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Over voltage protection!!

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Mar 26, 2022
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I have recently been getting over voltage faults in my area (EU220v) of over 350v!
I feel like one day when I'm not home my pc is going to get fried!
We do use Automatic Voltage Stabilizers but their correction range is lower that required (typically 170v- 270v) which is not enaugh in an area where long 400v faults are common!
These are the AVS that we use:
My question is if I run two of these devices in series meaning one powers the other, will it encrease the correction factor from 100v to over 450v?
 
FGS, please don't use imgur!

I've been having the opposite here, as indicated by my sig.
 
Damn 400 volts? How the hell do electrical appliances survive there?
Doesn't your UPS shut down when the input voltage is too high? Running 2 in series probably would not work if it works that way.
 
I would check to see what the spec sheet says, but somehow I doubt it.
That side of the planet is mainly 220V RMS 50hz I believe? So peak voltage would be about 310V ish. If you're getting 350 RMS surges, yikes!!
For that, maybe just get a cheaper surge protector or a whole home surge protector and plan on replacing it so often after the MOVs get cooked?
 
Out of curiosity OP, have you had an electrician out already to check things out?

I've been told a compromised neutral on the utility side with improper bonding can cause transient issues. May not be applicable since different electrical system (US, not EU), but might be worth a discussion to at least rule out an underlying cause if it is a potential issue.

If you are worried about your equipment, one option as a stopgap solution might be look at a product that carries insurance/reimbursement policies for attached equipment in the case of damage.
I know a number of APC products come with these in the US, and also have a self-test LED indicator (so when they go bad/cook you can see it immediately). Might be worth looking into.
 
Out of curiosity OP, have you had an electrician out already to check things out?

I've been told a compromised neutral on the utility side with improper bonding can cause transient issues. May not be applicable since different electrical system (US, not EU), but might be worth a discussion to at least rule out an underlying cause if it is a potential issue.
This. The source of the issue is almost certainly a fault in the neutral wire in a three-phase power distribution wiring (and 3-phase works the same way whether in Europe or the US). The voltage in a 230V socket can reach 400V in the worst case, which is the voltage between two phase wires.
(US also has a split-phase system where 120V+120V add up to 240V for large consumers, and a neutral wire fault has similarly bad consequences there.)
 
I use 2 of these for my TV/audio/video/computer electronics:

Super-Solid extension lead 5-fold with overvoltage protection (13,500 A, multiple socket with 2.5m cable and switch - made of break-proof polycarbonate)
Screenshot 2024-01-20 192812.png


 
I also have a ton of surge protectors, but at 400V they will all fail.
 
Some years ago i had the same issues with OVP, new neigbourhood and still under construction even now.
This saved me from 380V many times, it just has to be re-arm sometimes.
https://www.katranji.com/tocimages/files/528336-525062.pdf
1705778346015.png


Cheap also.
Hope that helps.

No UPS or voltage regulator i know works from 100v to 500.
Maybe check Eaton
 
My question is if I run two of these devices in series meaning one powers the other, will it encrease the correction factor from 100v to over 450v?
Nope, better don't do it. Even hooking up a UPS with built-in rudimentary stabilization into a dedicated stabilizer may cause serious issues. I almost burned my bosses EATON while trying to hook up his gas boiler. UPS transformer started to heat up immediately and went into thermal shutdown. Fortunately it survived. Not sure what's the science behind this, but I'm sure as hell ain't gonna test it again.

Plus, when you have spikes up to 400V, you may want it to go into automatic shutdown anyway, cause this usually means something crazy is going on with your grid.
And if you really need something to be powered all the time - then it's better to get a UPS just for all the critical stuff.
Hell, last year during all the bombings we had crazy spikes as well, and even not so scary jumps to ~300-ish volts would wreak havoc on UPSes and stabilizers(my old trusty SVEN Reserve would start perpetually clicking away, until powered off).
 
Damn 400 volts? How the hell do electrical appliances survive there?
Doesn't your UPS shut down when the input voltage is too high? Running 2 in series probably would not work if it works that way.
They don't, we have to make sure to unplug everything when we see extreme weather!
 
I have recently been getting over voltage faults in my area (EU220v) of over 350v!
I feel like one day when I'm not home my pc is going to get fried!
We do use Automatic Voltage Stabilizers but their correction range is lower that required (typically 170v- 270v) which is not enaugh in an area where long 400v faults are common!
"Long 400V faults" means they don't just last a fraction of a second but rather many seconds or even minutes, right? I'd worry about all electric appliances, heaters, motors, lamps, everything can seriously overheat and catch fire, and capacitors or other electronic components may explode. An overvoltage protector (for the entire house/apartment!) such as the one @taka suggested will keep you safe - but often without power.

