They work like a latching relay... if the power fails, they unlatch until you re-latch them manually.

Remote Control Rcpts
OP I have a question about your FIOS. What is its actual power input? I mean, I’m sure there’s a “wall wart”/“power cord lump” of some kind that takes 120V... but it turns the 120V into something else. What exactly?

They work like a latching relay... if the power fails, they unlatch until you re-latch them manually.
You’re looking for a different word there. Latching relays are not that; much the opposite, a latching relay will stay where it’s thrown, forever, which has its uses, but this is not one of them :)
You’re looking for a different word there. Latching relays are not that; much the opposite, a latching relay will stay where it’s thrown, forever, which has its uses, but this is not one of them :)
I assumed all would know I meant an electrically latching relay since it would release when power failed. In essence, that's how those remote control receptacles are powered when turned on. The OP just wanted to keep the power off after a short failure and turn it back on when he decided the possibility of a surge had passed. The device fills the bill nicely.
Latching relays are, well the seminal example is the GE RR7. You shoot it a momentary shot of 24V and it throws “ON”. You shoot it another shot of 24V on a different wire and it throws “OFF”. If power is lost, the relay doesn’t move, which means the controlled item will get power the moment power comes back on, surges and all. So it’s a case of “using that term for that thing doesn’t work, because that term is taken by something else”.

What you are trying to describe sounds more like a holding relay, which can be implemented in an ordinary relay by having an NO contact in parallel with the “turn on” pushbutton. A momentary pushbutton turns the relay on, and then, the relay holds itself on, for as long as it’s on. As soon as the relay drops out (e.g. because power is lost), it does not self-re-engage, and the user must push the button again. Note this takes power all the time to hold on. I don’t see a passive way to shut off when power is lost, unless you have a powered device like an Arduino with a battery, monitoring for that condition. The Arduino could then use battery power to throw a latching contact to the off position.
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I chose the term "Electrically Latching Relay" specifically to make it clear that this was not an ordinary magnetic latching or mechanical latching type. An "Electrically Latching Relay" will lose its "ON" state if the system power fails. That's what the OP asked for.

Relay - › wiki › Relay
Jump to Latching relay - Such an electrically latching relay requires continuous power to maintain state, unlike magnetically latching relays or mechanically ...

As a side note, we had a tv once that turned itself on ever time the power was restored after a power failure. To guard against the tv coming on while we were gone on vacation or whatever, I used one of the remote control receptacle adapters mentioned above for their electrically latching function so the power to the tv would stay off once it failed. Worked slick as a whistle. I could have just unplugged it every time we left the house for a day or two but then it would lose its program guide info and take days to get back.
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Feed the transformer from the low voltage always on switch

Add a momintary on switch o start it.

Power goes out the switch is off, no power to the transformer to start again.


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You lifted that Wikipedia quote way out of context, it was talking about something completely different, i.e. computer RAM. It was saying in essence that the relay-RAM latch loses it grip when power is lost, and goes to an indeterminate state.

It wasn’t talking about what you were doing, and I’m sorry if you “adopted” that name for it, I’m just saying it’s a term-of-art that means something else.

It’s like if you want to call a 3-1/2” floppy a “hard drive”, I’m not here to spelling-flame you or call you wrong.

What concerns me is OP; if we send him into a shop looking for a latching relay to do what he wants; it’ll be a waste of time since what the average shopkeeper or website calls a “latching relay” does not do that.

“So what’s it called then Harper?” It’s not called anything. There’s not a name for it because it’s not a unique type of equipment, it’s simply a wiring arrangement applied to a regular relay (NO contacts hold coil energized).
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Posters, Posters, Posters, Can't we all just get along?

Can't we all just agree to disagree?
@seharper, both you and @surferdude2 could be guilty of misquoting the text from the Wiki page.

Nowhere did it say that it was referring to RAM or Random Access Memory. If you read it more closely, it was referring to stored logic/program control. Similar to ITTT. (If This, Then That) That is why it was essential for a telephone exchange.

While it is true that a Latching Relay, or Latch will keep it's contact position in perpetuity with out any constant charge, @surferdude2 found a unique type of Latch that required constant charge to keep the circuit a certain way.

So, in essence, @surferdude2 was less incorrect than you were.

Regardless, I think the OP, @papatheos was either a troll or didn't give a rat's ass about any answers to his question.
There was no problem that I was aware of. I think the OP probably got one of those remote control receptacles and it's doing what he required.
I wouldn’t do anything. FIOS is by definition glass fiber on the network side (no galvanic connection) and AC power from the mains. The problem with ADSL and Cable was when you had galvanic connections on the network and power side. Differential voltage spikes could create problems. Especially if the earth ground was suspect at the NID.

The ONT is a provider end point. It’s their problem if it fails. I really doubt is power cycling is failing the device though. That is a very basic design concept and validation exercise. Maybe you just got a bad ONT.

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