Do you have 3-phase power in your home? Also, do you sometimes see an undervoltage instead of overvoltage?
 
Even hooking up a UPS with built-in rudimentary stabilization into a dedicated stabilizer may cause serious issues. I almost burned my bosses EATON while trying to hook up his gas boiler. UPS transformer started to heat up immediately and went into thermal shutdown.
Something wrong with the UPS or stabilizer output is poor, perhaps?
Hooking up transformers in series to accommodate high input voltage is theoretically sound. Not sure about the "auto" part of the regulation mechanism tho.
I suppose the limiting factor would be how the first regulator in the series would function, if it did at all...

Hell, last year during all the bombings we had crazy spikes as well, and even not so scary jumps to ~300-ish volts would wreak havoc on UPSes and stabilizers(my old trusty SVEN Reserve would start perpetually clicking away, until powered off).
Our voltages actually stabilised after the shells started dropping. :D
 
"Long 400V faults" means they don't just last a fraction of a second but rather many seconds or even minutes, right? I'd worry about all electric appliances, heaters, motors, lamps, everything can seriously overheat and catch fire, and capacitors or other electronic components may explode. An overvoltage protector (for the entire house/apartment!) such as the one @taka suggested will keep you safe - but often without power.

Do you have 3-phase power in your home? Also, do you sometimes see an undervoltage instead of overvoltage?
Yes the average voltage is 190-219v in rare cases 350-390v
I only have single phase
 
The only way to get 350-390V range in AC power is to have two DIFFERENT phases plug into one device.
Example : Instead of "L1" being the phase, and "N" being neutral, you swap "N" with "L2" or "L3" from seperate circuit in electrical box.
You cannot get 350V+ from single phase, since that would mean a VERY big problems on transformers and almost everything after it would fry at that point (300V is max. I seen things go on one phase [special equipment], with vast majority giving up beyond 270V or around 10-15% higher voltage than normal).

I wouldn't be surprised if someone is simply trying to power 3-phase equipment illegally bridging phases to each other and causing your issues (3-phase equipment requires 350-400V to operate, based on 220-240V single pahse).
Unless he is found and stopped, just buy surge protector mentioned previously and set it to ~250V max. it will "kill" power the moment something goes higher than set value (preventing your devices from being fried).

PS. You could ask neighbours, because this type of thing should be limited to one electrical panel, since otherwise A LOT more people would be complaining about voltage stability (with electrical equipment dying/frying itself all around them).
And by "A LOT", I mean whole street or city block (depending on where faulty transformer is located).
 
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If the problem is caused by bad neutral, connecting an additional large load such as a space heater or hair dryer should lower the voltage significantly. I'd expect a drop of tens of volts.
 
That would be a nice test, but I am not sure I would be willing to put anything of mine across 400V
 
If the problem is caused by bad neutral, connecting an additional large load such as a space heater or hair dryer should lower the voltage significantly. I'd expect a drop of tens of volts.
Unless your electric grid compensates for additional load.
Keep in mind : Power grid is monitored all the time to prevent exactly what you are trying to do from ever happening.
Too big of a load may blow up transformer (or wires), that provide power to yours and neighbor's houses.
In best case, fuses before your house blow up.
 
He is just talking about a space heater.

But I think it best not to mess around with 400V
 
He is just talking about a space heater.
A "dumb" heater doesn't care about voltage. Cool it enough and they will be fine regardless of voltage.
Still, it does not "fix" the issue though. He will still have to check when voltage get's up, hook up heater, check voltage again, connect other stuff if it goes low enough alternatively connect more heaters (?) if it doesn't, and then disconnect whatever heaters he connected when voltage spike is over and things get back to normal (otherwise he get's too low voltage for stuff to work, not to mentioned electric bill).
It's WAY too much gymnastics to make it work long term.
 
Yes the average voltage is 190-219v in rare cases 350-390v
I only have single phase
Do you have access to any metal objects in the house that are reliably grounded? Lightning protection would be the best, or central heating radiators. Water pipes and earth contacts in power sockets are less reliable. If you find ground, and if you have a multimeter, you can measure voltages between ground, neutral and line.

A "dumb" heater doesn't care about voltage. Cool it enough and they will be fine regardless of voltage.
Still, it does not "fix" the issue though. He will still have to check when voltage get's up, hook up heater, check voltage again, connect other stuff if it goes low enough alternatively connect more heaters (?) if it doesn't, and then disconnect whatever heaters he connected when voltage spike is over and things get back to normal (otherwise he get's too low voltage for stuff to work, not to mentioned electric bill).
It's WAY too much gymnastics to make it work long term.
Just for diagnostics, not regulation.
 
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